Percolation Tests

1. Provide a drawing (site plan) showing:

• Property lines
• Slope
• Proposed well location
• Proposed sewage disposal area (100′ x 100′)
• House and driveway location
• Existing wells and septic systems within 100 feet of property lines.

2. Prepare the following in the proposed sewage disposal area:

• One soil evaluation pit 3 ft. wide by 6 ft. deep sloped or stepped to the surface, in the center of the proposed sewage disposal area.
• Three percolation holes, 1 ft. in diameter and 2 ft. deep, spaced 50 feet apart, diagonally, on different contours.
• Provide 5 gallons of water beside each hole.
• Place a stake in the ground at each corner of the proposed sewage disposal area. An additional stake should be provided to locate the proposed well site.

When digging the six-foot pit one may encounter bedrock, fractured rock, or water table problems. Should this occur it may be possible to test in another location on the property. Therefore, it is recommended that the excavator and his backhoe be available the day of the tests. If a percolation rate between 2 and 30 minutes cannot be obtained additional percolation holes may be necessary. Therefore, digging equipment and additional water should also be available on test day. Should a different area be located for disposal of sewage from that which was originally proposed, the corner stakes can be moved to define the new area. When all tests have been satisfactorily completed, a final site plan will be prepared showing the approved sewage disposal area and the house, driveway, and well location. This approved site plan becomes a part of the sewage disposal permit that will be filed at the Health Department. A copy of the permit and site plan will be issued to the permittee. The sewage disposal system must be installed in the upper one-third of the approved sewage disposal area. This leaves two-thirds of the sewage disposal area for back up, in which repairs to, or replacement of the original system can be constructed. No construction, except sewage disposal, is permitted in the approved sewage disposal area.

Fees

Application fee for Percolation test $200.00

Final Inspection $75.00

TOTAL $275.00

A Plat Review Fee of $30.00 per lot may be required

Percolation fee must be paid in advance of test!

Typical Site Plan
(showing test hole locations)

Minimum setback distances for locating sewage disposal areas:

Property lines – 10 feet

Foundations – 10 feet

Steep Slopes (> 25%) – 25 feet

Drainage ways, gullies and spring seeps – 25 feet

Flood plain soils – 25 feet

Rock outcrops – 25 feet

Potable water wells – 100 feet

Stream not tributary to water supply reservoir – 100 feet

Water bodies not serving as potable water supplies – 100 feet

Stream tributary to water reservoir – 200 feet

Applications

Soil Evaluation Perc Test Application: https://garretthealth.org/wp-content/uploads/2023/01/Soil-Evaluation-Perc-Test-Application.pdf

Re-Evaluation Application: https://garretthealth.org/wp-content/uploads/2023/01/Percolation-Application-Re-Evaluation.pdf