The previous post reported that the Census of Missouri Public Water Systems – 2015 found 2,722 public water systems in Missouri. This post looks at Missouri’s 2013 Annual Compliance Report of Missouri Public Drinking Water Systems. It is a summary report, detailed reports are published by the individual public water systems. It often takes many months to compile, so the most recent Compliance Report is often a year or more behind the most recent Census.
A public water system is one that provides water to at least 15 service connections, or to an average of at least 25 people for at least 60 days each year. Community Systems (CWS) supply water to the same population year-round. Non-Transient Non-Community Water Systems (NTNCWS) supplies water to at least 25 of the same people at least 6 months per year, but not year-round. An example might be a school that has its own water system. A Transient Non-Community Water System (TNCWS) provides water in a place where people do not remain for long periods of time. Examples might include gas stations or campgrounds that have their own water systems.
The amount of treatment that water must receive differs depending on the source of the water. Surface water and underground water under the direct influence of surface water are more vulnerable to contamination, so they receive more treatment. Underground water from aquifers not under the direct influence of surface water tend to contain water that is heavily filtered by the rock through which it seeps. Sometimes, the seepage is so slow that the water is old, predating most forms of modern contamination.
The top graph at right shows the percentage of community water systems that meet all health-based requirements by year. The bottom graph shows the number of violations involving E. Coli or acute coliform levels. Non-compliance can result from many factors – from broken pipes, to human error, to systems that are inadequate in the first place. But 95.3% of the population was served by water systems that had no violations during the year. Ninety-five percent is the EPA goal, so Missouri met the goal. However, the rate slipped by about 0.4% between 2012 and 2013. Given that Missouri’s population was estimated to be 6,044,917 in 2013, that slippage represented over 24,000 people.
Missouri Department of Natural Resources. 2015. Census of Missouri Public Water Systems, 2015. http://dnr.mo.gov/pubs. This URL will take you to a long list of publications available from MoDNR. Scroll down to Public Drinking Water to find the census reports.
Missouri Department of Natural Resources. 2013 Annual Compliance Report of Missouri Public Drinking Water Systems. http://dnr.mo.gov/pubs. Published 2014-11-18. This URL will take you to a long list of publications available from MoDNR. Scroll down to Public Drinking Water to find the compliance reports.
United States Census Bureau. State and County Quick Facts: Missouri. http://quickfacts.census.gov/qfd/states/29000.html.