Dairy Fork Wetland and Habitat Restoration Project

This wetland project, which is part of the South Orange County Watershed Management Area plan, involved building a series of ponds and planting native, ecosystem-friendly plants. The goal was to naturally treat urban runoff draining from four south Orange County cities and significantly improve water quality in the area.

Project Facts
  • City of Aliso Viejo
  • Aliso Viejo, CA
  • Multi-jurisdictional wetland project
  • South Orange County Watershed Management Area Plan
  • ASCE and APWA Project Awards

The Challenge

Before, the project site was a disturbed grassland which was dominated by invasive exotic plants that offered no benefit to native flora and fauna. It also had an abandoned asphalt roadway that prevented infiltration of water from rain events which contributed to erosion and water quality. The proposed wetland would reduce pollutants in the water by as much as 99 percent. This multi-jurisdictional wetland project naturally treats urban runoff from about 1,500 acres of mixed residential and commercial areas within Aliso Viejo, Lake Forest, Laguna Hills and Laguna Woods before it merges with Aliso Creek.

The Solution

When groundwater testing and services were needed, HRS was able to provide the staff, equipment and resources needed to keep the project moving forward. HRS assisted the City with design changes to accommodate its budget while adhering to the project schedule. When a soil surplus accumulated beyond the amount in the grading plan, the initial thought was to move the soil off site, which would be costly. Instead, HRS worked with Dudek civil engineers to devise a plan to stockpile all soil on site, saving money. Over 10,000 native container plants were installed to create quality habitat for many species of fauna including California Gnatcatcher, Least Bell’s Vireo, and Southern Willow Flycatcher. The aquatic plants clean and filter the storm water as it meanders through the wetland pond systems before returning to the creek with its terminus at the Pacific Ocean.


Outstanding Environmental Engineering Project Award
by the American Society of Civil Engineers

2017 Project of the Year by the American Public Works Association

What We Do

Our restoration expertise provides the right staff and equipment to meet permit requirements.

Interested in what you’ve seen? Discover how we can help achieve your goal.