Partnering to Deliver the Nation’s Largest Progressive Design‐Build Water Treatment Plant Project
The City of Houston (City) is expanding its Northeast Water Purification Plant (NEWPP) from 80 million gallons per day (mgd) to 400 mgd, increasing its ability to support steady residential and commercial growth while complying with a regional mandate to reduce dependency on groundwater. The Houston Waterworks Team (HWT), a joint venture between CDM Smith and Jacobs, is delivering this $1.8 billion, nine‐year, project in partnership with the City and its four regional water authority partners. The NEWPP Expansion project is the largest progressive design‐build project of its kind presently underway in the U.S.
The raw water from Lake Houston is challenging to treat because its characteristics vary widely due to the Lake’s multiple tributaries and its relatively small volume. During rain events, raw water turbidity and TOC levels can easily top 250 NTU and 20 mg/L, respectively, while alkalinity levels drop below 10 mg/L. To handle this variability, HWT’s design includes a robust pH and alkalinity adjustment process which will support two primary coagulation processes. The project also includes Houston’s first use of ozone for primary disinfection and taste and odor control, and chlorine dioxide for mussel mitigation and manganese precipitation.
As the City’s largest water treatment plant, redundancy, reliability, and resiliency served as key criteria for the project’s design, especially in consideration of its hurricane prone location. Such criteria provided the guiding principles for each of the project’s 200+ design workshops.
- Discuss what is the most important mind‐set of a team member on a progressive design‐build project.
- Learn the three major purposes of ozone on the project.
- Identify what major characteristics made the raw water on the project difficult to treat.