The development of the new Pulte Homes Potomac Yard condominium complex in Alexandria, Va., required the removal of phosphorus and the treatment of a water quality volume of 53,161 cu ft for total suspended solids.
Phosphorus removal was required to meet or exceed 60% removal and is being accomplished in multiple locations. As part of the system, detention of storm water is also required.
The original design required multiple sand filter beds throughout the project to meet the required treatment rates. The goal of the project was to create a more sustainable solution with decreased start-up costs. A secondary goal was to provide a system that was easier to maintain and would provide a longer life-cycle. The technology was selected because it provided significant cost savings over traditional sand filters while performing at a greater or equal performance.
The project faced several significant challenges. The city had requirements that only natural treatment methods could be used, which created regulatory concerns. Although the project created a significant volume of runoff and water quality storm event volume, the site is split into many drainage basins, creating issues in the construction of treatment facilities. The increased phosphorus removal requirement meant that a higher level of treatment was required.
The Bayfilter system addressed all the concerns of the property owner as well as the regulatory agencies to provide a complete, easy-to-maintain water treatment option.