Martinez IV Wastewater Treatment Plant
San Antonio River Authority’s Martinez IV Wastewater Treatment Plant Earns Envision Silver
September 9, 2019 – The Institute for Sustainable Infrastructure (ISI) announced today that the Martinez IV Wastewater Treatment Plant in Saint Hedwig, Texas is the recent recipient of the Envision Silver award for sustainable infrastructure.
The Martinez IV Wastewater Treatment Plant (WWTP) is a new facility built to accommodate the significant projected population growth of the surrounding communities. Without this facility, the increased raw sewage would need to be pumped and hauled by truck on a daily basis to other facilities for treatment, causing significant impacts to soil, watershed quality, air pollution, and carbon dioxide emissions.
Operated by the San Antonio River Authority (River Authority), the plant has a treatment capacity of 250,000 gallons per day (GPD) with potential to expand to two million gallons per day (MGD). The project consists of headworks, biological treatment, clarifiers, ultraviolet (UV) disinfection, and dewatering with final solids being composted. In addition, a new sanitary sewer collection line and associated lift station will connect new residential developments to the wastewater treatment plant. The collection line will consist of approximately 17,000 linear feet of gravity and force main and one lift station.
The Martinez IV WWTP project helps to fulfill the River Authority’s strategic planning goals, including generating lasting and recognized improvements to the health and safety of the area’s creeks, rivers, bays, and estuaries; and to expand, diversify, and leverage funding sources and partnerships by delivering lasting results for the community.
The River Authority worked in close collaboration with Freese and Nichols and MGC Contractors to deliver this award-winning sustainable project.
“ISI is pleased to issue a Silver award for sustainable infrastructure to the San Antonio River Authority for the Martinez IV Wastewater Treatment Plant,” said Melissa Peneycad, ISI’s Managing Director. “The project underwent a rigorous and comprehensive third-party verification process against the Envision framework. As a result, ISI is pleased to confirm this project delivers a range of environmental, social, and economic benefits to the communities it serves”.
“The San Antonio River Authority is committed to safe, clean, and enjoyable creeks and rivers, so the decision to provide the community with sustainable infrastructure and pursue an Envision rating for the Martinez IV Project is in line with our vision and mission,” said Amy Middleton, San Antonio River Authority Utilities Manager and Martinez IV Project Manager. “The project was successful due to the synergy experienced between MGC Contractors, Freese and Nichols, and the River Authority. Without all three passionate participants, this award would not have been achievable”.
The Envision system examines the impact of sustainable infrastructure projects as a whole, through five distinct categories: Quality of Life, Leadership, Resource Allocation, Natural World, and Climate and Resilience. These key areas contribute to the positive social, economic, and environmental impacts on a community.
Some of the project features that led to the Martinez IV WWTP earning an Envision Silver award include:
Onsite renewable solar energy will provide 41.5% of energy usage for process equipment. In addition, all soil excavated during construction was retained on site and stored according to their original function. This allowed the placement of soil according to its natural soil horizon, including a berm built around the perimeter of the site, which improved the drainage pattern of the site. Non-potable water produced by the treatment system is used throughout the site for irrigation and cleaning. Lastly, the vast majority of waste from the plant and the office are recyclable materials, minimizing the treatment plants impact to landfills.
Invasive species were removed from the site and it was re-vegetated with several native species, including milkweed to serve as habitat for monarch butterflies migrating through the area. Low Impact Development was used to treat stormwater runoff from the roadways and treatment plant. In addition, sustainable materials in the office and LED lighting was used throughout the project site, while being mindful of the direction of lighting to protect the night sky.
Climate and Resilience
The plant was designed with long-term climate considerations in mind. While current regulations require the plant to be situated outside of the 100-year floodplain, the plant was positioned beyond the 500-year floodplain to reduce risks from flooding. In the event of severe drought, the plant can be retrofitted for water reuse of plant effluent for community irrigation purposes.