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Road network comparisons - how to extract roads that do not completely fall within the buffer

Road network comparisons - how to extract roads that do not completely fall within the buffer


I am trying to compare how well one road network aligns with another - I have created a buffer around the first network and would like to select only the roads from the second network that fall COMPLETELY within that buffer, OR only have small extensions that go beyond.

I have done both a clip and erase of the second network by the buffer and joined those sets to find the set that fall both within and outside the buffer to remove them, but need to find a way to not remove those that "mostly match"

i.e. how can I remove the roads that do not match the buffer but are included because part of the road is within the buffer, as in a T intersection, without also removing those roads that have smaller parts not falling within the buffer?

It doesn't have to be a 100% solution, there is room for a reasonable amount of error


Look into Multipart To Singlepart (Data Management) it will break up the roads into single parts, which should make your selection more accurate.


Image feature based GPS trace filtering for road network generation and road segmentation

We propose a new method to infer road networks from GPS trace data and accurately segment road regions in high-resolution aerial images. Unlike previous efforts that rely on GPS traces alone, we exploit image features to infer road networks from noisy trace data. The inferred road network is used to guide road segmentation. We show that the number of image segments spanned by the traces and the trace orientation validated with image features are important attributes for identifying GPS traces on road regions. Based on filtered traces , we construct road networks and integrate them with image features to segment road regions. Our experiments show that the proposed method produces more accurate road networks than the leading method that uses GPS traces alone, and also achieves high accuracy in segmenting road regions even with very noisy GPS data.

This is a preview of subscription content, access via your institution.


20 Answers 20

Mass transit and alternatives to cars

There are many countries that are focused on cars. As I'm from the Netherlands it's easy to think about grabbing a bike. Every person/group of persons on a bike for short distances (which can still be quite a lot of km, depending on the person) will be a car less.

The thing is that some countries, like the USA, can't imagine going without cars. An example is from a channel I watched called "notjustbikes" on youtube. It stated that small shops inside urban areas is for them unimaginable. Their lives revolve around big one time pickups at huge shops, all by car. In contrast there are many counties where you can walk to a shop for daily groceries, removing most of the shopping by car. This is but one example, but a lot of reduction of traffic can be gained by a different mindset in planning and the populace. Having most commodities like work, shopping and relaxation easily reachable by foot or bike will reduce the cars by a huge margin.

We're not there yet. Cars have been planted in many brains as a flexible and easy transport that can get you anywhere. In the USA you take a plane or a car to another state. Why? Because a long bus ride is horrible, trains are barely existent and there are no other alternatives. However, if you invest more into other transport like busses, trains or other instead of cars, they become more viable. Multiple people in a vehicle reduces the amount of vehicles on the road. Not all vehicles even need a paved road. Would you take the car if you can't park and there is a cheap, fast and easy train connection? Would you take the car if you're only allowed 50 maximum on not well maintained roads while beautiful well maintained mass transit is available?

It is again partly a mind problem, but the message is simple. If there are better, faster and cheaper alternatives to cars, they will use them. Removing most if not all cars will allow you to reduce the road network. Simple as that. In addition, many mass transit examples can use electricity, which can be created with nuclear, tidle, wind, solar and other green alternatives to fossil fuel. You can immediately change from gas to hydrogen, which can be put into cars as a consumable fuel and be produced from (excess) electricity. This can be both burned (for example to cook) and used to directly make electricity in special cells.

I'm thinking that we can't reduce it to 10% of the original. You still need some trucks to deliver things at the shops and such. But there we see the problem! My mindset can't think without trucks for the shops. But a full change in this mindset can solve this. Maybe there are solutions where it is passed on automated rails underground to each shop from a railway distribution center. Maybe you use a fleet of cargo bikes from a smaller distribution center instead! There are options, but we need a new extensive infrastructure and mindset to make it happen. There are multiple combinations of options for this, so no single answer.

There is also some bonus points for growing locally. Using a mandated amount of roof space for growing food can already make a huge impact. Furthermore you can have more green where you grow these things. If people get a mindset where things like permaculture (round the year mixed food production. Work itensive but little land produces more) are commonplace, you can reach such targets quite quickly.


Abstract

For future energy planning and sustainable development, the share of renewable energy in the national power production must be increased. For this reason, energy managers and deciders would impose models and strategies for future renewable energy planning development. The site selection of new renewable energy projects constitutes a huge challenge, due to the contributions of several factors in the decision-making process. This study has two main objectives, the first is to develop an alternative framework for site selection of large-scale parabolic trough concentrating solar power on-grid plants as an essential future solar power in Algeria. A Geographic Information System (GIS) based analysis combined with Multi Criteria Decision Making techniques to develop a high-resolution map that identify and classify the suitable locations for setting up these projects. Several criteria are used in GIS analysis process, a map of direct normal solar irradiation and sunshine duration were developed with high resolution of (92×92 m/pixel) and grid power map was presented in its updatable form. The prioritization degree of the available siting zones is presented through three scenarios where distinct opinions of different energy related groups are considered by using different weighting methods EQual Weighted (EQW), Analytic Hierarchy Process(AHP) and Best Worst Method (BWM).

Second, the paper assesses the theoretical and technical potential of energy generation using concentrating solar power plants. A sensitivity analysis is applied for the suitable lands and finally, the results show that approximately 11% of the study area is considered as available lands for concentrating solar power energy generation with yearly electricity generation 34,453 TWh. The provinces of Bechar, Naama, Elbayadh, Laghouat, Gherdaïa, and Ouargla presenting the large lands of most suitable class (approximately 15,384.73 km 2 and 15,986.34 km 2 in AHP and BWM scenario respectively. Where the energy generation can reach more than 2,100 TWh/year, which can cover 38 time the national electricity demand.


A pre-requisite for sustainable management of natural resources is the availability of timely, cost-effective and comprehensive information of the condition and development trends of the specific resource. Remote sensing has always been an essential source of such information. Specifically, forestry has long benefited from these techniques: the literature on analytic algorithms for forest areas based on remotely sensing data is abundant. Nonetheless, the operational applicability of research results needs to be improved. Moreover, remote sensing researchers often seek purely academic objectives, lacking the support and quality guidance from practical forest management objectives. Thus, science-driven solutions for knowledge transfer between researchers and forest stakeholders/policy makers/end users are becoming increasingly important.

With this Special Issue, we aim at compiling research papers dealing both with remote sensing methodologies and the implementation of research results to facilitate sustainable forest management. The focus is placed on remotely sensed data, the development of algorithms for forest site characterization, wood characterization, biomass and CO2 stocking, mapping forest conditions, ecosystem vulnerabilities, socioeconomic functions and conditions, as well as on operationalization of remote sensing for natural resource management through the integration of scientific research and its practical utilisation. Overall, we call out for contributions combining remote sensing and any of the targets of the 2030 strategic research and innovation agenda for the forest based sector. Review contributions are also suitable for the Special Issue.

This special issue is linked with H2020 project MySustainableForest, however, contributions from other researchers are very welcome.

Prof. Dr. Gintautas Mozgeris
Dr. Ivan Balenović
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Remote Sensing is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.


Results

This section first shows the results of multicollinearity analysis and an information gain ratio (IGR) for the selection of forest fire influencing factors. The loss and the accuracy in the training/validation phases were tracked. Then, the test dataset was fed into the trained model and the prediction map of ignition probabilities was constructed by the CNN model. Finally, the performance of the proposed model was compared with benchmark methods.

Relative Importance Analysis of Influencing Factors

According to the results of a multicollinearity analysis of the 14 forest fire influencing factors in Table 4, three factors—precipitation rate, specific humidity, and maximum temperature—did not satisfy the critical values, suggesting the existence of multicollinearity and should be excluded from further analyses.

For the IGR method, the factors with a higher value of average merit (AM) indicate a stronger prediction ability of the model. However, factors with AM values equal to or less than 0 indicate a “null” contribution to the forest fire susceptibility model and should be excluded from further analysis (Bui, Tuan, et al. 2016). The results listed in Fig. 5 show that the AM values of all remaining 11 influencing factors are greater than 0, indicating that all these influencing factors contribute to the model and should be retained in the following prediction process. Temperature is the most important factor for forest fire susceptibility, with the highest AM value of (0.139). It is followed by wind speed (0.131), surface roughness (0.112), precipitation (0.107), and elevation (0.102).

Average merit (AM) of each forest fire influencing factor using the information gain ratio (IGR) method

Model Accuracy

The training process was divided into training and validation phases. The validation dataset was used to monitor the model classification performance after the end of each epoch, and the validation results were used as the basis for whether the training process should be terminated earlier or the hyperparameters should be fine-tuned. The loss and accuracy were two important indicators for evaluating the effect of model training. Callback functions were applied to adjust the training state and statistics during model training, including “EarlyStopping,” “ReduceLROnPlateau,” and “ModelCheckpoint.”

Figure 6 shows the loss and the training/validation accuracy using TensorBoard for visualization. After the training phase, the training accuracy was close to 91%, the training loss no longer decreased after the 100th epoch and tended to fit, and the minimum loss value was 0.3. After the 80th epoch, the validation loss no longer decreased and tended to converge. However, the validation loss rose slightly after the 120th epoch, suggesting overfitting may have occurred. Immediately, the EarlyStopping function ended the training process to decrease the phenomenon of overfitting. The validation accuracy of the model reached 82%, and the minimum validation loss was 0.45.

a, b Represent the training accuracy and the convergence graph of the training loss, respectively c, d represent the validation accuracy and the convergence graph of the validation loss, respectively

The slow decline curve of validation loss indicates that the model was well fitted. Overfitting did not occur because the training process was effectively terminated by the “EarlyStopping” function. After the training process, the model corresponding to the epoch with the lowest loss of the validating dataset in Check_pointer was selected as the final classification model.

