Bill Murphy, P.E.Specifications Engineer, Quick Supply/ASP Enterprises

Recent Posts

FocalPoint HPMBS: Mulch Matters

Posted by Bill Murphy, P.E.Specifications Engineer, Quick Supply/ASP Enterprises on Tue, Jun 02, 2015 @ 08:25 AM

When introducing FocalPoint HPMBS to engineers, landscape architects, public agencies and contractors, we sometimes get asked if the mulch layer is really necessary. Some people want to replace it with various sizes and types of rocks while others contemplate eliminating the top layer altogether. We continue to stress the importance of the mulch as an important part of any bioretention system. Recently we inspected a FocalPoint that was installed last fall and found that the mulch layer worked exactly as designed (see pictures below). Although the area immediately surrounding this FocalPoint was stabilized before commissioning the system, there was still a tremendous amount of sediment carried into this basin during the spring months. During our site visit we discovered an area on the site that had been disturbed as part of an unrelated landscape project and not been properly protected. Silt and undesirable mulch from that site was washed into the storm sewer and deposited into this FocalPoint basin. Here are three lessons learned from this inspection:

Read More

Tags: Low Impact Development, Green Infrastructure, Water Quality, Bioretention Design, Biofiltration Systems