Prioritize Locations for Construction

Prioritize Locations
for Construction

Overview:

This tool evaluates all possible locations that a water point could be constructed in a given district and evaluates how many people that are not near an existing water point (regardless of functionality) could gain access if a water point was constructed in that location.

Illustrative Uses:

Identify locations to build new water points
Evaluate the relative benefit of building new water points compared to rehabilitating existing water point

Instructions:

Click “OK” on the welcome message
Select “New Locations” from the choices at the top. You may need to press the down arrow to get to “New Locations”
In “Administrative Zone”, type in the name of the district you are looking for. If there is not enough data in that district, the tool may give you an error
In the “Number of Candidates”, select the number of water point construction locations you would like to recieve
Select the access distance. This is the furthest people can be from a water point to be considered to have access. Note: WPDx recommends leaving the access distance at 1000m.
Click “Execute”
It may take about 10-15 minutes to process. Note: This tool is not using significant amounts of data or bandwidth during this time. Instead, it is waiting for the server to complete the analysis.
You can see the results on a satellite map by clicking the four squares in the top left of the map and selecting “Imagery with Labels”.
You can download the data by clicking the link under “Output CSV”
In the CSV, the “Pop_Served” shows the number of additional people (not yet reached) that are estimated to be reached if that water point was rehabilitated.

Methodology:

This tool begins by importing the latest available data from WPDx for the given district. Next, it imports high resolution population maps of the district from ESRI’s Living Atlas. This provides an estimate of the number of people living within every 250m x 250m grid square in the district. The tool then draws a circle around all water points with a radius equal to the access distance provided. The value of the population grid squares within the access circle are set to 0, as all of the people within the access distance of a water point could potentially have water access using existing infrastructure. The tool then draws a circle around the center of every 250m x 250m with a radius equal to the access distance provided and adds up the total population of all grid squares within the circle. All possible locations are ranked based on the population that could be served, and the data is provided for the top locations, based on the number of candidates provided.

Limitations:

This analysis is based on the latest available data, and population estimates from ESRI. Any water points that have been broken, rehabilitated, or constructed for which the data is not in WPDx have not been included in this analysis. Additionally, household connections are not captured in WPDx. While large urban areas are removed from the analysis if they reach a specified population density, smaller piped schemes with household connections may be missed. As a result, peri-urban areas may be identified as optimal locations, even if those communities are already served by household connections.