The great water exchange

Tempe Town Lake

Tempe draining about half of Town Lake into SRP’s Grand Canal

If you’re a dragon boater or a kayaker, or you just happened to drive by Tempe Town Lake recently and wondered why the water levels had dropped and the lake closed for water activities, know that there’s a good reason for that.

Updated image: North side of a dried up Tempe Town Lake – March 8, 2016
Tempe Town Lake draining

Tempe needs to drain the lake so that the rubber bladder dams at the west end can be removed and a new hydraulically operated steel dam system can be activated.

But before doing so, city officials, hoping not to see 3,000 acre-feet of water go, well, down the drain, came to SRP to work out a plan to salvage as much of it as possible for reuse.

SRP is able to take about half. That’s because the only point water can be pumped from is about midpoint on the lake, and at some point the water will be too far west for it to be possible to be drawn into the pumps. The remaining water will be drained down the riverbed.

Just 1 acre-foot contains nearly 326,000 gallons, or about the amount of water used by an average American family of four in a single year. That’s a lot of water that can be saved for good use, including irrigation for parks or lawns.

In return, SRP will use Salt and Verde river water to refill the lake after the rubber bladder dams have been removed and the new steel dam system is ready.

“A water exchange is similar to how a bank loan is handled, except it involves water,” said Rich Siegel, Senior Municipal Planning Analyst, Water Rights & Contracts.

The lake should be drained by mid-March and is scheduled to be refilled through SRP’s system by mid-April.

How the water is pumped out of the lake
lakesmall4
1. The water is brought up from the lake via four pipes.
lakesmall3
2. Large pumps channel the water into two larger pipes.
lakesmall1
3. The pipes travel under Loop 202 and down into Papago Park.
lakesmall2
4. The water empties into the Indian Bend pump ditch and goes through a trash rack to an underground culvert, where it travels to the Grand Canal.
(Photos: Michael McNamara, Heather Albert and Adam Fuller)
Heather Albert

Heather Albert

Heather is an Arizona native who works in Corporate Communications, overseeing SRP’s weekly employee publication. Outside of work, she likes to play sand volleyball, take her dog hiking, travel, read and bake pies.

More Posts

  • Sniper Merc

    My GF works in the building right across the river 🙂 HI BABY!!! (WAVES)