With the implementation of new regulations from the State of Washington, most local counties (including Clark County) are now being forced to require an extensive review/permit process for any new or replacement “impervious” surface (driveway, roof, etc). Part of the process oftentimes requires a detailed soil description and infiltration test. If the timing is coordinated, EGSD can perform these tests at the same time as the testing for septic purposes. Although the tests are very different from each other, there are efficiencies in getting them completed at the same time.
For stormwater, the infiltration test involves placing a specific diameter pipe, a certain depth into the native soil at a prescribed depth from the surface. The pipe is filled with water (and re-filled as necessary) until the soil is saturated. After saturation, timed testing begins and the rate at which the water enters the soil is recorded. After multiple tests, the data is put into an equation and the “coefficient of permeability” is determined. The number is used in sizing stormwater infiltration systems.
Very knowledgeable engineers. I saved a ton of money and got a better system than what was previously recommended. Courteous folks to work with from the first phone call until completion. True professionals. Very highly recommended.