Garden City – The Ada County Highway District achieves a novel solution for disposing of stormwater, while the Settlers Irrigation District will get some much-desired flood protection under a pact signed Wednesday.
ACHD and Settlers officials said Wednesday that the deal provides a new working relationship for the entities, one that is long overdue.
“We now have a means to build and expand Ada County’s roadways and a way to reduce any risk of flooding,” said Rebecca Arnold, ACHD president.
The settlement will also be a boon for the Hyatt Wetlands, providing new water supplies and increased acreage to the nature park being developed by the City of Boise. The sometimes water-starved Hyatt will receive stormwater from Maple Grove Road – and potentially excess water from Settlers canal during major storm events.
“This is a win-win-win,” said David Vail, Settlers president. “This final result proves a negative can produce a positive.”
The case began in early 2006 when ACHD sued Settlers when the irrigation district refused to grant permission to cross a canal to finish the extension of Maple Grove Road to Chinden Boulevard. In exchange for permission, Settlers wanted ACHD to remove two stormwater drains (outfalls) from the canal.
In 2007, Settlers filed a countersuit, asking a court to order the removal of 110 stormwater drains from the length of its canal system. Experts hired by ACHD estimated it could cost of minimum of $500 million to replace all of the drains with treatment ponds.
“Cutting off those drains could have turned ACHD into a pond-building entity instead of one that builds roads,” Arnold said.
After 14 months of delay, the Maple Grove Extension was finished in 2007, but the lawsuit continued.
Significant aspects to Wednesday’s settlement include:
• Existing storm drains into the Settlers system can remain.
• No new drains will be allowed, and the amount of water flowing into the drains cannot be increased.
• Settlers Irrigation will pay ACHD $100,000 for the delay in the Maple Grove Extension project.
• ACHD will build a spillway and automated water control gate from the canal connecting to the Hyatt Wetlands.
• ACHD will spend more than $1 million improving the Hyatt Wetlands and adding the water control structure.
o $297,000 to buy 10 acres next to the Hyatt Wetlands from the Meridian School District (June 2010)
o $600,000 to develop wetlands
o $132,000 to build water control structures
• Creating six acres of new wetlands in the Hyatt will give ACHD mitigation credits (estimated value: $1.1 million), which will be used to offset wetland impacts of future roadway improvements.
• Because of the expansion, the Hyatt will be able to accept more than 40 more acre-feet of water.
o The amount is equivalent to the 20 cubic feet per second of water flowing for 24 hours in the canal – the amount of water Settlers says it needs to divert in a big storm to prevent flooding.
An acre-foot of water is the amount of water needed to cover one acre of ground, one-foot deep.
Forty acre-feet of water is about 13 million gallons.
• ACHD must continue to abide by its National Pollution Discharge Elimination System permit requirements – i.e., meet applicable federal and state water quality standards for stormwater.