Seawall drainage is a key element in having an effective seawall/bulkhead. The buildup of hydrostatic pressure on the land side of a wall is a major reason for failure. It is important to know that your seawall is not a dam, and its main purpose is to retain dirt. However, water should be allowed to pass in and out with the tides. Rainfall can be a key element to seawall failure and should be addressed accordingly. Proper grading in your backyard is very important. Downspouts to your gutters can dump behind your seawall causing settling or washout underneath your patios.
Wellpoint drains to the rescue!
Wellpoint drains can be installed on your existing or new seawall to alleviate pressure on your wall. A wellpoint drain is a pipe with openings large enough to allow water to enter and small enough to keep the water-bearing formation in place. Wellpoints are suitable for hand driving and are available in sizes from 1 1/4 to 2 inches in diameter and from 18 to 60 inches in length. The size openings in the drains is determined by the relative grain size of the material in the water-bearing formation. We typically install wellpoint drains as well as Jet Filter drains with replaceable cartridges.