Septic Design Q&A | Horizon Wastewater

SEPTIC SYSTEM Q&A________

Q: WHAT TYPE OF SEPTIC SYSTEM DO I NEED? A: The answer to that will depend on a number of factors. The largest driving factors behind system-type, are the soil conditions. Since the sewage is going to eventually be disposed of in the soil, we need to find out how well the soil is suited to accept it. If the soil conditions are optimal, we can let it do a lot of the work in treating and disposing. However If the soil conditions aren't great, we may need to reduce the "strength" of the sewage before it goes into the soil. This is accomplished in many different ways. Some are complex, some are very simple. But every project is different, and the exact site and soil conditions will help determine what options are available to us.

Q: WHAT IS A FEASIBILITY STUDY OR "PERC-TEST"? A: A Feasibility Study is a site visit to evaluate the site and soil conditions with regard to septic system design & installation. A soil test-pit (or multiple) is excavated, and the site features are investigated. Sometimes a letter is generated by the designer explaining the findings, along with any recommendations. The term "Perc-Test" describes the process by which soil infiltration and loading-rates can be determined. A small test pit is excavated, and water is poured into the pit. The elapsed time that passes while the water is infiltrating into the soil is then recorded. Generally speaking, this process has not been practiced in this area for many, many years. In modern times the designer is equipped with knowledge of soil characteristics, and reference materials to more accurately determine the soil's ability to accept sewage. This includes visual and tactile inspection of the soil profile as a whole. Occasionally further testing may be necessary.

Q: DO I NEED A FEASIBILITY STUDY, OR DO I NEED A DESIGN? A: If you are looking to purchase a property, and are unsure if a septic system might be supported on it, then a Feasibility Study may be helpful to you. Feasibility Studies are not generally reviewed by a Health Jurisdiction, and are for informational purposes only. If you want to know that the health district will APPROVE a septic system on the property, a septic design is necessary. If you want a design performed on a project, you do not also need a Feasibility Study. The data gathered during a septic system design is more comprehensive than a feasilbility study.

Q: WHAT IS A "GRAVITY" SEPTIC SYSTEM? A: "Gravity" system refers to how the sewage is dispersed into the soil. Typically, sewage flows from a building into a septic tank, then from the septic tank into a distribution box in the drain field. However, a gravity drain field does not necessarily need to be "downhill" of a house or building. A small pump can carry the sewage to the distribution box, where gravity then takes over and disperses the sewage into the soil.

Q: IS A GRAVITY SYSTEM THE BEST TYPE OF SYSTEM? A: A gravity system is typically the most economical type of system to install and maintain. This feature alone makes it desirable. However as with many other things, there are benefits and drawbacks. Gravity systems have very little flexibility in terms of installation location and configuration. They require the deepest usable soil profile than nearly all other systems. They also don't meet a high treament standard. So on projects that have limited available real estate and/or other critical area concerns (wetlands, shoreline, buffers, etc,) gravity systems may not be well-suited, or even feasible. Thankfully, there are many other options available if your project cannot support a gravity septic system.

Q: HOW MUCH WILL IT COST FOR A SEPTIC SYSTEM DESIGN? A: Design fees will vary slightly, depending on the project's complexity. But typically after asking a few questions and doing a little research, we can give you a quote right over the phone.

Q: DOES HORIZON WASTEWATER ALSO CONSTRUCT THE SEPTIC SYSTEM? A: No. We can however recommend installation contractors that, in our experience, are exemplary.

Q: CAN YOU DESIGN A SEPTIC SYSTEM ON A SMALL LOT? A: Probably! We enjoy a challenge, and restricted properties give us the opportunity to find a creative solution. It's rare (though possible) for a property to be deemed "un-buildable".