A rendering of what the gravel wetland will look like when it rains and when it doesn't

Water and Sewer

Walnut Creek Gravel Wetland

We are installing a gravel wetland at Walnut Creek Wetland Park. The wetland will include an underground gravel reservoir that'll hold and filter stormwater runoff. Plant roots in the wetland will soak up and clean the water. The gravel wetland also will slow down the flow of stormwater before it reaches Walnut Creek.

Project Details

 
Type:
Stormwater
Budget:
$350,000 (design & construction)
Project Lead:
Stormwater Management
Contractors:
Hazen and Sawyer (Design)

Contact

 

Heather Dutra
Senior Engineer
919-996-4012

Lead Department:
Engineering Services
Participating Department:
Parks, Recreation and Cultural Resources
Service Unit:
Stormwater

Subscribe

 

Planning

This phase is complete. 

Phase Contacts

 

Heather Dutra
Senior Engineer
919-996-4012

Lead Department:
Engineering Services

Design

This phase is complete.

Next Steps

 

 

Phase Contacts

 

Heather Dutra
Senior Engineer
919-996-4012

Lead Department:
Engineering Services

Construction

We have all the required permits for the project. We've started the construction bid process. This includes selecting a construction contractor. This will take a few months. Construction will start after we finalize the construction contract.

Phase Contacts

 

Heather Dutra
Senior Engineer
919-996-4012

Lead Department:
Engineering Services

Complete

Phase details coming soon. 

Phase Contacts

 

Heather Dutra
Senior Engineer
919-996-4012

Lead Department:
Engineering Services

A rendering of the plants, soil, pipes of the wetland on Peterson Street

A rendering of the Walnut Creek Gravel Wetland.

Schedule

Date Activity
Fall 2018 Project design began
Winter 2020 Project design complete
Spring 2020 Construction bid process
Fall 2020 Project construction begins
Summer 2021 Project construction complete

Background

The 5,300-square-foot wetland will capture stormwater runoff coming from Peterson Street and other nearby streets, sidewalks, and buildings (about one acre of impervious surface). Wetlands are a very effective way to treat stormwater runoff. The area is expected to prevent excess nitrogen and suspended solids from polluting waterways each year. 

  • 8 pounds of nitrogen 
  • 135 pounds of suspended solids

This is a great example of how planted stormwater devices help the environment. The features remove pollution and reduce impacts to stormwater pipes and streams.

Learn more about green stormwater infrastructure