A new 54-acre wetlands area in the City of Boise, Idaho, offers community members a natural environment with a walking path and recreational park. A collaborative effort among the Boise department of public works, Ada County Highway District (ACHD) and the Settlers Irrigation District (SID) made the Hyatt Hidden Lakes Reserve project possible.
“Everybody got something they needed,” says Bruce Mills, ACHD deputy director. “I think the community is really going to like the park.”
In 2008, the City of Boise received a $1 million grant from the U.S. EPA to create an innovative stormwater demonstration project at the site donated by businessman Larry Hyatt.
An irrigation canal operated by Settlers Irrigation District (SID) runs along the south side of the Hyatt Wetlands. Before the wetlands was created, ACHD was working with SID to design an area for stormwater runoff. SID could not handle the excess water at its downstream facilities and said it needed the ability to release or store up to 40 acre-feet of irrigation flows from the canal.
Mills worked with the City of Boise to build out the area that had previously been used as farmland. “It used to be farm ground, then they started a gravel pit,” says Jim Wyllie, Boise civil engineer and the wetlands project manager. “They excavated the gravel down to the point where they couldn’t keep it dewatered anymore so they just walked away. Then beavers created dams around it and the area turned into wetlands.”
The location offered 22 acres of wetlands, but ACHD needed more acreage to store the necessary volume of stormwater designated by SID. “The highway district constructed six new acres of wetlands on a 10-acre parcel contiguous to the site to provide the additional storage,” says Wyllie.
The project also includes a stormwater filter that treats runoff. “We’re cleaning the water before it gets into the wetlands,” says Wyllie. “It gives us an opportunity, given the size of the facility, to treat quite a bit of runoff that formerly used to be dumped in Settlers’ canal.” The treated stormwater is then discharged to the Thurman Mill Drain before reaching the Boise River.
In the end, each of the parties was able to agree that a newly established wetlands area would be beneficial for all involved.
SID can now discharge up to 40 acre-feet of irrigation flows into the Hyatt Reserve and alleviate flooding of its downstream facilities. The City of Boise completed the stormwater demonstration project including six additional acres of wetlands storage and an improved public park.
ACHD can continue to discharge historical stormwater flows into the SID facilities and they have potential surplus storage in the Hyatt Reserve for future projects that discharge to SID facilities.
City of Boise residents received a recreational area with a wildlife preserve to enjoy surrounding birds and animals, and an outside educational facility. The space also includes restrooms and a porous pavement parking lot. “Educational signage at the site discusses stormwater runoff, wildlife and wetlands types,” says Wyllie. “There are a lot of educational components.”
For more information, visit Hyatt Hidden Lakes Reserve.