Kim Norvell

knorvell@dmreg.com

West Des Moines and Waukee will explore building a water treatment facility to serve the growing suburbs and potentially alleviate the cities' dependence on Des Moines Water Works.

The first step is finding out whether the Raccoon River alluvial aquifer along the southern edge of West Des Moines has enough water capacity to serve the cities' needs.

Officials from West Des Moines and Waukee met separately Tuesday night to approve a $84,100 study of the water supply. If it finds there is enough water in the aquifer to support the cities' growing needs, they will explore the costs of building a water treatment facility.

West Des Moines Water Works already operates a water treatment facility at 1505 Railroad Ave. It can produce up to 12 million gallons a day, but it also purchases water from Des Moines Water Works. It has the option to buy up to 9 million gallons of water a day from the Des Moines facility. Waukee relies solely on Des Moines Water Works for its clean water supply.

Both cities' water needs are expected to increase dramatically in the next 20 to 25 years. Waukee's needs are expected to triple by 2035. West Des Moines' water need could rise 1½ times by 2040.

Des Moines Water Works CEO Bill Stowe said he doubts the alluvial aquifer will be sufficient to meet the cities' needs. He also questions the logic of moving away from a regional approach to water treatment.

"If the study turns into moving forward with splitting water production, that would be a huge concern for us," Stowe said. "But realistically I would find that highly unlikely."

An alluvial aquifer like the Raccoon River's stores water in the sand, gravel, silt or clay that surrounds a river. The ground water replenishes slower than surface water.

Des Moines Water Works provides clean water to roughly 500,000 customers and sells wholesale to more than 20 regional entities. Its board approved a 10 percent across-the-board rate hike this year that impacted all individual ratepayers and wholesale customers — including the cities of West Des Moines and Waukee.

A new $2.5 billion Microsoft data center is expected to open up thousands of acres to new development in southwest West Des Moines, while the new Grand Prairie Parkway interchange will open access to a technology corridor on the city's northern border with Waukee. Residential development in Waukee is expected to push west of Ute Avenue, while new businesses look to infill areas along Hickman Road and developers announce plans for Kettlestone, a 1,500-acre development north of the new interstate interchange.

The latest Microsoft data center is the third project the company plans to build in West Des Moines. Data centers use massive amounts of water, especially on hot days, to run cooling systems for computer servers. Just one data center could use 2.4 million to 6 million gallons of water a day when temperatures reach 90 degree or higher. On an average day the data center would use less than 1 million gallons.

Last year, West Des Moines Water Works commissioned a study that recommended exploring different sources of water and treatment options. The study found that in two years, West Des Moines' demand for water would meet its current production limits, according to General Manager Diana Wilson.

The independent utility treats water pulled from 22 wells to serve residential, commercial and industrial customers in West Des Moines. It also purchases roughly 30 percent of its annual water supply from Des Moines Water Works, Wilson said.

West Des Moines uses an average of 7.2 million gallons of water a day, but it can use up to 16.1 million gallons on peak summer days when residents are watering their lawns or filling pools, Wilson said. By 2040, the city's water use is expected to be 11.5 million gallons a day, with 25.1 million gallons on peak days, the study found.

Waukee uses an average of 1.1 million gallons of water a day, with peak days reaching 3.1 million gallons. That could increase to 10.2 million gallons of water a day by 2035, according to data from the city.

"West Des Moines and Waukee have a lot of common interests. (And) the thought was that with these common interests, maybe we can address the water issue together," Waukee City Administrator Tim Moerman said. "So this is the first step in getting good information to make a good decision."

Together the suburbs are allotted 12.5 million gallons of water a day from Des Moines Water Works without penalty. Any increases to daily allotments — for any wholesale customer — would require a costly expansion of Des Moines Water Works' treatment facilities, Stowe said.

The utility is in the middle of its own study of metrowide water needs. Results outlining construction costs for different facility expansion scenarios are expected in mid-2017. Stowe said he is confident immediate needs in West Des Moines and Waukee could be met with Des Moines Water Works' three treatment facilities.

"For those future needs that aren’t met, the solution is more regional production," not localized treatment plants, he said. Water production can have various highs and lows depending on weather and demand, and keeping the utility regional would ensure steady rates, he said.

"The idea of having a number of different local communities producing their water is going to be a detriment to customers because it will drive up costs for everyone and it will discourage economic development in those communities," Stowe said.

West Des Moines and Waukee use roughly 20 percent of the clean water produced by Des Moines Water Works. It's predicted the cities will use 40 percent of the utility's water production within 25 years.

"They’re a really important part of our customer base," Stowe said.

Moerman said Waukee and West Des Moines Water Works don't have "any preconceived notion" about which option would better meet the suburbs' needs in the future. The joint study will provide options to make an informed decision, he said.

"This isn’t an effort to leave Des Moines behind," Wilson said. "This is really an effort to increase the number of options so we are making the best possible decisions for our rate payers."

"At this point, I don’t foresee not being partners with Des Moines. There's certain points of our system that just lend themselves to being served by Des Moines Water Works."

Des Moines supplies water to the northwest corner of West Des Moines and areas south of the Raccoon River. It also supplies water to Microsoft's facility that's under construction in the southeast corner of West Des Moines, and it plans to help supply water to the software giant's newly announced data center seven miles west. Plans are still in the works for exactly how water will be delivered to the new facility, Wilson said.

Results of the joint water quantity study, conducted by Veenstra & Kimm Inc., are expected by Jan. 31. Engineers will study at least three sites along the Raccoon River from Interstate 35 west to Van Meter.

If it's determined the Raccoon River alluvial aquifer has enough water, the two entities would direct Veenstra & Kimm to conduct test pumping and apply for a water allocation permit from the Iowa Department of Natural Resources.

Urbandale explores building its own water treatment facility

As West Des Moines and Waukee launch a study of the Raccoon River alluvial aquifer, the Urbandale Water Utility Board of Trustees is looking at the possibility of constructing its own water treatment plant.

Urbandale purchases all of its water from Des Moines Water Works. But rising costs coming from the utility and concerns about Des Moines' ability to meet the needs of its regional customers has the Urbandale utility board looking at alternatives.

“Is it less expensive to purchase water from Des Moines, or will it be less expensive to build a facility and provide Urbandale water to its customers through its own facility?” Urbandale Mayor Bob Andeweg said.

While the specific numbers are unknown, the plant could cost around $60 million, said Dale Acheson, Urbandale water utility general manager. The Urbandale utility is separate from the city. It does not have to seek voter approval to issue bonds or obtain City Council backing. The organization is funded by water rates.

Urbandale officials have been discussing the idea of building a water treatment plant since 2010, Acheson said. In 2012, the Urbandale water utility purchased two former gravel pits east of Beaver Drive in Johnston. The 110 acres of land cost $870,000.

The pits are located near the Des Moines River and could serve as a water source for a water treatment facility. The plant could be built west of Merle Hay Road along Interstate Highway 35-80, where the utility owns 30 acres of land.

So far, Urbandale is just considering its options, Acheson said. If a plant were constructed, it could be done in partnership with Des Moines Water Works.

An engineering company is conducting a design study to determine how much the project would cost. It’s expected to finish in the next six to 12 months, Acheson said.