Health & Property Impacts
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Onsite Wastewater Treatment Systems: Health & Property Impacts

Health and Property Impacts of Compliant Onsite Wastewater Treatment Systems

Onsite wastewater treatment systems (OWTS), or septic systems, that are non-compliant with existing regulations can have significant, detrimental impacts on public health, the environment, and property value.

Property Value

Septic systems are not built to last a lifetime. Over 80% of systems need repair before they reach 30 years of age in order to continue properly treating sewage. Upkeep of a septic system includes regular attention.

Groundwater Contamination

Septic systems are the second most frequently cited source of groundwater contamination in our country.

Failing, unapproved, and aging septic systems pose a serious risk to our water when bacteria and other pollutants leak into our waterways.
Recent data indicates that E. coli bacteria and other pollution may already be in our water. Areas of Boulder Creek indicate the presence of fecal matter and bacteria levels that exceed water quality standards. Both Boulder Creek and Coal Creek are on the Environmental Protection Agency’s (EPA) list of impaired waterways for E. coli.

Find out more about what’s being done to maintain our watershed health.

Risk Factors

Many factors put some areas with septic systems at greater risk than others, including the age of the system, how many other systems are nearby, the type of soil and slope of the ground the system is on, and the distance of the system from drinking or groundwater.


Many homes with septic systems depend on private wells for their water supply. This means water wells and septic systems live in close proximity. The two can be a dangerous mix if your septic system isn’t approved and properly maintained.

Get more information about maintaining your well and testing it regularly.

Please Note: This information is intended to provide a better understanding of the functions of onsite wastewater treatment and the need for proper design, installation, and maintenance. Always consult a licensed professional or public health official with questions regarding the engineering, installation, and servicing of onsite wastewater systems.

Contact Us

SepticSmart Program

Main: 303-441-1564
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