On October 18, 1972, U.S. Congress passed the Federal Water Pollution Control Act, setting the goal of eliminating the discharge of pollutants into the nation’s waters. This law has been revised and challenged, but the goal remains the same. This law set into motion the steady progress toward eliminating the discharge of water pollutants by establishing the National Pollutant Discharge Elimination System (NPDES). Industries, cities and the federal government have invested heavily in making this goal a reality.
As the United States gets closer to achieving the national goal, small communities and rural areas are facing the challenge. Fortunately, many options are available to small communities to meet the goal of no discharge of pollutants. The options fall into three major categories.
Collect wastewater and treat to remove all pollutants before discharge to a stream.
When considering the stream discharge option, the following components are necessary:
- a sewer system to collect all of the wastewater from individual homes
- a body of water to discharge the treated wastewater
- a high-technology treatment plant that can remove all water pollutants
- attentive and highly trained people to operate and manage the collection and treatment system
Collect wastewater and treat before reuse through irrigation.
When considering the irrigation option, the following components are necessary:
- a sewer system to collect all the wastewater from individual homes
- land and an irrigation system
- a medium-technology treatment plant that can reduce odors and pathogens
- attentive and trained people to manage the collection, treatment and irrigation system
Build, operate and manage small treatment systems onsite for each individual home.
When considering the onsite wastewater management option, the following components are necessary:
- appropriate soil and lot size for onsite wastewater treatment and dispersal system
- appropriate technology treatment system to match site conditions
- attentive and trained people to manage the onsite treatment systems
No sewer system is needed to collect all of the wastewater from individual homes.
The third option, onsite wastewater management, is attractive to small communities and rural areas because it eliminates the need for a high-cost sewer system. In developing a new wastewater system, the construction of the sewer system is the most expensive part, costing millions of dollars to serve a few hundred homes. Sewer systems can also have unintended and undesirable impacts on development patterns in a rural area.
All three options require attentive and trained people to manage the treatment systems. Unfortunately, most individual septic systems and other onsite wastewater treatment and dispersal systems do not receive the management they require. Table 1 summarizes the minimum level of management recommended for onsite wastewater treatment systems.
|Table 1. Minimum Technology and Management Recommendations Suited to Ohio’s Soil Natural Resource.|
|Soil Natural Resource||Onsite Treatment Technology||Level of Management|
|Deep, Permeable Soil
(at least 3 feet to a limiting condition*)
|Soil absorption (leaching) system with septic tank and alternating fields||Annual inspection to check for ponding. Alternate field as needed. Inspect septic tank; clean filter and pump as needed.|
|Shallow, Permeable Soil
(1 foot to 3 feet deep to a limiting condition)
|Mound system with septic tank||Two inspections per year to flush pipes and check for ponding. Maintain pump and control system. Inspect septic tank; clean filter and pump as needed.|
|Very Shallow and Slowly Permeable Soil
(at least 8 inches deep to a limiting condition)
|Onsite irrigation with onsite treatment/disinfection system||Two inspections per year to inspect and maintain treatment system; add disinfectant and service irrigation system.|
|*Limiting conditions are bedrock, sand and gravel layers; dense and impermeable layers; and water tables. To learn more about limiting layers, check Ohio State University Extension fact sheet AEX-745, Using Soil to Remove Pollutants From Wastewater.|