Groundwater pollution risk estimation

When preparing an SFD graphic for a city, you can use this page to help estimate the risk of groundwater pollution. Answering these six questions will give you an estimate of whether the risk of groundwater pollution is low or significant.
You can then apply the result in Step One of the SFD Graphic Generator to help you select the appropriate sanitation system from the SFD selection grid. The page can be used repeatedly to model different areas of a city where different sanitation systems maybe in use.

Q1: Vulnerability of the aquifer

A: What is the rock type in the unsaturated zone?
(see Supplementary information in Table 1 )
B: What is the depth to the groundwater table?
(see Supplementary information in Figure 1 )
Q1 Risk Outcome

Q2: Lateral separation

A: What is the percentage of sanitation facilities that are located <10m from groundwater sources?
(see Supplementary information in Figure 1 )
B: What is the percentage of sanitation facilities, if any, that are located uphill of groundwater source?
Q2 Risk Outcome

Q3: Water supply

What is the percentage of drinking water produced from groundwater sources?

Q4: Water prodution

What is the water production technology used?
(see Supplementary information in Table 2 )

Overall Risk

Overall Risk Outcome




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