Stormwater Infrastructure Design

THE PROJECT
The South Florida Water Management District (SFWMD) needed a divide structure within the stormwater treatment areas to increase the capacity of the flow, enabling the transfer of stormwater runoff for delivery for treatment or to the flow equalization basin (FEB) for storage and subsequent treatment.

Erdman Anthony was selected to design the plans and specifications for this project.

FEATURES/SOLUTIONS
The new divide spillway is a fully automated, three-gate structure, with a peak capacity of 2,600 cubic feet per second.  It is located along a levee in SFWMD’s Stormwater Treatment Area 1E, near West Palm Beach, Florida. The structure is located along the levee that separates the eastern and western distribution cells and allows SFWMD to manage and control water with bidirectional flow.

This project had five main elements: 

Remove the existing gated divide culverts
Replace them with a new gated divide spillway
Remove a portion of the existing levee due west of the new gated spillway to allow flow to enter the storage basin
Armor the north side of the canal at an easement
Provide an emergency generator for the new gated divide spillway that would also serve the existing structure approximately 1,000 feet to the south

IMPACTS
SFWMD can now manage water by storing it in the FEB during periods of heavy runoff and routing it to the stormwater treatment areas during dry periods. This allows SFWMD to:

• Treat more water rather than discharging excess runoff to tide
• Keep the stormwater treatment areas at a proper depth of water during the dry season, thus improving the water quality and helping to maintain the stormwater treatment areas

Erdman Anthony’s design was completed on time, which was critical because this project included a consent order to begin construction by a specified date. The project resulted in tight bids, with few change orders due to the quality of the plans and specifications prepared by our firm.

Sustainable Design Impact The divide spillway allows SFWMD to manage stormwater and makes it possible to treat more surface water for Everglade restoration.  During the wet season SFWMD will route surface waters to a reservoir where it will be stored until the dry season when the water treatment areas are able to accept additional water.  It also allows SFWMD to keep the water treatment areas healthier by providing water to them during the dry season when the plants are often stressed.  Once the water passes through the water treatment areas it is routed to the Everglades as clean, fresh water, to restore that unique ecosystem.