Susceptibility Map

After the training process, a classification model was achieved. A test dataset—the VRD of 2010—was then used at the end of the project to evaluate the performance of the final model. The VRD of 2010 was fed into the classification model to predict forest fire susceptibility. The model resulted in probabilities for both the fire and nonfire classes on each pixel in the generated prediction map. Notably, although the CNN was designed to predict a single label from a small input patch of size 25 × 25 × 11, the CNN was trained to predict all pixels in the new VRD since the sliding window was densely overlapped and covered the entire VRD during the reasoning phase. The sum of the probabilities of the fire and nonfire class was 1 on each pixel. The probability of the fire class was chosen as the final predicted probability value, and then we produced a map of the probability values for all pixels by converting the array data into an image using the libtiff package in Python. The forest fire susceptibility map was finally produced by dividing the image into five levels using the natural breaks method in ArcGIS10.5. Five susceptible classes were identified—very low, low, moderate, high, and very high—for constructing the forest fire susceptibility map (Fig. 7).

Forest fire susceptibility map derived from the convolutional neural network (CNN) model for Yunnan Province, China, in 2010

From the predicted susceptibility results, we can see that the highest forest fire ignition susceptibilities are mainly distributed in the south and northwest of Yunnan Province. The areas with the lowest forest fire ignition susceptibilities are in the central and northeastern parts of Yunnan.

Model Comparison

The usability of the proposed model was compared with benchmark methods random forests (RF), support vector machine (SVM), multilayer perceptron neural network (MLP), and kernel logistic regression (KLR). The four benchmark methods were built and implemented using the scikit-learn package, and the grid search method was used to optimize the hyperparameters. The main hyperparameters utilized in the benchmark methods are listed in Table 5. Recursive feature elimination with cross-validation was employed to perform automatic tuning of the number of features selected for SVM and KLR.

The performance of the five models was evaluated and compared for both the training and validation datasets of 2009. Table 6 shows that the CNN had the higher specificity (93.77%), sensitivity (97.84%), PPV (94.02%), NPV (97.75%), and overall accuracy (95.81%) for the training dataset than the four benchmark methods. The proposed CNN model had the highest overall accuracy (87.92%) for the validation dataset, followed by the RF (84.36%), KLR (81.23%), SVM (80.04%), and MLP (78.47%).

Figure 8 illustrates the ignition susceptibility map constructed by the benchmark models using the same test datasets. The values denote the probabilities of each pixel having an ignition occurrence. To enhance the comparability of the prediction results for the CNN and benchmark models, the probability map was divided into five classes with the same natural breaks method as CNN. It can be observed that in the prediction maps of SVM, MLP, and KLR, forest fire susceptibility of most areas in the northwest of Yunnan Province was categorized as very low and low. In contrast, CNN and RF can well-identify the ignition probabilities in the northwest. For the southern region of Yunnan Province, compared with the predicted results of the CNN model, the RF model divided most regions of southern Yunnan into very high susceptible zones, while the results of the SVM, MLP, and KLR models predicted high susceptibility only in the southwest region of Yunnan Province. The high fire occurrence region in the southeast was not clearly identified in the predicted results.

Prediction maps of the ignition probabilities for the benchmark models for Yunnan Province, China. KLR kernel logistic regression MLP multilayer perceptron neural network RF random forests SVM support vector machine

Figure 9 shows that the very high and very low susceptibility classes in the CNN model account for 77.51% of the total area, which was the highest proportion among all the models whereas the remaining three classes of high, moderate, and low have the lowest proportion of all models, accounting for 7.15%, 6.33%, and 9.01% of the total area, respectively. The results show that the proposed CNN model can effectively divide the very high and very low susceptible zones. However, the probability prediction results of the benchmark models had many areas within medium and high susceptibility zones, and there was no clear determination regarding zones with high forest fire susceptibility thus, what threshold segmentation method should be used to divide the fire warning areas needs to be considered. Most traditional ML methods will face this problem after obtaining the probability prediction results. In contrast, the probability results obtained by the CNN are more distinct in their spatial pattern, and the statistical values reflect a high and low bipolar distribution, which is more advantageous in the division of the areas with fire warnings and those without fire warnings and can reduce the influence of the threshold segmentation of the delineation of fire warning areas. Thus, the result of the CNN model is better for forest fire predictions.

Percentages of different forest fire susceptibility classes. CNN convolutional neural network RF random forests SVM support vector machine MLP multilayer perceptron neural network KLR kernel logistic regression

To confirm the statistical significance of the prediction performance between the proposed CNN model and the benchmark models, the nonparametric WSRT (Wilcoxon 1945) was employed for paired comparisons. The null-hypothesis (H0) was that there was no significant difference at 95% confidence intervals of two prediction models. If the p value was less than the significance level (0.05), H0 was rejected, and a significant difference exists in the models (Tien Bui et al. 2019). The analysis was performed using SPSS (Statistical Package for the Social Sciences), and the Wilcoxon signed-rank test (WSRT) results are reported in Table 7. The p value of all pairwise comparisons was less than 0.05, confirming that the classification performances of the proposed model and benchmark models are significantly different.

The ROC curves for the five models are depicted in Fig. 10. They were drawn using the 2010 prediction maps of the ignition probabilities and the corresponding IRD. The AUC provides a single measure of a classifier’s performance to evaluate which model is better on average. The AUC of the CNN model is 0.86 (Fig. 10), indicating that the global fit of the model with the testing dataset is 86%, followed by RF (0.82), SVM (0.79), MLP (0.78), and KLR (0.78). The ROC curves clearly show that the CNN model has the highest prediction performance.

Receiver operating characteristic (ROC) curves and area under the curve (AUCs) of the five models. CNN convolutional neural network RF random forests SVM support vector machine MLP multilayer perceptron neural network KLR kernel logistic regression


Results

Figure 2 compares the critical points of all 107 networks with sample statistics (overline<

^>=12236pm 5513) vehicle-km h −1 km −2 (mean ± standard deviation) and (overline<^>=653pm 308) vehicles km −2 (mean ± standard deviation). Figure 2a shows the intuitive positive relationship between critical accumulation and network capacity with R 2 = 0.91. R 2 < 1 implies – ignoring measurement uncertainties - that other factors create variation in critical points as well. This variation is also emphasized by the kernel density estimate of the critical speed in Fig. 2b, revealing a substantial variation of critical points across regions. This implies that in some regions, car drivers can experience low speeds, but against intuition, the network is not macroscopically congested. The distribution of critical accumulation in our sample is consistent with the traffic physics literature 19 that predicts that critical accumulation does not exceed one third of the jam accumulation.

Comparison of urban traffic capacity across 107 urban networks. (a) Positive relationship of network capacity against critical accumulation (R 2 = 0.92). (b) Kernel density estimate of critical speeds of all networks emphasizes that congestion starts at different speeds in different networks (mean 18.8 km/h).

To quantify the critical point relationship in Fig. 2a and the influence of bus and road network topology on the critical point, we use a two-stage least squares regression analysis because the influence of critical accumulation on capacity is endogenous and requires instrumental variables. We focus on exogenous variables linked to the full network properties of bus and road network topology that are not only macroscopic, but also measurable from OpenStreetMap, common to all cities, and clearly interpretable. We do not consider city-specific factors, e.g. bicycle policies, although they undoubtedly also influence the critical point. On a broader level, the exogenous variables should describe conflicts between vehicles that cause delays. For example, delays appear when two vehicles want to be at the same time at the same place (i.e. at intersections), or when cars must follow buses or cyclists. All these conflicts influence the total travel time of drivers or even the travelled distance of vehicles, both of which affect the location of the critical point. Accordingly, we define four variables. First, road network density R (lane-km km −2 ) with sample statistics (ar=23.46pm 10.36) lane-km km −2 (mean ± standard deviation). Second, network redundancy, measured in the network average betweenness centrality bc (−) with sample statistics (overline<_>=0.084pm 0.039) (mean ± standard deviation). Third, the average distance between or spacing of signalized intersections (LSA) in the network I (LSA network-km −1 ) with sample statistics (ar=0.385pm 0.188) LSA network-km −1 (mean ± standard deviation). Fourth, the bus production density B (bus-km h −1 km −2 ) that combines the density of the bus network per unit area with the average headway with sample statistics (ar=147pm 85.5) bus-km h −1 km −2 (mean ± standard deviation). We expect that R, bc and I affect the critical accumulation (via total travel time) and B affects capacity (via total travelled distance). Consequently, the first three variables correspond to the required instruments for the critical accumulation. In particular, we expect that n * increases with R as more road space per unit area generally allows more vehicles to circulate, but denser networks provide more opportunities for conflicts (at intersections, through lane changes, etc.), resulting in a sublinear scaling 8,20,21 between R and n * . In low redundancy networks with few alternative routes, the concentration of vehicles on these routes reduces the critical accumulation compared to networks with many alternative routes 22,23,24 , i.e. n * decreases with bc. In a network of density R, we expect that a denser intersection spacing increases travel times due to more waiting compared to a network of the same density R with a larger intersection spacing 5,6,15,25 , consequently we expect that the interaction of I and R has a negative effect on P * . Last, buses are usually larger than cars and can behave as either stationary bottlenecks at bus stops, or as moving bottlenecks when driving, consequently, P * should decrease with B 26,27,28,29,30 .

