
So many dam building projects can go wrong, as we’ve covered in earlier posts, so it’s great to see one that’s actually being celebrated. Next week Tempe, AZ, will dedicate a new dam, the largest public works project in the city’s history and the largest hydraulically operated steel gate dam in the US.
As this site explains, the Salt River in this part of Arizona dried up a century ago as dams were built to capture water for users upstream, and the empty riverbed around Tempe for years became a dumping ground. The city eventually restored the area, creating a 261-acre man-made lake in a portion of the riverbed with water from the Colorado and Upper Salt rivers; the lake also captures stormwater runoff. Since it was created nearly 20 years ago, Tempe Town Lake has generated more than $825 million for the city, drawing 2.7 million people a year for various special events and recreational activities. Development around the lake also brings new taxes.
When it was first filled, the lake had four inflatable rubber dams to hold the water; they could be deflated when necessary to release water downstream. One of the four dams burst in 2010, however, and the city has been in the process of designing and building the new 900-foot steel dam that’s now coming online. The new dam has eight steel gates, each 17 feet high and more than 100 feet wide, which can be raised and lowered as needed to adjust the lake’s water level.
You can find more detail on the city’s website.
Continuing Education Credits From Forester University
Wednesday, May 4: Designing Effective Construction Sediment Containment Systems
This webinar is Module 3 of the Sediment & Erosion Control for Construction Sites Master Class Series, presented by Jerald S. Fifield and Tina Evans. If you’ve missed the earlier sessions, you can see them as on-demand webcasts. Click here for more information and to register.
Thursday, May 5: Stormwater Treatment Maintenance: What Works and How to Do It
Presenter Andrew J. Erickson of the St. Anthony Falls Laboratory in Minnesota explores the design and implementation of a stormwater treatment maintenance program—and how your program can accomplish it within your budget. Click here for more information and to register.
May 31 & June 2: Fluvial Geomorphology (for Those Who Skipped It in College)
This is Part 3 of the Surface Water Master Class Series, presented by David T. Williams. This module covers the latest theories, approaches, and tools in fluvial geomorphology. Past modules are available as on-demand webcasts. Click here for more information and to register.
Janice Kaspersen
Janice Kaspersen is the former editor of Erosion Control and Stormwater magazines.