McCarrons Water Treatment Plant Improvements Project

Front of McCarrons Treatment Plant

The entrance to the McCarrons water treatment plant. The building pictured here will remain  in service after the upgrades to the plant are complete.

In January, 2021, SPRWS began an exciting project aimed at upgrading the McCarron’s Water Treatment Plant.

Since the mid-1910s, the McCarrons Water Treatment Plant has been providing reliable, quality drinking water to residents of Saint Paul and neighboring communities. 
Though the facility has been expanded on several occasions, much of the infrastructure which supplies our customers with water is nearing 100-years in age. 

Despite its age, the treatment plant continues to perform well and produce high quality drinking water for 450,000 people in St. Paul and the surrounding communities.  In fact, the McCarrons water treatment plant is one of only 31 facilities in the nation to have received the Presidents’ Award for Water Treatment from the Partnership for Safe Water. Our staff is proud of the role that our exceptional water quality plays in maintaining public health.

While current water quality remains exceptional, SPRWS is proactively looking towards the future and planning to make significant improvements to the McCarrons water treatment plant. These improvements will position SPRWS to continue providing high quality water far into the future.

Most of the changes to the facility will be targeted at improving reliability and flexibility and will enable the utility to continue to meet the needs of customers in the future. The utility has a longstanding history of proactively investing in infrastructure. Those investments have made the utility one of nation’s best, and modern investments build on that tradition. 

Overall, SPRWS expects to replace roughly 2/3rds of the existing treatment process with more modern technology.  We are also considering the potential addition of ozonation, a treatment process which may offer significant benefits for our customers.

While this project is still in its early stages, a significant milestone was reached when SPRWS signed a contract with Jacobs Engineering to perform the design and construction services for the project.


What is the project budget?

Preliminary estimates for the project suggest that the budget for the project will be approximately $160M.  This number will be refined over the course of 2021 as design of the facility progresses.

Why invest now?

Investing in water infrastructure before it fails is absolutely vital.  Nearly half a million people depend on the McCarron’s Water Treatment Plant every single day.  Waiting for the facility to begin failing is not an option because of the vital role it plays in sustaining public health and livelihood.

Additionally, low interest rates make this an attractive time to finance the project, and we look forward to the opportunity to improve the reliability of the facility and to increase the future flexibility of the site.

Ultimately, the foresight of our predecessors has allowed us to depend on this facility for a century.  A similar level of foresight is needed today in order to secure the future of drinking water for our customers in the coming generations.

Will the taste of the water change?

Taste changes are unlikely to be noticeable.  Extensive preliminary testing will help to ensure that the project does not result in any adverse impacts to water quality.

Will water rates change?

Early projections suggest that the average SPRWS customer will experience a rate increase of roughly $6 per month between 2021 and 2024.  This estimate is based on very preliminary data and will be further refined as design progresses.

SPRWS takes seriously its responsibility to invest wisely on behalf of its customers and will thoroughly consider costs and benefits when making all project decisions.

Will there be impacts to water service?

We do not expect any plant shutdowns or interruptions to water service during the project.

What is the project timeline?

Design work began in January of 2021 and is expected to continue until summer of 2022.  Some site preparation demolition and grading may begin in the spring of 2022.  The bulk of the construction and demolition efforts are expected to take place between fall of 2022 and 2025.

What steps are you taking to ensure that there are no negative impacts on the water?

SPRWS will partner with Jacobs Engineering, the University of Minnesota, and the Minnesota Department of Health to run a small-scale water treatment facility on site for 12 months.  The small-scale facility will utilize all of the new treatment processes proposed and will provide ample opportunity to spot any concerns well before any construction takes place.

Additionally, the existing facility will remain operational throughout the project.  SPRWS will continue to operate with the existing facility until the new facility has passed rigorous inspection and water quality tests.

What will happen to the existing facility?

Front of the McCarrons Treatment Plant











 The portion of McCarrons Water Treatment Plant seen here will remain in service after the project to upgrade the facility is complete.

SPRWS expects that several existing structures, largely those underground, will be demolished once the project is complete.  SPRWS is collaborating with the State Historic Preservation Office to document the history of the facility.  Additionally, SPRWS staff has undertaken several historical documentation efforts to ensure that the history of the facility will be honored.

Demolition of existing structures will be necessary in order to limit facility maintenance costs, to make room for new components, and to open up free space on the site for any future additions that may be necessary.

Where can I learn more?

SPRWS staff will provide updates on this webpage as the project progresses. 


Last Edited: March 1, 2021