The first step in conducting an assessment of a public drinking water system is to define the source water assessment area, or the area which contributes water to the public drinking water intake. The map below is a hypothetical example of what the source water assessment area for Almont, CO might look like. A source water assessment area for a surface water system is the entire watershed upstream from the public drinking water intake. Source water assessment areas for wells are based on the movement of water through the aquifer over a specified period of continuous pumping.
Public drinking water system intakes or well locations other than Almont's are also indicated on this map. Each one of these public water systems would also have its own source water assessment area. Public water systems serve water to the public, and are classified as either community or non-community systems. Examples of community systems on this map would be Crested Butte, Mount Crested Butte, Crested Butte South, and Almont. An example of a non-community system within Almont's source water assessment area would be a U.S. Forest Service campground.
Once the source water assessment area for a public drinking water system has been determined, an inventory of potential contamination sources which could affect the drinking water will be conducted. Potential sources of contamination will be identified by checking data bases maintained by state and federal regulatory agencies, such as the Colorado Department of Public Health and Environment and the U.S. Environmental Protection Agency. Once the information from these data bases is shown on a map of the source water assessment area, communities or public water systems will have an opportunity to add information about historical or local contamination sources that might otherwise be missed.
The next map is a hypothetical example of what the contamination inventory map might look like for Almont's source water assessment area. Please note that some contamination sources have been added for the purpose of demonstration.
When the contaminant inventory is complete, the public water system will know what contaminants could possibly enter the drinking water and where these contaminants may be coming from. This and additional information will be used to analyze the susceptibility of the public drinking water system to these contamination sources. With the completion of the susceptibility analysis, assessment results for all public drinking water systems in Colorado must then be publicized. Assessment results will be available on this web site, including maps of the source water assessment areas, showing the intakes or wellheads and the relative locations of potential sources of contamination, and the results of the susceptibility analyses.