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

Stormwater

Walnut Creek Gravel Wetland

Green Stormwater Infrastructure

We installed a gravel wetland at Walnut Creek Wetland Park. The wetland includes:

  • An underground gravel reservoir that'll hold and filter stormwater runoff;
  • Plant roots that will soak up and clean the water; and, 
  • Slowing down the flow of stormwater before it reaches Walnut Creek.

This project was partly funded by a grant from the NC Department of Environmental Quality. The grant covered some construction costs and educational art at the gravel wetland. 

Project Details

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

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

This phase is complete. 

Phase Contacts

 

Heather Dutra
Senior Engineer
919-996-4012

Lead Department:
Engineering Services

Complete

Crews finished this green stormwater infrastructure project in October. Work for the gravel wetland included: 

  • Installing the pipes and drainage system; 
  • Excavating the area; 
  • Adding gravel to the wetland; and, 
  • Seeding and adding a fence to the area. 

During the warranty period, crews will make required repairs or maintenance for the project. This period ends in fall 2022. 

Creative Educational Installation

There will be an interactive installation on site to educate the community about this project. Learn more

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 - Fall 2020 Construction bid process
Winter 2021 Project construction phase begins
Fall 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