SUB-PROBLEMS INCLUDING LEADING TO IMPAIRMENT AND BEST PRACTICES FOR PUBLIC DRINKING WATER TREATMENT PLANTS
Location, Source, and Preliminary Pretreatment for Raw Water
Source water has to be evaluated in the following way. Determine the source water assessment area for all types of drinking water supplies whether they are groundwater or surface water. For groundwater, use available information about the flow and recharge area. Remember that as the use of groundwater increases because of increased wells, the flow and recharge area will broaden considerably. It is from this area typically that contaminants can readily enter the groundwater supply.
However, fractured limestone or other types of fractured underground areas can create situations where contaminants may flow for many miles underground into the typical groundwater supply. For surface water, determine the watershed upstream from the intake valve and plot it on a topographical map showing all potential sources of pollution and the nature of the pollution within the watershed area. Establish an inventory of all the potential sources of pollutants and quantity that can contaminate the water supply, whether it is groundwater or surface water. These pollutants may come from landfills, fuel or chemical storage tanks, septic systems, runoff from streets, lawns, farms, etc. of fertilizer and pesticides, sludge disposal, businesses and industry, etc. Determine the likelihood of contamination of the water supply and how best to prevent or mitigate the situation. Provide all information to the public as well as the appropriate agencies in order for them to make proper decisions on the best way to utilize the water source and its treatment process. This may involve multiple governmental jurisdictions and should be determined on a regional basis. (See endnotes 5 and 12.)