The project is a major addition being built onto the John W. Pray Water Facility on Phinney Park Drive. That addition will house reverse osmosis equipment that will reduce the hardness of the city’s drinking water.

Since the project was first publicly discussed in 2017, engineers have said the reverse osmosis equipment will not produce true soft water. However, according to the engineers, it will reduce the hardness of the water so significantly that water softeners won’t have to work as hard. For homeowners, that means fewer bags of salt to buy, lift and dump into the softener.

The hardness of water is measured in grains, with zero grains being soft water. Fort Dodge water has been measured at about 26 grains of hardness in the past. The new system is expected to reduce that level to about seven grains.

”What this does is give us improved drinking water to the community as a whole,” City Engineer Tony Trotter said.

He explained that in the reverse osmosis process, water is pumped through plastic membranes filled with microscopic holes that only water molecules can pass through.

Crews from Woodruff Construction, of Fort Dodge, started building the addition last spring. The structure is now up and fully enclosed.

”They’re moving right along,” Trotter said.

He said the project is to be done by November.

Woodruff Construction has a $19,970,000 contract.

The reverse osmosis equipment was purchased from Harn RO Systems Inc., of Venice, Florida, for $3,343,500.

Paying for all of that has added about $7 a month to residential water bills.

The project was prompted by new restrictions the state Department of Natural Resources has imposed on the amount of chloride in treated water discharged from the wastewater treatment plant into the Des Moines River. There is no cost effective way to get rid of the chlorides at the wastewater treatment plant. Therefore, they have to be removed at the source. In Fort Dodge, water softeners are the source of about 70 percent of the chlorides.

By reducing the hardness of the water before it leaves the John W. Pray Water Facility, engineers hope to reduce the workload of those softeners and thus curtail the amount of chlorides going to the wastewater treatment plant.