Strategies for Rural Development in Areas with Limited Public Infrastructure: Alternative Septic Systems
Why Manage?
Although it is difficult to measure and document specific cause-and-effect relationships between the performance of onsite wastewater treatment systems and the quality of water resources, it is widely accepted that improperly managed septic systems contribute to water quality degradation in both groundwater and surface water. In the National Water Quality Inventory’s 1996 Report to Congress, state agencies were asked to designate the top ten potential contaminant threats to their groundwater resources. The second most frequently cited contamination source was improperly functioning septic systems. The 1996 Report to Congress also noted that onsite systems in Maine directly discharged the largest volume of nonpoint source pollution into the subsurface environment, including contaminants such as nitrates, bacteria, viruses, and toxic chemicals from household products. Most of the older grandfathered cesspool systems (and “straight pipe” plumbing discharges directly to surface waters) that contributed to this poor assessment have since been replaced with modern onsite septic systems, which actively treat the wastewater in the septic tank and the leach field before discharging it to the soil for further treatment. Nonethleless, decentralized wastewater system managers need to establish treatment standards and practices that will reduce or eliminate the potential for nearby groundwater and surface water contamination by the wastewater discharges from their system.
Improperly managed onsite septic systems can significantly degrate the water quality of surface waters such as rivers, lakes, and coastal waters. Phosphorus loading from onsite systems has been widely identified as a cause of cultural eutrophication of Maine’s lakes. Eutrophication is a natural process caused by nutrient enrichment of aquatic systems, but it can be greatly accelerated by so-called “cultural” inputs from human activities, including agricultural practices, exposed soil erosion, and wastewater disposal from both onsite and centralized systems. The availability of additional nutrients can result in the growth of undesirable algae blooms, which in turn leads to the development of hypoxic (low dissolved oxygen) zones that kill off fish and other aquatic species, some of which are already threatened or endangered in Maine.
Bacterial contamination from failed or failing onsite septic systems has also been cited as a significant cause of impairment of Maine’s marine and estuarine waters. Although the reasons for any single onsite system failure may be attributable to errors or shortcomings at any point in the wastewater treatment process – siting, design, construction, operation, or maintenance – it is ultimately the absence of comprehensive management programs with oversight over all of these processes that prevents onsite and clustered systems from reaching their full potential as effective and reliable wastewater treatment strategies.
More detailed information on Management models and practices is available in the following handbooks and resource materials.
Related Work Plan Components
- Climate Change and Infrastructure Resilience
- Modernizing Communications/Electric Utility Infrastructure
Workgroup Contacts
In Aroostook County: Jay Kamm, Ken Murchison, Joella Theriault
In Washington County: Judy East
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