Waterloo Greenway and Waller Creek Corridor Restoration, Austin, Texas

The Challenge

Waller Creek is a highly urbanized stream in downtown Austin, Texas. The creek has experienced severe flooding, channel erosion, and degraded water quality. The frequent flooding within the creek has been controlled by the construction of a large tunnel that routes flood waters beneath downtown Austin and delivers excess flow to Lady Bird Lake. The Waller Creek Tunnel removes approximately 28 acres of downtown land from the 100-year floodplain, creating a new hydrologic condition for the creek and a unique opportunity for nature spaces and ecological restoration along the Waterloo Greenway Corridor.

In 2011, The Waller Creek Conservancy launched an international competition to redesign Waller Creek. LimnoTech was part of the winning design team led by MVVA. The design considerations outlined by the City’s Watershed Protection Department included the following:

• hydrological and ecological connectivity from Waterloo Park to Lady Bird Lake;
• a stable stream system design that provides sustainable form and function given a controlled flow regime;
• native riparian landscape that restores the natural and traditional character of a local stream;
• stormwater treatment opportunities;
• community outreach and educational opportunities; and
• flood safety and infrastructure protection.

The design concept had to address severe flooding, channel erosion, slope failures, invasive species, and degraded water quality that has been historically experienced in Waller Creek. Design concepts for the creek also needed to account for an existing plan to construct a large stormwater diversion tunnel (i.e., the Waller Creek Tunnel) that would convey most of the creek’s flows underground to the downstream Lady Bird Lake.

The Solution

LimnoTech’s primary role in this multi-phase project has been to evaluate the effects of a highly modified hydrology and design a new creek that provides appropriate morphology and aquatic habitat. Our work has included developing an in-depth understanding of the creek hydraulics and sediment dynamics. This understanding has facilitated our designs for riparian wetlands, pool/riffle sequences, aquatic organism passage structures, stormwater management features, community access opportunities, and countless habitat elements.

As the Waterlood Greenway and Waller Creek Corridor design has advanced, an essential part of the project has been working with the City, Conservancy, and regional planners to develop a shared understanding of the project objectives. Careful phasing of the project has allowed for different sections of the creek design to be sequenced and funded independently to allow the project to progress. Ultimately, we are working towards creating an urban ecology that provides a healthy and functional urban waterway, environmental benefits, and recreational opportunities for the people of Austin, Texas.