Maximizing Stormwater Management with CSP Sand Filters

By: Lane Enterprises, LLC

Development Boom Brings Stormwater Challenges

Princedale Apartments is part of a growing trend of apartment complexes. These complexes are appearing everywhere. Located in Prince William County, this development faces traffic congestion. Northern Virginia also has high housing demand. Consequently, the site presented challenges for stormwater management. For example, there were two drainage areas. These areas flowed into a wetland. This wetland had a stream. Therefore, the site needed two stormwater management systems capable of incorporating CSP Sand Filters. These systems needed to address storage and water quality.

Space-Saving Superstars: CSP Sand Filters Take the Stage

To tackle the stormwater challenge, the engineer and owner opted for a clever solution. They chose two CSP sand filters, each boasting a massive 120-inch diameter. But here’s the kicker: each filter also has a secret weapon—a separate storage compartment. This compartment acts like a hidden reservoir, providing extra storage specifically for the 10-year storm. This ingenious combination of filtration and storage not only saves space but also efficiently meets the overall storage requirement.

Sand Filters: The Unsung Heroes of Water Quality

The Virginia DEQ has a tough job. They need to ensure clean water for everyone. Thankfully, they have a powerful tool: sand filters. These filters are the most efficient way to reduce phosphorus. In the past, building sand filters was a costly endeavor. They required long concrete vaults. But now, things are different. With CSP sand filters, we can use large diameter pipes instead. This innovative approach is much more economical, making it a win-win for both budgets and the environment.

Thinking Outside the (84-inch) Pipe

The engineer had prior experience with CSP sand filter systems. Therefore, he chose this approach for this project. Typically, CSP sand filters are designed with 84-inch diameter pipe. However, space was limited at Princedale. As a result, they decided to use 120-inch pipe. By utilizing perforated pipe for storage, they increased storage capacity. Moreover, bypasses were included in the design of these CSP Sand Filters. These bypasses allow larger storms to go directly to the storage area.