Table 1 summarizes the model estimates. Tables 2–4 in the Supplementary information provide alternative model specification to check the robustness of the critical point model that are formulated without observation weights, in log-specification and in a critical density (not accumulation). While the first two robustness model specifications test the influence of observation weights and functional form, we rule out with the latter the possibility of a bias caused by scaling density to accumulation. We have to reject the hypothesis that critical accumulation is exogenous, consequently, the two stage least squares is required. We find that we can significantly explain around 90% of the observed critical point variation with just four exogenous variables describing bus and road network topology. We cannot explain the entire variation because we do not include city-specific factors, nor those that are not clearly measurable. Further, we see that the elasticity of n * is not statistically significantly different from one, meaning that efforts to increase the critical accumulation affect capacity proportionally. Contrary, we find that the elasticity of R on the critical accumulation is significantly different from one, with ε ≈ 0.8. All robustness models in the Supplementary information confirm this result.

In Fig. 3, we illustrate the effects underlying the results from Table 1 graphically to show how the variation in the data drives the critical point variation. We conclude that even with the rather small empirical variation in bus and road network topology across cities, there is substantial variation in the critical point. Figure 4 provides a sensitivity analysis of the presented relationships for a likely occurrence of n * becoming an interval (i.e. multiple maxima) instead of a single point 10 . This behavior can occur due to the complexity of urban traffic and for uncertainty in the critical density estimation. This sensitivity analysis shows that the identified relationships are robust against the occurrence of n * becoming an interval.

Illustration of the effects in the critical point model. (a) Influence of road network density on critical accumulation. (b) Influence of betweenness centrality (network redundancy) on critical accumulation. (c) Influence of intersection density on critical accumulation. (d) Capacity reduction by bus operations in the network. Panels (a–c) are constructed as follows. We first residualize the x- and y-variables on the other control variables of the critical point model as given in Table 1. Secondly, we add back the unconditional mean of the x- and y-variables to the residuals. Panel (d) is constructed by calculating each network’s capacity at zero bus production and then calculating the relative difference to the observed capacity. The solid black line in each panel corresponds to the linear fit of the scatterplots.

Robustness check for the situation if the critical accumulation becomes an interval. The points in each panel correspond to the estimated maximum of each MFD, while the horizontal or vertical bars describe the interval in accumulation that results from a 5% reduction of the capacity. (a) Scatterplot capacity versus accumulation. (b) Influence of road network density. (c) Influence of betweenness centrality. (d) Influence of intersection density.

We emphasize in Fig. 5 the effects of changes in bus and road network topology on the critical point and the MFD. In other words, the results in Fig. 5 illustrate macroscopic trade-offs for urban transportation policies. We choose a simple bi-quadratic function 31 for the MFD to clearly mark the critical point location. In particular, we show in Fig. 5a the influence of road network density, in Fig. 5b the influence of network redundancy, in Fig. 5c the influence of intersection spacing, and in Fig. 5d the influence of bus headways. Clearly, Fig. 5a shows that more roads in the network increase the total production of the network, but the elasticity of road network density from Table 1 points towards the important policy implication of decreasing marginal returns of road network expansion. Figure 5b,c describe the macroscopic trade-off between vehicular and non-vehicular traffic and walkability of a city. More intersections provide more right of way to pedestrians and a concentration of vehicular traffic on few routes could mean less negative car externalities for non-vehicular modes elsewhere in the network. Figure 5d emphasizes a universal trade-off between buses and cars allowing cities to optimize passenger throughput under further assumptions on vehicle occupancy levels and bus services. The results from Table 1 and the illustrations in Fig. 5 imply that cities can now understand how investment measures benefit or harm the capacity of entire networks. Importantly, these measures go beyond just building roads.

Illustration of the effects in the critical point model. (a) Influence of road network density on critical accumulation. (b) Influence of betweenness centrality (network redundancy) on critical accumulation. (c) Influence of intersection density on critical accumulation. (d) Capacity reduction by bus operations in the network. The MFDs are constructed as follows. We use the model estimates from Table 1 to predict the critical point. We use the following values for the variables that remain fixed in each graph: R = 50 lane-km km −2 , bc = −2, I = 0.2 LSA km −1 , LBN = 50 line-network-km km −2 , HW = 8/60 h.


V. Preparation of NHL Nominations


A thorough knowledge of the property and the national context in which it is to be evaluated are the beginning points for completing a nomination. The following information should be provided in order to illustrate how a property possesses exceptional value or quality in illustrating or interpreting a national context and to make a compelling justification for NHL designation.

Cite and justify the qualifying NHL criteria,

State the related NHL theme (see Chapter III on NHL Theme Studies) and explain the property's relationship to it,

Explain how the property has significance at a national level (which must include a summary statement of national significance to introduce the significance section),

Outline the historical background of this individual property, and

Establish the relative merit of the significance and integrity of the property in comparison to other similar, potentially nominated properties.

Nomination preparers should use the NHL form which is a slightly modified National Register of Historic Places Registration Form (NPS Form 10-900) to nominate properties for designation. A computer template for this form is available on diskette from the National Historic Landmarks Survey and NPS regional and support offices that work with the NHL Program along with technical instructions for its completion. When submitting a nomination, the electronic version of the nomination should be submitted, whether on diskette or via electronic mail, along with a printed copy of the nomination.

Anyone wishing to prepare an NHL nomination should first consult either the NHL Survey or the NPS regional and support office staff for information about theme studies and other comparable properties that may be relevant in the evaluation of particular properties and for preliminary advice on whether a property appears likely to meet NHL criteria. Copies of relevant studies and National Register documentation should be consulted if the property is listed in the National Register. State Historic Preservation Officers, Federal Preservation Officers, and Tribal Preservation Officers should also be consulted for information in their inventories that may be helpful in documenting a property.

The following special instructions for the text should be followed:

NHL Form Section 1. Name of Property

Historic Name


Select the historic name reflecting the property's national significance.

Bethune, Mary McLeod, Home
Princeton Battlefield
Virginia City Historic District

Other Names/Site Number


Enter any other names by which the property has been commonly known. These names may reflect the property's history, current ownership, or popular use and may or may not reflect the historic name. Site numbers are often assigned to archeological sites for identification. This number may be placed on this line.

NHL Form Section 2. Location


Enter the street address of the property or the most specific location when no street number exists.
Mark an "x" in the boxes for both "not for publication" and "vicinity" (and add the name of the nearest city or town in the provided blank) to indicate that a property needs certain protection. The NPS shall withhold from disclosure to the public information about the location, character, or ownership of a historic resource if the Secretary of the Interior and the NPS determine that disclosure may

cause a significant invasion of privacy,

risk harm to the historic resource, or

impede the use of a traditional religious site by practitioners.

The Federal Register will indicate "Address Restricted" and give the nearest city or town as the property=s location. The NHL database will also refer to the location this way. Further, the NPS will exclude location and other appropriate information from any copies of documentation requested by the public.

Any information about the location, boundaries, or character of a property that should be restricted should be compiled on a separate sheet. On the same sheet, explain the reasons for restricting the information.

When it has been determined that this information should be withheld from the public, the Secretary, in consultation with the official recommending the restriction of information, shall determine who may have access to the information for the purpose of carrying out the National Historic Preservation Act.

NHL Form Section 3. Classification

Ownership of Property

Mark an "x" in all boxes that apply to indicate ownership of the property.

Category of Property


Mark an "x" in only one box to indicate the type of property being documented.

Name of Multiple Property Listing


Enter the name of the multiple property listing if the property is being nominated as part of a multiple property submission.

Number of Resources Within Property


Enter the number of resources in each category that make up the property. Count contributing resources separately from noncontributing resources. Total each column.

A contributing building, site, structure, or object adds to the historical associations, historic architectural qualities, or archeological values for which a property is nationally significant because it was present during the period of significance, relates to the documented significance of the property, and possesses a high degree of historical integrity.

A noncontributing building, site, structure, or object was not present during the period of national significance, does not relate to the documented national significance of the property, or due to alterations, disturbances, additions, or other changes, it no longer possesses a high degree of historical integrity. If resources of state or local significance are included and their significance is justified in the documentation, they should be counted separately from those that contribute to the national significance.

Number of Contributing Resources Previously Listed in the National Register


Enter the number of any contributing resources already listed in the National Register. This would include both previously designated NHLs and authorized historic units of the National Park System as well as other previously listed National Register properties. If no resources are already listed, enter "N/A."

National Register Property and Resource Types

Building - A building, such as a house, barn, church, hotel, or similar construction, is created principally to shelter any form of human activity. "Building" may also be used to refer to a historically and functionally related unit, such as a courthouse and jail or a house and barn.

Examples: houses, barns, stables, sheds, garages, courthouses, city halls, social halls, commercial buildings, libraries, factories, mills, train depots, stationary mobile homes, hotels, theaters, schools, stores, and churches.

Site - A site is the location of a significant event, a prehistoric or historic occupation or activity, or a building or structure, whether standing, ruined, or vanished, where the location itself possesses historic, cultural, or archeological value regardless of the value of any existing structure.

