2022 Project of the Year Winner – Polymer Coating: Cache Creek Tube Phase 2

By: TrueNorth Steel

 

Hydrodynamic Separator Storm Drain System

Jackson, WY is a town located in the Jackson Hole Valley, just south of Grand Teton National Park. Cache Creek flows through Jackson and originates in the Bridger National Forest in a Wilderness area. Cache Creek runs through 3 storm drain pipes below the town, some of which is located on private property and reemerges for final discharge into flat creek. As these creeks disappear via subterranean flows, a way to keep the community connected with the creek is to use a newer technique called “Daylighting” and ground stenciling. The route the creek flows through town. Daylighting is the process of resurfacing the flow back to a natural stream bed.

Hydrodynamic Separator Storm Drain System

As part of an infrastructure project to consolidate the storm drain system underneath one right away, a treatment system was needed to improve the water quality and remove sediment, floatable debris and oil from the storm drain system and can target particle sizes as small as 50 microns. (For context, the diameter of a human hair is ~100 microns.) An AS-10 Hydrodynamic Separator (HDS) was selected as the solution to mitigate pollutants for final discharge into Flat Creek.

Hydrodynamic Separator Storm Drain System

TrueNorth Steel manufactured the Polymeric Coated AS-10 Hydrodynamic Separator. The materials consist of 10ft diameter x 12ga 5×1 Polymeric coated steel and 12 ft vertical height. The inlet and outlet pipe are 30in Diameter x 16ga 2 2/3 x ½ Polymeric Coated Steel. The poly HDS system can treat water quality flows up to 17.5 cfs and is equipped with its own internal bypass to bypass high rain intensity events.

Traditional HDS system are typically manufactured using concrete manholes, which makes this type of system unique.

Hydrodynamic Separator Storm Drain System

 

For more information visit the Teton Conservation website here.