When someone is building a new house, planning can be very exciting. If the site does not have a sewer connection available, a septic system needs also needs to be built. Installing the right septic system is important, and there is much to consider during the design process.
First, septic system regulations should be addressed. Other things to consider include:
- The terrain of the property and landscaping.
- Septic tank location and size needed.
- Drain field size.
All Septic & Sewer has compiled a list of key elements to consider when designing a septic system, whether for a new build or an addition. Continue reading for more info.
Septic System Design Regulations
Septic systems are also called On-site Sewage Systems (OSS). The Washington State Department of Health says there are around 950,000 of these systems in the state. Septic systems that are properly designed according to state regulations keep people and the environment safe and healthy.
Consider The Terrain And Landscaping During The Design Process
Level areas are best for a septic system. Placing a septic tank at the bottom of a hill or other sloped area can cause problems. Water coming down the slope from hard rain can flood the tank or drain field. Flooding can cause the wastewater to come back into the house.
Soil type is also important when putting together a septic system design. The soil of the drain field needs to have a high absorption rate to treat the water coming out of the septic tank. Soils with a high clay or gravel content will not treat the effluent properly. Areas with a high water table require a specific kind of drain field so effluent will not mix into the groundwater without treatment.
Landscaping over the septic tank and drain field are also important. Planting grass or groundcover that is drought tolerant is the best choice. Plants and trees with large root systems can damage the drain field pipes. Nothing heavy, like swing sets or sandboxes, should be placed above the drain field for the same reason.
Septic Tank Size And Placement
Having the correct size septic tank is important. If it is too small, the septic tank will not be able to handle the amount of wastewater coming from the house. An overfull septic tank can cause the wastewater to come back to the house and flood.
The septic tank size can be decided by the number of bedrooms in the house or the square footage of the house. The minimum size septic tank in the state of Washington for three or fewer bedrooms is 1000 gallons. The minimum requirement for a four-bedroom house is a 1250 gallon septic tank. For each added bedroom, the septic tank must hold an additional 250 gallons.
During the septic system design process, figuring out where to put the septic tank is just as important as determining the tank size that is needed. The septic tank should be placed where it can be easily accessed. For proper maintenance of the septic system, the tank should be pumped out every three to five years.
No outbuildings like sheds or decks should be built over the septic tank or drain field. Heavy items or driving over the septic tank or drain field can damage the system and cause early failure. Make sure the septic system design considers where driveways will need to be located.
Septic System Design And Drain Fields
The septic tank is only part of the septic system. The drain field is just as important as the tank. There are different types of drain fields available.
A conventional drain field is completely underground. It is a large rectangle area with pipes. The effluent from the septic tank flows through the pipes to be properly filtered by the soil. For this system, the correct soil conditions are needed. It should not be hard or compacted soil or too close to the groundwater.
Similar to a conventional drain field is a dry well drain field. This is completely underground. This system uses large pits filled with crushed rock or gravel instead of pipes and gravel.
When the soil around the septic system is not correct for the conventional drain field, a mound system can be used. With this system, a mound is built above ground level. The effluent from the septic tank is pumped to the mound, where it can then be filtered.
The Right Septic System Design Is Important
Make sure your septic system is designed correctly for the property. Following state regulations and proper installation keeps the environment and families safe. All Septic & Sewer installs, repairs, and pumps septic systems. Contact us today for more information, and follow us on Facebook.