Examples: habitation sites, funerary sites, rock shelters, village sites, hunting and fishing sites, ceremonial sites, petroglyphs, rock carvings, gardens, grounds, battlefields, ruins of historic buildings and structures, campsites, sites of treaty signings, trails, areas of land, shipwrecks, cemeteries, designed landscapes, and natural features, such as springs and rock formations, and land areas having cultural significance.

Structure - The term "structure" is used to distinguish from buildings those functional constructions made usually for purposes other than creating human shelter.

Examples: bridges, tunnels, gold dredges, firetowers, canals, turbines, dams, power plants, corncribs, silos, roadways, shot towers, windmills, grain elevators, kilns, mounds, cairns, palisade fortifications, earthworks, railroad grades, systems of roadways and paths, boats and ships, railroad locomotives and cars, telescopes, carousels, bandstands, gazebos, and aircraft.

Object - The term "object" is used to distinguish from buildings and structures those constructions that are primarily artistic in nature or are relatively small in scale and simply constructed. Although it may be, by nature or design, movable, an object is associated with a specific setting or environment.

Examples: sculpture, monuments, boundary markers, statuary, and fountains.

District - A district possesses a significant concentration, linkage, or continuity of sites, buildings, structures, or objects united historically or aesthetically by plan or physical development.

Examples: college campuses central business districts residential areas commercial areas large forts industrial complexes civic centers rural villages canal systems collections of habitation and limited activity sites irrigation systems large farms, ranches, estates, or plantations transportation networks and large landscaped parks.

Rules for Counting Resources

Count all buildings, structures, sites, and objects located within the property's boundaries that are substantial in size and scale. Do not count minor resources, such as small sheds or grave markers, unless they strongly contribute to the property's historic significance.

Count a building or structure with attached ancillary structures, covered walkways, and additions as a single unit unless the attachment was originally constructed as a separate building or structure and later connected.

Count rowhouses individually, even though attached.

Do not count interiors, facades, or artwork separately from the building or structure of which they are a part.

Count gardens, parks, vacant lots, or open spaces as "sites" only if they contribute to the significance of the property.

Count a continuous site as a single unit regardless of its size or complexity.

Count separate areas of a discontiguous archeological district as separate sites.

Do not count ruins separately from the site of which they are a part.

Do not count landscape features, such as fences and paths, separately from the site of which they are a part unless they are particularly important or large in size and scale, such as a statue by a well-known sculptor or an extensive system of irrigation ditches.

If a group of resources, such as backyard sheds in a residential district, was not identified during a site inspection and cannot be included in the count, state that this is the case and explain why in the narrative for section 7.

For additional guidance, contact the SHPO.

Guidelines for Entering Functions

Enter the most specific category and subcategory. For example, "Education/education-related housing" rather than "Domestic/institutional housing" for a college dormitory.

If no subcategory applies, enter the general category by itself. If, in addition, none of the general categories relates to the property's function, enter "Other:" and an appropriate term for the function.

For properties with many functions, such as a farm, list only the principal or predominant ones, placing the most important first.

For districts, enter the functions applying to the district as a whole, such as Domestic/village site or Education/college.

For districts, also enter the functions of buildings, sites, structures, and objects that are:

of outstanding importance to the district, such as a county courthouse in a commercial center (Government/county courthouse) or,

present in substantial numbers, such as apartment buildings in a residential district (Domestic/multiple dwelling) or storage pits in a village site (Trade/trade).

For districts containing resources having different functions and relatively equal importance, such as a group of public buildings whose functions are Government/city hall, Government/courthouse, and Government/post office.


Historic Functions

Enter functions for contributing resources only.

Select functions that relate directly to the property's significance and occurred during the period of significance (see Period of Significance).

Enter functions for extant resources only.

Enter only functions that can be verified by research, testing, or examination of physical evidence.

Enter functions related to the property itself, not to the occupation of associated persons or role of associated events. For example, the home of a prominent doctor is "Domestic/single dwelling" not "Health Care/medical office" unless the office was at home (in which case, list both functions).


Current Functions

Enter functions for both contributing and noncontributing resources.

For properties undergoing rehabilitation, restoration, or adaptive reuse, enter "Work in Progress" in addition to any functions that are current or anticipated upon completion of the work.

NHL Form Section 4. State/Federal Agency Certification


Preparers should leave this blank.

NHL Form Section 5. National Park Service Certification


Preparers should leave this blank.

NHL Form Section 6. Function or Use

Historic Function


Select one or more category and subcategory that most accurately describe the property's principal historic functions. Enter functions for contributing resources only and for extant resources only. Select functions that relate directly to the property's significance and occurred during the period of national significance. Enter only functions that can be verified by research, testing, or examination of physical evidence.

Current Function


Select one or more category and subcategory that most accurately describe the property's most recent principal functions. Enter functions for both contributing and noncontributing resources.

Data Categories for Functions and Uses:

Category: Domestic

  • Subcategory:
    1. single dwelling
      • Examples: single dwelling rowhouse, mansion, residence, rockshelter, homestead, cave
      • Examples: duplex, apartment building, pueblo, rockshelter, cave
      • Examples: dairy, smokehouse, storage pit, storage shed, kitchen, garage, other dependencies
      • Examples: inn, hotel, motel, way station
      • Examples: military quarters, staff housing, poor house, orphanage
      • Examples: hunting campsite, fishing camp, summer camp, forestry camp, seasonal residence, temporary habitation site, tipi rings
      • Examples: pueblo group

      Category: Commerce/Trade

      • Subcategory:
        1. business
          • Examples: office building
          • Examples: architect's studio, engineering office, law office
          • Examples: trade union, labor union, professional association
          • Examples: savings and loan association, bank, stock exchange
          • Examples: auto showroom, bakery, clothing store, blacksmith shop, hardware store
          • Examples: general store, department store, marketplace, trading post
          • Examples: cafe, bar, roadhouse, tavern
          • Examples: warehouse, commercial storage
          • Examples: cache, site with evidence of trade, storage pit

          Category: Social

          • Subcategory:
            1. meeting hall
              • Examples: grange union hall Pioneer hall hall of other fraternal, patriotic, or political organization
              • Examples: facility of literary, social, or garden club
              • Examples: facility of volunteer or public service organizations such as the American Red Cross

              Category: Government

              • Subcategory:
                1. capitol
                  • Examples: statehouse, assembly building
                  • Examples: city hall, town hall
                  • Examples: police station, jail, prison
                  • Examples: firehouse
                  • Examples: municipal building
                  • Examples: embassy, consulate
                  • Examples: custom house
                  • Examples: post office
                  • Examples: electric generating plant, sewer system
                  • Examples: county courthouse, federal courthouse

                  Category: Education

                  • Subcategory:
                    1. school
                      • Examples: schoolhouse, academy, secondary school, grammar school, trade or technical school
                      • Examples: university, college, junior college
                      • Examples: library
                      • Examples: laboratory, observatory, planetarium
                      • Examples: college dormitory, housing at boarding schools

                      Category: Religion

                      • Subcategory:
                        1. religious facility
                          • Examples: church, temple, synagogue, cathedral, mission, temple, mound, sweathouse, kiva, dance court, shrine
                          • Examples: astronomical observation post, intaglio, petroglyph site
                          • Examples: religious academy or schools
                          • Examples: parsonage, convent, rectory

                          Category: Funerary

                          • Subcategory:
                            1. cemetery
                              • Examples: burying ground, burial site, cemetery, ossuary
                              • Examples: burial cache, burial mound, grave area, crematorium
                              • Examples: mortuary site, funeral home, cremation

                              Category: Recreation and Culture

                              • Subcategory:
                                1. theater
                                  • Examples: cinema, movie theater, playhouse
                                  • Examples: hall, auditorium
                                  • Examples: museum, art gallery, exhibition hall
                                  • Examples: concert-hall, opera house, bandstand, dance hall
                                  • Examples: gymnasium, swimming pool, tennis court, playing field, stadium
                                  • Examples: park, campground, picnic area, hiking trail,fair, amusement park, county fairground
                                  • Examples: commemorative marker, commemorative monument
                                  • Examples: sculpture, carving, statue, mural, rock art

                                  Category: Agriculture/Subsistence

                                  • Subcategory:
                                    1. processing
                                      • Examples: meatpacking plant, cannery, smokehouse, brewery, winery, food processing site, gathering site, tobacco barn
                                      • Examples: granary, silo, wine cellar, storage site, tobacco warehouse, cotton warehouse
                                      • Examples: pasture, vineyard, orchard, wheatfield, crop field marks, stone alignments, terrace, hedgerow
                                      • Examples: hunting & kill site, stockyard, barn, chicken coop, hunting corral, hunting run, apiary
                                      • Examples: fish hatchery, fishing grounds
                                      • Examples: greenhouse, plant observatory, garden
                                      • Examples: wellhouse, wagon shed, tool shed, barn
                                      • Examples: irrigation system, canals, stone alignments, headgates, check dams

                                      Category: Industry/Processing/Extraction

                                      • Subcategory:
                                        1. manufacturing facility
                                          • Examples: mill, factory, refinery, processing plant, pottery, kiln
                                          • Examples: coal mine, oil derrick, gold dredge, quarry, salt mine
                                          • Examples: reservoir, water tower, canal, dam
                                          • Examples: windmill, power plant, hydroelectric dam
                                          • Examples: telegraph cable station, printing plant, television station, telephone company facility, satellite tracking station
                                          • Examples: shell processing site, toolmaking site, copper mining and processing site
                                          • Examples: warehouse

