Herriman and Riverton residents will have a new way to water their lawns this spring — and one more place to go fishing.

When it is completed, the Blackridge Reservoir — a seven-acre secondary irrigation pond being built by Herriman and Riverton in the Rosecrest area of Herriman — will supply Herriman's new secondary irrigation system and bolster Riverton's water pressure. With a sandy beach, freshly stocked fish and an open invitation to go swimming, the reservoir also is expected to become an aquatic oasis on the west bench.

"We're pretty excited about it," said John Stillman, water department director for Herriman. "To be able to provide secondary, outdoor water use will be great. It's pretty expensive to throw (culinary water) out on the grass. Utah is one of the second-driest states, and we're one of the heaviest water users. It's hard to keep a desert green."

The pond, named for its proximity to a ridge of lava rock in the area, will provide water to about 56 percent of Herriman, Stillman said, though piping for the reservoir doesn't yet run throughout the city. Herriman has a plan to get the entire city on secondary water within 10 years, Stillman said.

The cities plan to build a sandy beach around the water's edge and keep the reservoir stocked with bass, catfish and rainbow trout. Swimming and paddle boating will be allowed, but motorized boats will be prohibited.

Water from Utah Lake will flow to the Welby Jacob Canal, then into the Blackridge Reservoir during the day and out onto residents' lawns at night. Both Riverton and Herriman have chipped in $3.5 million per city to pay for the reservoir's pipeline and easements, but the reservoir is being built in Herriman because it's at a higher elevation.

Riverton approached Herriman with the idea for the project about two years ago because Riverton has been having problems with water pressure in some areas of the city. Some residents have been having problems watering their yards, said Riverton water director Scott Hill.

Riverton already has secondary irrigation plumbing throughout the city, but the added water source will help complete the areas that currently have weak pressure.

"This is the icing on the cake for Riverton," Hill said. "We've been doing this since 1999, and this is the last hard portion to make us 100 percent."

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