When turning on a faucet, it’s expected that clear, fresh water should flow readily into a waiting glass, but, for many communities, this hasn’t always been the case.
To make sure the City of Madison’s water supply did not fall into being one of those communities, Madison Water Utility (MWU) began the East Side Water Supply (ESWS) Project in 2010 to study and recommend future infrastructure to improve the City’s water system. As part of the ESWS project, the Utility created Citizen’s Advisory Panels (CAP) to make sure new infrastructure met the expectations and desires of the community, and to facilitate communication during MWU projects. At the conclusion of the study in 2012, Well No. 7, on the north side of the city, was identified as an essential asset in the City’s water system and in need of an upgrade because of its age and water quality concerns about iron and manganese.
With assistance from Strand Associates, Inc.® and architectural design firm Potter Lawson, MWU set about reconstructing the well to improve water quality, restore the facility to full capacity, and blend into the well-established community aesthetics.
Well No. 7, located near the intersection of Sherman and Schlimgen Avenues, serves as an essential part of the City of Madison’s overall water supply system, providing water to more than 10,000 residents year round. The water produced contained elevated levels of manganese and iron that resulted in colored water events and customer complaints.
Originally constructed in 1939 as part of the Works Progress Administration (WPA) effort, Well No. 7 was state-of-the-art at the time with a 135,000-gallon reservoir and a facility capacity of 2,100 gallons per minute (gpm). The well house contained one booster pump, which along with the well pump discharge, was located below grade. This configuration posed a Department of Natural Resources (DNR) code problem as being below ground increased the potential for contamination, should the basement flood.
Another problem was the size of the well house. With one room housing electrical and chemical equipment, the well house needed a comprehensive update to meet current drinking water code standards and MWU policy standards for iron and manganese, as well as provide sufficient capacity for fire protection.
To mitigate the high levels of manganese and iron, the project team designed a high-rate pyrolusite filter system. Chlorine is introduced prior to filtration to serve both as an oxidant to remove the iron and manganese and also as a disinfectant. Chlorinated water is pumped to the pressure filter and the iron and manganese are adsorbed by the pyrolusite media. The pyrolusite media bed effectively removes all of the iron and manganese before the treated water is fluoridated and flows to the new 500,000-gallon reservoir. Two variable speed control booster pumps push the water out into the system providing redundant pumping capacity.
To remove the captured iron and manganese contaminants from the media, the filters are backwashed after producing 3 million gallons of water. Backwashing the tanks is essentially pumping treated water filters at a high rate. This causes the media bed to expand, which in turn flushes out the contaminants. Each backwash requires approximately 30,000 gallons of water. To conserve this water, the backwash waste is allowed to settle and the team designed a custom floating skimmer that “skims” off the water recycling it to the filters. More than 95 percent of the wash water is recycled as a result of this process. Only the iron and manganese “sludge” is discharged to the sanitary sewer system.
Along with the filtration system, the team installed a generator, separate chemical rooms, and more than tripled the size of the reservoir to bring the facility up to current design standards. The reservoir’s increased capacity now provides the City with the desired fire storage capacity it previously lacked.
The expanded reservoir, the filters, additional pumps, and the generator all resulted in a facility with a footprint nearly three times greater than the original structures. To accommodate the larger footprint and to provide reasonable setbacks, MWU obtained two adjacent land parcels
MWU worked closely with City Real Estate and the adjacent property owners to come to a fair and equitable settlement for the properties. MWU took extra care to make sure the transition and relocation of the property owners was smooth, efficient, and within their timeline.
Once the property was obtained, Madison Fire Department used the houses for training purposes and Habitat for Humanity salvaged building materials. MWU coordinated these efforts to make sure nothing was wasted and the public was involved throughout the entire process.
With the additional land and the well’s location on a corner lot with high street visibility, the community wanted to make sure the new facility blended in with the neighborhood and, remained loyal to the 1939 architecture. To address the community’s comments and given the size of the facility, the project team varied the heights of the facility, stepping them back from the street intersection to soften its visual impact.
The 1939 structure was constructed during the era of the New Deal as a Works Progress Administration (WPA) project and is the second oldest operating well in Madison. As such, MWU made sure to preserve the well’s history through a photographic record of the well house prior to its demolition. The project team incorporated stone from the original structure’s exterior into the new facility along with a plaque indicating the stone was from the original WPA well house. A wall panel composed of recycled exterior stone with the original WPA plaque was also incorporated into the interior of the well house to honor the historic nature of the 1939 structure.
Landscaping was employed to screen the well house from the neighboring residencies and to further blend into the suburban atmosphere.
To maintain the neighborhood’s personality and characteristics, the team went to great lengths to preserve a large maple tree on the corner of the site. The tree was identified as an important landmark to the community and, thus, the team took great care to preserve the maple by maintaining separation between the facility foundations, utilities, and the root structure. Special provisions were included in the construction documents that protected the maple tree not only from construction but also from the contractor’s activities.
The successful reconstruction of Well No.7 was completed with a strong collaboration with the community facilitated by the Citizen’s Advisory Panel. Using several CAP and public meetings and the resulting iterative project development, the group was able to reach consensus on the facility configuration and architecture. Clear communication coupled with innovative design made for a well-received finished product. With the finalization of Well 7’s reconstruction, Madison residents are now benefiting from improved water quality, pumping station reliability, and fire protection capacity.
“Madison Water Utility has received nothing but positive, glowing comments about the reconstructed Well 7,” said Al Larson, Principal Engineer at MWU. “The new structure has been described as the best looking water facility in the city….best of all, we have heard that the water tastes better. Through the hard work of the project team, Madison Water Utility now has a facility that will provide excellent service to the drinking water system for decades to come.”