                                          Category: Health Care

                                          • Subcategory:
                                            1. hospital
                                              • Examples: veteran's medical center, mental hospital, private or public hospital, medical research facility
                                              • Examples: dispensary, doctor's office
                                              • Examples: nursing home, rest home, sanitarium
                                              • Examples: pharmacy, medical supply store, doctor or dentist's office
                                              • baths, spas, resort facility

                                              Category: Defense

                                              • Subcategory:
                                                1. arms storage
                                                  • Examples: magazine, armory
                                                  • Examples: fortified military or naval post, earth fortified village, palisaded village, fortified knoll or mountain top, battery, bunker
                                                  • Examples: military post, supply depot, garrison fort, barrack, military camp
                                                  • Examples: battlefield
                                                  • Examples: lighthouse, coast guard station, pier, dock, lifesaving station
                                                  • Examples: submarine, aircraft carrier, battleship, naval base
                                                  • Examples: aircraft, air base, missile launching site

                                                  Category: Landscape

                                                  • Subcategory:
                                                    1. parking lot
                                                    2. park
                                                      • Examples: city park, state park, national park
                                                      • Examples: square, green, plaza, public common
                                                      • Examples: meadow, swamp, desert
                                                      • Examples: underwater site
                                                      • Examples: mountain, valley, promontory, tree, river, island, pond, lake
                                                      • Examples: street light, fence, wall, shelter, gazebo, park bench
                                                      • Examples: wildlife refuge, ecological habitat

                                                      Category: Transportation

                                                      • Subcategory:
                                                        1. rail-related
                                                          • Examples: railroad, train depot, locomotive, streetcar line, railroad bridge
                                                          • Examples: aircraft, airplane hangar, airport, launching site
                                                          • Examples: lighthouse, navigational aid, canal, boat, ship, wharf, shipwreck
                                                          • Examples: parkway, highway, bridge, toll gate, parking garage
                                                          • Examples: boardwalk, walkway, trail

                                                          Category: Work in Progress

                                                          NHL Form Section 7. Description

                                                          Architectural Classification


                                                          Complete this item for properties having architectural or historical importance. Select one or more subcategories to describe the property's architectural styles or stylistic influences. (See Figure 7.) If none of the subcategories describes the property's style or stylistic influence, enter the category relating to the general period of time. For properties not described by any of the listed terms, including bridges, ships, locomotives and buildings and structures that are prehistoric, folk, or vernacular in character, enter "other" with the descriptive term most commonly used to classify the property by type, period, method of construction, or other characteristics.

                                                          Other: Pratt through truss
                                                          Other: split-log cabin
                                                          Other: Gloucester fishing schooner.

                                                          Do not enter "vernacular" because the term does not describe any specific characteristics. For properties not having any buildings or structures enter N/A. For buildings and structures not described by the listed terms or by "other" and a common term, enter "No style."

                                                          Data Categories for Architectural Classification

                                                          Category: No Style

                                                          Category: Colonial

                                                          • Subcategory:
                                                            1. French Colonial
                                                            2. Spanish Colonial
                                                              • Other Stylistic Terminology: Mexican Baroque
                                                              • Other Stylistic Terminology: Flemish Colonial
                                                              • Other Stylistic Terminology: English, English Gothic Elizabethan Tudor Jacobean or Jacobethan New England Colonial Southern Colonial

                                                              Category: Early Republic

                                                              • Subcategory:
                                                                1. Early Classical Revival
                                                                  • Other Stylistic Terminology: Jeffersonian Classicism Roman Republican Roman Revival Roman Villa Monumental Classicism Regency
                                                                  • Other Stylistic Terminology: Adams or Adamesque

                                                                  Category: Mid-19th Century

                                                                  • Other Stylistic Terminology: Early Romanesque Revival
                                                                  • Subcategory:
                                                                    1. Greek Revival
                                                                      • Other Stylistic Terminology: Early Gothic Revival
                                                                      • Other Stylistic Terminology: Egyptian Revival Moorish Revival

                                                                      Category: Late Victorian

                                                                      • Other Stylistic Terminology: Victorian or High Victorian Eclectic
                                                                      • Subcategory:
                                                                        1. Gothic
                                                                          • Other Stylistic Terminology: High Victorian Gothic Second Gothic Revival
                                                                          • Other Stylistic Terminology: Victorian or High Victorian Italianate
                                                                          • Other Stylistic Terminology: Mansard
                                                                          • Other Stylistic Terminology: Queen Anne Revival Queen Anne-Eastlake
                                                                          • Other Stylistic Terminology: Eastern Stick High Victorian Eastlake
                                                                          • Other Stylistic Terminology: Romanesque Revival Richardsonian Romanesque
                                                                          • Other Stylistic Terminology: Renaissance Revival Romano-Tuscan Mode North Italian or Italian Renaissance French Renaissance Second Renaissance Revival

                                                                          Category: Late 19th & 20th Century Revivals

                                                                          • Subcategory:
                                                                            1. Beaux Arts
                                                                              • Other Stylistic Terminology: Beaux Arts Classicism
                                                                              • Other Stylistic Terminology: Georgian Revival
                                                                              • Other Stylistic Terminology: Neo-Classical Revival
                                                                              • Other Stylistic Terminology: Jacobean or Jacobethan Revival Elizabethan Revival
                                                                              • Other Stylistic Terminology: Collegiate Gothic
                                                                              • Other Stylistic Terminology: Spanish Revival Mediterranean Revival

                                                                              Category: Late 19th & Early 20th Century American Movements

                                                                              • Other Stylistic Terminology: Sullivanesque
                                                                              • Subcategory:
                                                                                1. Prairie School
                                                                                2. Commercial Style
                                                                                3. Chicago
                                                                                4. Skyscraper
                                                                                5. Bungalow/Craftsman
                                                                                  • Other Stylistic Terminology: Western Stick Bungaloid

                                                                                  Category: Modern Movement

                                                                                  • Subcategory:
                                                                                    1. Modern Movement
                                                                                      • Other Stylistic Terminology: New Formalism Neo-Expressionism Brutalism California Style or Ranch Style Post-Modern Wrightian
                                                                                      • Other Stylistic Terminology: Modernistic Streamlined Moderne Art Moderne
                                                                                      • Other Stylistic Terminology: Miesian

                                                                                      Category: Other

                                                                                      Category: Mixed

                                                                                      Materials


                                                                                      Enter one or more terms to describe the principal exterior materials of the property. Enter only materials visible from the exterior of a building, structure, or object. Do not enter materials of interior, structural, or concealed architectural features even if they are significant. Enter both historic and nonhistoric materials. Under "other" list the principal materials of other parts of the exterior, such as chimneys, porches, lintels, cornices, and decorative elements. For historic districts, list the major building materials visible in the district, placing the most predominant ones first.

                                                                                      Data Categories for Materials

                                                                                      Category:

                                                                                      1. Earth
                                                                                      2. Wood
                                                                                        • Examples: Weatherboard Shingle Log Plywood/particle board Shake
                                                                                      3. Brick
                                                                                      4. Stone
                                                                                        • Examples: Granite Sandstone (including brownstone) Limestone Marble Slate
                                                                                      5. Metal
                                                                                        • Examples: Iron Copper Bronze Tin Aluminum Steel Lead Nickel Cast Iron
                                                                                      6. Stucco
                                                                                      7. Terra cotta
                                                                                      8. Asphalt
                                                                                      9. Concrete
                                                                                      10. Adobe
                                                                                      11. Ceramic Tile
                                                                                      12. Glass
                                                                                      13. Cloth/canvas
                                                                                      14. Synthetics
                                                                                        • Examples: Fiberglass Vinyl Rubber Plastic
                                                                                      15. Other

                                                                                      Narrative Description


                                                                                      Provide a narrative describing the property and its physical characteristics. Describe the setting, buildings, and other major resources, outbuildings, surface and subsurface remains (for properties with archeological national significance), and landscape features for all contributing and noncontributing resources. The narrative must document the evolution of the property, describing major changes since its construction or period of national significance.

                                                                                      This section should begin with a summary paragraph that briefly describes the general characteristics of the property, such as its location and setting, type, style, method of construction, size, and significant features. The summary paragraph should create a rough sketch of the property and its site and then use subsequent paragraphs to fill in the details.

                                                                                      The rest of the narrative should describe the current condition of the property and indicate whether the property has historic integrity in terms of location, design, setting, materials, workmanship, feeling, and association. Clearly delineate between the original appearance and current appearance. The more extensively a property has been altered, the more thorough the description of additions, replacement materials, and other alterations should be. Photographs and sketch maps must be used to supplement the narrative. (See Additional Documentation Section for more information.)

                                                                                      The description should be concise, factual, and well organized. Organize the information in a logical manner by describing a building from the foundation up and from the exterior to the interior. Include specific facts and dates. The information should be consistent with the resource counts in Section 5 and the architectural classification and materials in Section 7. All of the contributing and noncontributing resources should be clearly identified and listed. Resources of state and local significance may be evaluated, but need to be clearly differentiated from those that contribute to the NHL themes and periods of significance for which the NHL is designated. The documentation must clearly distinguish which properties contribute to the national significance, and why, and which are significant at the state or local level. Resources that have national significance may also have state and locally significant values that may need to be documented in the nomination. These values must be clearly differentiated from those for which the resource is being nominated for NHL designation.

