Great Lakes Water Authority to Enhance Corrosion Control Measures to Provide Added Protection
- GLWA undertook a proactive, multi-year study in advance of changes in state and federal lead and copper regulations
- Levels of orthophosphate in GLWA’s treated water will increase to 2.4 milligrams per liter in a phased approach beginning in October 2024 (pending approval from EGLE)
- While there is no lead in GLWA’s water and no lead pipes are used in GLWA’s transmission system, upping the orthophosphate dosage will provide added protection for our member partners’ local systems
DETROIT— The Great Lakes Water Authority (GLWA) has announced it will increase the level of the anti-corrosion additive orthophosphate that it feeds into the water produced by its five water treatment plants in southeast Michigan. GLWA plans to slowly increase the dosage of orthophosphate from 1.2 milligrams per liter to 2.4 milligrams per liter between October 2024 and February 2025.
Orthophosphate acts as “water’s bodyguard,” forming a protective layer within pipes to prevent metals such as lead, iron and copper from dissolving in the water. GLWA has been adding orthophosphate into its water to control both corrosion and its effects on water quality since 1996. Since that time, optimal corrosion control has consistently been maintained in the water delivered by GLWA and monitored in accordance with EGLE regulatory requirements.
“While there is no lead in GLWA’s water and no lead pipes are used in the regional transmission system, upping the orthophosphate dosage will provide increased protections and assist our member partners in maintaining compliance with the changing lead action levels set by EGLE and updates to the U.S. Environmental Protection Agency’s Federal Lead and Copper Rule (LCR),” said Cheryl Porter, GLWA Chief Operating Officer-Water and Field Services.
Michigan’s action level for lead in drinking water is set to decrease from 15 parts per billion to 12 parts per billion on January 1, 2025. In 2027, a host of changes will also go into effect with the federal LCR, including a decrease in the time that municipalities have to remove lead service lines and a new trigger level for additional testing.
“GLWA’s processes and infrastructure must evolve alongside scientific advancements and technological improvements,” said Porter. “Proactive efforts like these enhanced corrosion control measures underscore our commitment to protecting public health and ensuring our region’s water quality remains of unquestionable quality.”
The change to GLWA’s corrosion control strategy was informed by a proactive, multi-year study conducted as part of its process of continual improvement and regulatory compliance.
As a part of the study, done in partnership with nationally known engineering firm Arcadis, specialty pipe loop rigs were constructed using pipes harvested from several local systems and installed at 10 testing sites – one for each of the five GLWA water treatment plants and five positioned at other locations within its member partner’s local distribution systems. Each member partner site represented a single water treatment plant’s water distribution service area. During the study, tests were performed using variable amounts of anti-corrosion chemicals to determine the most effective dosage recommendation.
Water will remain safe for consumption, as well as household and business use, while GLWA implements the changes to its corrosion control strategy.
Due to the increase in orthophosphate in the water treatment process, there will be an increase in the amount of phosphate that GLWA must remove during the wastewater treatment process. GLWA remains committed to ensuring that we continue to meet the federal and state regulators’ goal of reaching a 40 percent reduction in phosphorus. GLWA was the first treatment facility along the tributary to Lake Erie to achieve this milestone back in 2019.
About the Great Lakes Water Authority (GLWA)
The Great Lakes Water Authority (GLWA) is the provider-of-choice for drinking water services to nearly 40 percent, and efficient and effective wastewater services to nearly 30 percent, of Michigan’s population. With the Great Lakes as source water, GLWA is uniquely positioned to provide those it serves with water of unquestionable quality. GLWA also has the capacity to extend its services beyond its 88 member partner communities. As part of its commitment to water affordability, the Authority offers a Water Residential Assistance Program to assist low-income households in participating member communities throughout the system. GLWA’s board includes one representative each from Oakland, Macomb, and Wayne counties, two representatives from the city of Detroit, and one appointed by the Michigan governor to represent member partner communities outside of the tri-county area. For more information on GLWA and its role in ensuring millions of Michiganders have access to safe water, please visit glwater.org.
