sandy springs gateway corrugated metal pipe sand filters

Sandy Springs Gateway – 2015 Retention/Detention Project of the Year

By: Southeast Culvert

The Sandy Springs, Georgia Gateway project was originally designed with a large 144″ underground detention & multiple proprietary WQ units pre-treating the stormwater before it entered the detention system. During the permitting process, the city changed stormwater review engineers.

The new engineer did not give the proprietary units the removal efficiencies that his predecessor had.

As an alternative, Southeast Culvert proposed using Corrugated Metal Pipe (CMP) sand filters as the solution.  The Georgia Stormwater Manual recognizes sand filters as providing 80% TSS for stormwater.

SEC worked with the engineer to re-design the project to pre-treat the detentions using multiple 144″ CMP filters. The site was space limited so we had to use some pretty creative layouts. SEC was able to provide the filters, satisfying the City’s WQ concerns.

 Originally published May 29, 2015

For more information on this and the many other benefits of Corrugated Steel Pipe, contact us by calling (972) 850-1907 or visiting