                                                                                      Historic districts usually require street by street description with a more detailed description of pivotal resources. Begin by outlining the general character of the group or district and then describe the individual resources one by one.

                                                                                      Describe the pivotal resources and the common types of resources, noting their general condition, historical appearance, and major changes. Follow a logical progression, moving from one resource to the next up and down each street in a geographical sequence or by street address.

                                                                                      Archeological nominations must also contain a brief description of the location and condition of previously excavated artifacts and collections made from the nominated property. This is a critical recognition of the importance of intact archeological collections to the scientific analyses and understanding of nationally significant archeological sites, both now and in the future.

                                                                                      Guidelines for Describing Properties


                                                                                      Buildings, Structures, and Objects

                                                                                      A. Type or form, such as dwelling, church, or commercial block.

                                                                                      B. Setting, including the placement or arrangement of buildings and other resources, such as in a commercial center or a residential neighborhood or detached or in a row.

                                                                                      C. General characteristics:

                                                                                      1. Overall shape of plan and arrangement of interior spaces.
                                                                                      2. Number of stories.
                                                                                      3. Number of vertical divisions or bays.
                                                                                      4. Construction materials, such as brick, wood, or stone, and wall finish, such as type of bond, coursing, or shingling.
                                                                                      5. Roof shape, such as gabled, hip, or shed.
                                                                                      6. Structural system, such as balloon frame, reinforced concrete, or post and beam.

                                                                                      D. Specific features, by type, location, number, material, and condition:

                                                                                      1. Porches, including verandas, porticos, stoops, and attached sheds.
                                                                                      2. Windows.
                                                                                      3. Doors.
                                                                                      4. Chimney.
                                                                                      5. Dormer.
                                                                                      6. Other.

                                                                                      E. Important decorative elements, such as finials, pilasters, barge boards, brackets, half timbering, sculptural relief, balustrades, corbelling, cartouches, and murals or mosaics.

                                                                                      F. Significant interior features, such as floor plans, stairways, functions of rooms, spatial relationships, wainscoting, flooring, paneling, beams, vaulting, architraves, moldings, and chimneypieces .

                                                                                      G. Number, type, and location of outbuildings, with dates, if known.

                                                                                      H. Other manmade elements, including roadways, contemporary structures, and landscape features.

                                                                                      I. Alterations or changes to the property, with dates, if known. A restoration is considered an alteration even if an attempt has been made to restore the property to its historic form (see L below). If there have been numerous alterations to a significant interior, also submit a sketch of the floor plan illustrating and dating the changes.

                                                                                      J. Deterioration due to vandalism, neglect, lack of use, or weather, and the effect it has had on the property's historic integrity.

                                                                                      K. For moved properties:

                                                                                      1. Date of move.
                                                                                      2. Descriptions of location, orientation, and setting historically and after the move.
                                                                                      3. Reasons for the move.
                                                                                      4. Method of moving.
                                                                                      5. Effect of the move and the new location on the historic integrity of the property.

                                                                                      L. For restored and reconstructed buildings:

                                                                                      1. Date of restoration or reconstruction.
                                                                                      2. Historical basis for the work.
                                                                                      3. Amount of remaining historic material and replacement material.
                                                                                      4. Effect of the work on the property's historic integrity.
                                                                                      5. For reconstructions, whether the work was done as part of a master plan.

                                                                                      M. For properties where landscape or open space adds to the significance or setting of the property, such as rural properties, college campuses, or the grounds of public buildings:

                                                                                      1. Historic appearance and current condition of natural features.
                                                                                      2. Land uses, landscape features, and vegetation that characterized the property during the period of significance, including gardens, walls, paths, roadways, grading, fountains, orchards, fields, forests, rock formations, open space, and bodies of water.

                                                                                      N. For industrial properties where equipment and machinery is intact:

                                                                                      1. Types, approximate date, and function of machinery.
                                                                                      2. Relationship of machinery to the historic industrial operations of the property.

                                                                                      A. Environmental setting of the property today and, if different, its environmental setting during the periods of occupation or use. Emphasize environmental features or factors related to the location, use, formation, or preservation of the site.

                                                                                      B. Period of time when the property is known or projected to have been occupied or used. Include comparisons with similar sites and districts that have assisted in identification.

                                                                                      C. Identity of the persons, ethnic groups, or archeological cultures who, through their activities, created the archeological property. Include comparisons with similar sites and districts that have assisted in identification.

                                                                                      D. Physical characteristics:

                                                                                      1. Site type, such as rockshelter, temporary camp, lithic workshop, rural homestead, or shoe factory.
                                                                                      2. Prehistorically or historically important standing structures, buildings, or ruins.
                                                                                      3. Kinds and approximate number of features, artifacts, and ecofacts, such as hearths, projectile points, and faunal remains.
                                                                                      4. Known or projected depth and extent of archeological deposits.
                                                                                      5. Known or projected dates for the period when the site was occupied or used, with supporting evidence.
                                                                                      6. Vertical and horizontal distribution of features, artifacts, and ecofacts.
                                                                                      7. Natural and cultural processes, such as flooding and refuse disposal, that have influenced the formation of the site.
                                                                                      8. Noncontributing buildings, structures, and objects within the site.

                                                                                      E. Likely appearance of the site during the periods of occupation or use. Include comparisons with similar sites and districts that have assisted in description.

                                                                                      F. Current and past impacts on or immediately around the property, such as modern development, vandalism, road construction, agriculture, soil erosion, or flooding.

                                                                                      G. Previous investigations of the property, including,

                                                                                      1. Archival or literature research.
                                                                                      2. Extent and purpose of any excavation, testing, mapping, or surface collection.
                                                                                      3. Dates of relevant research and field work. Identity of researchers and their institutional or organizational affiliation.
                                                                                      4. Important bibliographic references.
                                                                                      5. Repository or repositories where excavated collections are curated.

                                                                                      A. Present condition of the site and its setting.

                                                                                      B. Natural features that contributed to the selection of the site for the significant event or activity, such as a spring, body of water, trees, cliffs, or promontories.

                                                                                      C. Other natural features that characterized the site at the time of the significant event or activity, such as vegetation, topography, a body of water, rock formations, or a forest.

                                                                                      D. Any cultural remains or other manmade evidence of the significant event or activities.

                                                                                      E. Type and degree of alterations to natural and cultural features since the significant event or activity, and their impact on the historic integrity of the site.

                                                                                      F. Explanation of how the current physical environment and remains of the site reflect the period and associations for which the site is significant.


                                                                                      Architectural and Historic Districts

                                                                                      A. Natural and manmade elements comprising the district, including prominent topographical features and structures, buildings, sites, objects, and other kinds of development.

                                                                                      B. Architectural styles or periods represented and predominant characteristics, such as scale, proportions, materials, color, decoration, workmanship, and quality of design.

                                                                                      C. General physical relationship of buildings to each other and to the environment, including facade lines, street plans, squares, open spaces, density of development, landscaping, principal vegetation, and important natural features. Any changes to these relationships over time. Some of this information may be provided on a sketch map.

                                                                                      D. Appearance of the district during the time when the district achieved significance (see Period of Significance) and any changes or modifications since.

                                                                                      E. General character of the district, such as residential, commercial, or industrial, and the types of buildings and structures, including outbuildings and bridges, found in the district.

                                                                                      F. General condition of buildings, including alterations, additions, and any restoration or rehabilitation activities.

                                                                                      G. Identity of buildings, groups of buildings, or other resources that do and do not contribute to the district's significance. (See Determining Contributing and Noncontributing Resources for definitions of contributing and noncontributing resources.) If resources are classified by terms other than "contributing" and "noncontributing," clearly explain which terms denote contributing resources and which noncontributing. Provide a list of all resources that are contributing or noncontributing or identify them on the sketch map submitted with the form (see Sketch Map).

                                                                                      H. Most important contributing buildings, sites, structures, and objects. Common kinds of other contributing resources.

                                                                                      I. Qualities distinguishing the district from its surroundings.

                                                                                      J. Presence of any archeological resources that may yield important information with any related paleo-environmental data (see guidelines for describing archeological sites and districts).

                                                                                      K. Open spaces such as parks, agricultural areas, wetlands, and forests, including vacant lots or ruins that were the site of activities important in prehistory or history.

                                                                                      L. For industrial districts:

                                                                                      1. Industrial activities and processes, both historic and current, within the district important natural and geographical features related to these processes or activities, such as waterfalls, quarries, or mines.
                                                                                      2. Original and other historic machinery still in place.
                                                                                      3. Transportation routes within the district, such as canals, railroads, and roads including their approximate length and width and the location of terminal points.

                                                                                      M. For rural districts:

                                                                                      1. Geographical and topographical features such as valleys, vistas, mountains, and bodies of water that convey a sense of cohesiveness or give the district its rural or natural characteristics.
                                                                                      2. Examples and types of vernacular, folk, and other architecture, including outbuildings, within the district.
                                                                                      3. Manmade features and relationships making up the historic and contemporary landscape, including the arrangement and character of fields, roads, irrigation systems, fences, bridges, earthworks, and vegetation.
                                                                                      4. The historic appearance and current condition of natural features such as vegetation, principal plant materials, open space, cultivated fields, or forests.

