Assessing Soil Water Drainage - Ask Vinny

Dear Perc,

A percolation or "perc" test measures how quickly water drains into the ground. It's performed to determine the soil's ability to absorb water and handle sewage wastewater and is required for many reasons, including designing septic systems. The perc test results determine what size leach field is needed for a new septic system. To perform a perc test, a professional inspector digs holes around the proposed septic system area and measures how long it takes for water to drain into the ground.

A perc test is required in many areas before a septic permit is issued. Some counties have specific requirements for who can conduct a perc test, so it's best to contact your local health or planning department for more information.