The design and maintenance of an onsite wastewater treatment system (OWTS), commonly referred to as a “septic system,” are two important responsibilities for a property owner concerned about Lake George water quality.
Property owners whose homes are serviced by an onsite wastewater treatment system (OWTS), commonly referred to as a septic system, in the Lake George watershed should focus on the design, siting and maintenance of the system. Regular system maintenance is critical for residents and businesses. Landowners are also encouraged to consider an upgrade to a new enhanced system, designed to remove nutrients before they reach the groundwater.
The Importance of Design and Location
A licensed professional engineer must be used for OWTS design for new systems as well as upgrades to existing systems. A well administered design process will produce a treatment system that will protect water quality and perform well for years if properly maintained. Critical aspects of the design process include the following:
- The location of a septic system is a critical part of site design. Soil considerations are the most important factor for location of a septic system.
- Pump out your septic tank every two or three years, depending on use, to not only help protect the quality of the lake, but also to ensure system efficiency.
- Many improved septic system designs that maximize water quality protection are available.
- Site appraisal: During a site appraisal, land conditions, such as wetlands, steep slopes, and separation requirements should be evaluated to determine the best location of an OWTS. Figure 11 shows a good location for an OWTS. The site characteristics should dictate the general location and orientation. In addition, there are maximum-slope considerations that must be made, which affect the cost of construction, the environmental impact and overall system effectiveness. State and local regulations set separation distances from wells, property lines and water bodies. These are important determinations to minimize risks to public health and the environment.
- Soil investigation: In a soil investigation, a licensed engineer should evaluate the soil type to determine what type of OWTS should be used, where it should be sited, and to determine adequate depth to seasonal high groundwater and/or bedrock. A percolation test must be performed to determine soil permeability. A larger area will be required to absorb wastewater in conditions with slow soil permeability.
- Design flow: The design flow is the estimated wastewater generated from a residence based on the number of bedrooms and accessory uses, such as hot tubs, garbage disposal, home office, home business, among other factors. Calculating design flow is necessary to determine the size of the leach field needed for a system. It is primarily based on the number of bedrooms in a house, including additional rooms that could be converted to bedrooms (e.g., expansion attics, basements, dens and recreation rooms). The OWTS should be built to a size appropriate for realistic use.
The Importance of Maintenance
If an OWTS is well sited and designed, it will help to protect the water quality of Lake George for years to come. Once installed, it’s important to maintain and regularly pump out the system. The function of the septic tank is to settle solids from the wastewater, which requires routine pumping to prevent solid buildup. Failure of proper maintenance can damage the overall system, which could require a costly upgrade or replacement of a clogged absorption field that no longer functions. Here are key points for OWTS maintenance:
- Know the location of your septic tank and absorption field. If the location of a tank is unknown, then the system is not being maintained and serviced. It’s important to know the type and age of the system and its maintenance requirements. It’s also useful to have the original permits from your local town or NYS Department of Health to determine when the system was installed or upgraded.
- Routinely pump out your septic tank. Typically, an OWTS should be pumped out every two or three years. This might differ for seasonal residences or commercial facilities depending on use. For a list of local haulers, see safesepticsystems.org.
- Inspect the structure of the tank after pump out. During a structural inspection, your tank should be checked for visible component failures. A septic tank should contain baffles and/ or tees installed at the inlet and outlet of the tanks to prevent direct flow through the tanks, allow solids to settle and prevent scum and solids from leaving the tank. If present, the discharge filter should be checked on the outlet pipe. The tank should be watertight, with no cracks or corrosion, to prevent direct discharge of wastewater that can pollute the groundwater.
- Inspect the tank for water entering after pump out. During the inspection, there should be no water running in the home. If water is observed to be flowing into the tank during the inspection, this indicates there is a leak in the piping that leads to the tank. Water draining back into the system through the outlet pipe indicates potential absorption field clogging, which would require further inspection.
- Beware of tank additives. Many products are advertised to “help” the operation and effectiveness of an OWTS. Beware. Additives can contaminate groundwater from chemicals, corrode a system, or create a situation where settled solids leave a tank resulting in clogged absorption fields. A properly designed, sited, installed and maintained septic system will need no chemical additives.
- Care for an absorption field. The absorption field is an important part of the system and must be maintained. Do not plant trees or shrubs on the field to prevent damage from roots. Do not drive, park or pave over your absorption field. This can compact soils, which reduces infiltration or damages pipes.
Enhanced Designs Help Increase Lake George Water Quality
A conventional OWTS consists of a standard septic tank, where primary treatment of solid settling occurs, and an absorption field, where wastewater is filtered and oxidized. There are many types of enhanced treatment waste systems available today that can greatly increase the quality of discharge by removing a larger percentage of nutrients, such as nitrogen. These systems provide additional treatment either within the septic tank structure or through filters before discharge enters an absorption field. For a list of enhanced treatment systems that are appropriate for Lake George, please visit safesepticsystems.org.