                                                                                      Archeological Districts

                                                                                      A. Environmental setting of the district today and, if different, its environmental setting during the periods of occupation or use. Emphasize environmental features or factors related to the location, use, formation, or preservation of the district.

                                                                                      B. Period of time when the district is known or projected to have been occupied or used. Include comparisons with similar sites and districts that have assisted in identification.

                                                                                      C. Identity of the persons, ethnic groups, or archeological cultures who occupied or used the area encompassed by the district. Include comparisons with similar sites and districts that have assisted in identification.

                                                                                      D. Physical characteristics:

                                                                                      1. Type of district, such as an Indian village with outlying sites, a group of quarry sites, or a historic manufacturing complex.
                                                                                      2. Cultural, historic, or other relationships among the sites that make the district a cohesive unit.
                                                                                      3. Kinds and number of sites, structures, buildings, or objects that make up the district.
                                                                                      4. Information on individual or representative sites and resources within the district (see Archeological Sites above). For small districts, describe individual sites. For large districts, describe the most representative sites individually and others in summary or tabular form or collectively as groups.
                                                                                      5. Noncontributing buildings, structures, and objects within the district.

                                                                                      E. Likely appearance of the district during the periods of occupation or use. Include comparisons with similar sites and districts that have assisted in description.

                                                                                      F. Current and past impacts on or immediately around the district, such as modern development, vandalism, road construction, agriculture, soil erosion, or flooding. Describe the integrity of the district as a whole and, in written or tabular form, the integrity of individual sites.

                                                                                      G. Previous investigations of the property, including:

                                                                                      1. Archival or literature research.
                                                                                      2. Extent and purpose of any excavation, testing, mapping, or surface collection.
                                                                                      3. Dates of relevant research and field work. Identity of researchers and their institutional or organizational affiliation.
                                                                                      4. Important bibliographic references.
                                                                                      5. Repository or repositories where excavated collections are curated.

                                                                                      NHL Form Section 8. Statement of Significance

                                                                                      Applicable National Register Criteria


                                                                                      If the property has already been listed in the National Register of Historic Places, mark the criteria identified in the National Register nomination and any new criteria not already marked in the National Register nomination which apply to the national significance of the property.

                                                                                      Criteria Considerations


                                                                                      If the property was listed in the National Register with any applicable criteria considerations, mark those in addition to any new criteria considerations which apply to the national significance of the property if not covered by the National Register nomination.

                                                                                      National Historic Landmarks Criteria


                                                                                      Type in the National Historic Landmarks criteria for which the property qualifies for designation. Properties may be nationally significant for more than one criterion, but those qualifying criteria must be supported by the narrative statement of significance.

                                                                                      National Historic Landmarks Criteria Exceptions


                                                                                      Enter all National Historic Landmarks criteria exceptions which apply to the property. The criteria exceptions are a part of the NHL criteria and they set forth special standards for designating certain kinds of properties normally excluded from NHL designation. If no exceptions apply to the property, leave this section blank.

                                                                                      National Historic Landmarks Theme(s)


                                                                                      List the National Historic Landmarks theme and subtheme from The National Park Service's Thematic Framework for each criterion marked (See Appendix A). You may enter more than one nationally significant theme and subtheme but they must be supported by the narrative statement of significance. (See discussion in Chapter III.)

                                                                                      For a property nationally significant under Criterion 1, 3, or 5, select the theme and subtheme that relates to the historic event, ideal, or role for which the property is nationally significant. If Criterion 2 is being used, select the theme and subtheme in which the nationally significant individual made the contributions for which he or she is known or for which the property is illustrative. For a property nationally significant under Criterion 4, the themes and subthemes will most often be "Expressing Cultural Values: architecture, landscape architecture, and urban design" (for architecture) "Expressing Cultural Values: visual and performing arts" (for art) and "Expanding Science and Technology: technological applications" (for engineering). If Criterion 6 is being used, select the theme and subtheme that best describes the topic for which the site is likely to yield information.

                                                                                      Do not confuse the NHL theme with the historic function. Historic function relates to the practical and routine uses of a property. The theme(s) relates to the property's nationally significant contributions to the broader patterns of American history, archeology, architecture, engineering, and culture.

                                                                                      Areas of Significance


                                                                                      If the property has already been listed in the National Register of Historic Places, list those areas of significance identified in the National Register nomination in addition to those which apply to the national significance of the property if not already covered in the National Register nomination. If the property has not been listed in the National Register, select one or more areas of history in which the property is nationally significant. (See Figure 10.) Choose only areas that are supported by the narrative statement. Do not confuse area of significance with historic function which relates to the practical and routine uses of a property. Area of significance relates to a property's nationally significant contributions to the broader patterns of American history, archeology, architecture, engineering, and culture.

                                                                                      Historic Context


                                                                                      List the theme study or historic context or contexts within which the national significance of the property is being considered. This may be a theme study or historic context that has been or continues to be studied under past themes or a theme from the 1996 Thematic Framework. It may also be an area of significance or another historic context within which the property is being evaluated for NHL designation.

                                                                                      The classification of resources is important and fundamental to the comparative analysis necessary in making judgments of relative significance. It is also useful in determining where the property under consideration for NHL designation ranks when compared with other properties in the same theme or historical context. The NHL Survey staff and staff in the regional and support offices should be consulted for information about defining the theme or historic context and whether the property fits within a theme or historic context that has previously been studied.

                                                                                      You may enter more than one nationally significant theme or historic context, but they must be supported by the narrative statement of significance.

                                                                                      Period of National Significance


                                                                                      The period of national significance is the length of time when a property was associated with nationally significant events, activities, and persons, or attained the national characteristics which qualify it for designation as a National Historic Landmark. Therefore, enter the dates for one or more periods of time when the property attained this national significance. Some periods of significance are as brief as one day or year while others span many years and consist of beginning and closing dates.

                                                                                      Base the period of national significance on specific events directly related to the national significance of the property. For the site of a nationally significant event, the period of significance is the time when the event occurred, while the period of significance for properties associated with nationally significant historic trends is the span of time when the property actively contributed to the trend. For properties associated with nationally significant persons, the period of significance is the length of time of that association. Architecturally significant properties use the date of construction and/or the dates of any significant alterations and additions for the period of significance. For precontact properties, the period of significance is the broad span of time about which the site or district is likely to provide information. The property must possess historic integrity for all periods of national significance listed.

                                                                                      Continued use or activity does not necessarily justify continuing the period of significance. The period of significance is based solely upon the time when the property made the nationally significant contributions or achieved the national character on which the significance is based. Fifty years ago is used as the closing date for periods of significance where activities begun historically continued to have importance and no more specific date greater than 50 years ago can be defined to end the historic period. For some properties, such as those relating to the Cold War or the Civil Rights Movement, the period of significance may be within the last 50 years. However, if the closing date of the period of national significance is less than 50 years ago then you will have to apply Criteria Exception 8 to the property.

                                                                                      Nationally Significant Dates


                                                                                      A nationally significant date is the year when one or more major events directly contributing to the national significance of a historic property occurred. Therefore, enter the year of any events, associations, construction, or alterations that add to its national significance and contribute to qualifying the property for designation as a National Historic Landmark. A property may have several dates of significance all of them, however, must fall within the periods of significance. In addition, the property must have historic integrity for all the significant dates entered.

                                                                                      The beginning and closing dates of a period of significance are "significant dates" only if they mark specific events directly related to the national significance of the property. For properties using Criterion 4, the date of construction is a significant date but list the dates of alterations only if they contribute to the national significance of the property. Some properties may not have any specific dates of significance. In these cases, enter "N/A."

                                                                                      Significant Person


                                                                                      Complete this item only if the property is being considered under Criterion 2. Enter the full name, last name first, of the nationally significant person with whom the property is importantly associated. Do not list the name of a family, fraternal group, or other organization. Enter the names of several individuals in one family or organization only if each person is nationally significant and made nationally significant contributions for which the property is being designated. List the name of the property's architect or builder only if the property's nationally significant association is with the life of that individual, such as the nationally significant architect's home, studio, or office.

                                                                                      Cultural Affiliation


                                                                                      Complete this item only if the property is being considered under Criterion 6. Cultural affiliation is the archeological or ethnographic culture to which a collection of artifacts or resources belongs. It is generally a term given to a specific cultural group for which assemblages of artifacts have been found at several sites of the same age in the same region.

                                                                                      For Native American cultures, list the name commonly used to identify the cultural group (such as Hopewell or Mississippian), or list the period of time represented by the archeological remains (such as Paleo-Indian or Late Archaic).

                                                                                      For non-Native American historic cultures, list the ethnic background, occupation, geographical location or topography, or another term that is commonly used to identify members of the cultural group (such as Appalachian, Black Freedman, or Moravian).

                                                                                      For properties nationally significant for criteria besides Criterion 6, list important cultural affiliations under areas of significance.

                                                                                      Architect/Builder


                                                                                      List the full name, last name first, of the person(s) responsible for the design or construction of the property. This includes architects, artists, builders, craftsmen, designers, engineers, and landscape architects. Enter the names of architectural and engineering firms, only if the names of specific persons responsible for the design are unknown. If the property's design is derived from the stock plans of a company or government agency, list the name of the company or agency (such as the U.S. Army or the Southern Pacific Railroad). The names of the property owners are listed only if they were actually responsible for the property's design and/or construction. If the architect or builder is not known, enter "unknown."

                                                                                      Narrative Statement of Significance


                                                                                      Explain how the property meets the National Historic Landmarks criteria by drawing on facts about the history of the property and the nationally historic trends that the property reflects. The goal of the statement is to make the case for the property's national historical significance and integrity. The statement should explain in narrative form the information which justifies the NHL criteria, the criteria exceptions, the NHL themes and historic context, the significant person(s), the period of significance, and the significant dates. This narrative should explain why the nominated property stands out among its peers. The statement should be concise, factual, well-organized, and in paragraph form. The information contained in the statement should be well-documented with proper footnotes. (Use a standard scholarly footnote style such as that found in The Chicago Manual of Style published by the University of Chicago Press or in A Manual of Style by Kate L. Turabian also published by the University of Chicago Press.) Include only information pertinent to the property and its eligibility.

                                                                                      The statement should begin with a summary statement of significance which states simply and clearly the reasons why the property meets the NHL criteria. Provide brief facts that explain the way in which the property was important to the history of the United States during the period of significance and mention the nationally significant themes and historic contexts to which the property relates.

                                                                                      Historic context is information about historic trends and properties grouped by an important theme in the history of the nation during a particular period of time. Because historic contexts are organized by theme, place, and time, they link historic properties to important historic trends. In this way, they provide a framework for determining the significance of a property and its eligibility for designation as a National Historic Landmark. A knowledge of historic contexts allows applicants to understand a historic property as a product of its time and as an illustration of aspects of heritage that may be unique, representative, or pivotal.

                                                                                      Identify specific associations or characteristics through which the property has acquired national significance, including historic events, activities, persons, physical features, artistic qualities, architectural styles, and archeological evidence that represent the historic contexts within which the property is important to the nation's history. Specifically state the ways the property meets the qualifying NHL criterion and any criteria exclusions.

                                                                                      Using the summary paragraph as an outline, make the case for national significance in the subsequent paragraphs. Begin by discussing the chronology and historic development of the property. Highlight and focus on the events, activities, associations, characteristics, and other facts that relate the property to its national historic contexts and are the basis for its meeting the NHL criteria.

                                                                                      For each NHL theme and historic context discuss the facts and circumstances in the property's history that led to its national significance. Make clear the connection between each theme, its corresponding criterion, and the period of significance. This discussion of the NHL themes and historic context should explain the role of the property in relationship to broad nationally historic trends, drawing on specific facts about the property. The history of the community where the property is located as it directly relates to the property should also be described in order to orient the reader to the property's surroundings and the kind of community or place where it functioned in the past. Highlight any notable events and patterns of development in the community that affected the property's national history, significance, and integrity. Describe how the property is unique, outstanding or exceptionally representative of a nationally significant historic context when compared with other properties of the same or similar period, characteristics, or associations.

                                                                                      The preparer should be selective about the facts presented considering whether they directly support the national significance of the property. Narrating the entire history of the property should be avoided. Rather, the statement should focus only on those events, activities, or characteristics that make the property nationally significant. Dates and proper names of owners, architects or builders, other people, and places should be given. The preparer should keep in mind the reader who will have little or no knowledge of the property and its historic context, or its location.

                                                                                      Values of state and local significance may be mentioned and discussed, but need to be clearly differentiated from those that contribute to the NHL themes and period of significance for which the NHL is being considered for designation. Resources that have national significance may also have state and locally significant values that may be documented in the nomination but these values also must be clearly differentiated from those for which the resource is being nominated for NHL designation.


                                                                                      Caveats about near-term employment impacts: labor intensity of infrastructure investment

                                                                                      We cautioned above that these estimates of the near-term boost provided by infrastructure investment are highly context-dependent. So, these estimates would be totally uninformative about a program of infrastructure investments that, say, began in 2020, a year in which the overall state of the economy is impossible to predict with any certainty. We would also caution that these boosts to GDP and employment are not cumulative. Under an infrastructure investment program that boosts this spending by, say, $30 billion annually for 10 years, these boosts to GDP and employment would manifest in the first year (roughly, some of the increase could take a bit longer to manifest), but would not continue to rise thereafter. These estimates to the near-term boost to GDP and employment are increases in the level, not the growth rate, of these variables. This is because spurring increases in the growth of GDP or employment from public investment would require a steadily increasing contribution from year to year. So, once policymakers assign, say, $500 billion in total public investment in 2014, the only way public investment can boost the level of GDP in 2015 is to increase that year’s public investment flow. Making the same public investment effort each year for a number of years only increases the level of GDP in the initial year, and then provides no further boost thereafter.

                                                                                      A further caution is that there is one possible way that these macroeconomic estimates of the employment impacts of infrastructure investments could be slightly biased: if the labor intensity of such investments differed markedly from the economy-wide labor intensity of production that these estimates are implicitly based on. In Figure E, we quickly check if such issues are severely biasing our results by comparing the average labor intensity (jobs created directly, and overall, including through supplier effects) of our three scenarios of infrastructure investments with overall measures of labor intensity. We find that infrastructure investments are indeed less labor-intensive than economy-wide averages each $1 million in infrastructure spending generates roughly 20–25 percent fewer jobs than each $1 million in general economic output.

                                                                                      Direct and total jobs supported by $1 million in final demand, economy-wide average and under three infrastructure investment scenarios

                                                                                      Direct jobs Direct and supplier
                                                                                      Economy average 9.83 12.67
                                                                                      Scenario 1 6.01 10.63
                                                                                      Scenario 2 6.52 9.65
                                                                                      Scenario 3 5.87 8.94

                                                                                      The data below can be saved or copied directly into Excel.

                                                                                      The data underlying the figure.

                                                                                      Note: This chart shows the relative labor intensity of infrastructure investment.

                                                                                      Source: Author’s analysis of data from Employment Requirements Matrix (ERM) data supplied by the Bureau of Labor Statistics

                                                                                      Copy the code below to embed this chart on your website.

                                                                                      This decreased labor intensity is driven by a couple of factors.

                                                                                      First, manufacturing activity in the United States is far less labor-intensive than economy-wide averages. There has been extraordinarily rapid automation and capital-deepening in this sector for decades. Globalization has surely contributed to this in the United States, as standard trade theory argues that increased opportunities for trade should (and almost surely did) lead capital-abundant countries like the United States to focus tradable-goods production in capital-abundant industries and shed production in labor-intensive sectors. One, however, should be careful to not assume this move toward capital-intensive production holds generally. The same logic of globalization that pushes U.S. production toward capital-intensive sectors works in reverse for many other countries. Labor-abundant countries (like those in much of the global South) should actually increase production in labor-intensive sectors as a result of global integration.

                                                                                      Second, the construction sector is a very input-intensive sector. But the problem from the perspective of raw job creation is that many of these inputs come from the very capital-intensive manufacturing sector, and this leads to total labor intensity of construction spending that is even a shade below economy-wide averages as well.

                                                                                      This argues that a strategy aimed at maximizing the number of jobs generated through infrastructure investments needs to carefully pick sectors that receive direct spending flows. Of course, since construction and manufacturing industries both are notably less labor-intensive than economy-wide averages (and utilities even more so), it may be quite hard to find traditional infrastructure projects that will generate a greater-than-average number of jobs through direct and supplier channels.

                                                                                      However, the lower number of jobs generated through direct and supplier channels could well be counterbalanced, at least in part, by the higher wages and capital incomes generated through such spending. This is true essentially by definition: If $1 million in final demand for industry X supports fewer jobs than $1 million in final demand for industry Y, then industry X must either have higher wages or see more of the income generated through final demand flow to capital owners. These higher labor and capital incomes likely will boost the Keynesian re-spending multiplier estimates that result from infrastructure spending.

                                                                                      Additionally, we should note here an important distinction, that between the implicit employment multiplier of a given amount of spending versus the implicit employment multiplier of a specific job. Because manufacturing and construction activity in the U.S. economy are capital and intermediate-input intensive, this means that the direct and supplier jobs supported by a given spending flow are lower than if that spending flow went into other industries. But, the high capital and intermediate input intensity means that each job in manufacturing and construction is associated with the support of many more jobs in other sectors. To say it another way, it might cost a bit more to generate a job in construction and manufacturing, but this job will support more jobs in ancillary sectors than a job created more cheaply in other sectors. Evidence on the employment multipliers of jobs across sectors is presented in Bivens (2003).

                                                                                      It is important to note again that the estimates of near-term economic activity and employment in this section are highly context-dependent and will not be valid during periods when there is substantially less economic slack. The next section will look at the types of jobs likely to be created through these scenarios of infrastructure investment, and these estimates of the structural employment composition of infrastructure investments are much less context-dependent and should hold for investments undertaken over at least the next decade and do not depend on the extent of economic slack.


                                                                                      Methods and materials

                                                                                      Description of the study area

                                                                                      This study was conducted in Addis Ababa, which is the capital city of Ethiopia. Addis Ababa is a chartered city having three layers of government: one municipality, ten sub-cities and 116 districts/Woredas (Fig. 1). The total area of the city is 526.99 km square. The city serves as a social, economic and political center for the country. Its total population as of August 2019 estimated to be 4,592,000 with an annual growth rate of 4.4 percent (CSA 2019). This constitutes approximately 20 percent of Ethiopia’s urban population. The population growth in the city is far out pacing economic growth, resulting in a large slum and squatter settlements. Until recently, slum houses occupied more than 75% of the city (CSA 2017).


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