Alden has numerous large buildings housing a wide array of hydraulic and fisheries test facilities. A testing facility specifically designed for evaluating fish passage and protection technologies was constructed at Alden in the early 1970s. Most testing is conducted in this 58,000 gallon flume, but smaller tanks and customizable systems are also available. To ensure that fish acquired for testing are maintained in a healthy condition, state-of-the-art fish culture systems hold a wide variety of fish species (freshwater, estuarine, marine) and life stages (egg, larval, juvenile, and adult).
The test flume is a closed loop system with a main channel that is 6 ft wide by 7 ft deep and has a maximum flow capacity of 100 cfs. Depending on water depth, flow velocities up to about 3 ft/sec can be achieved. The downstream end is wider and deeper than the main channel, and a separate side channel provides additional space for installation of more than one technology at any given time.
Using this facility, we have conducted biological and/or engineering performance tests with the following technologies:
- Modified traveling screens (Ristroph screens)
- Cylindrical wedge wire screens
- Air burst systems
- Geiger Multi-Disc™ screens
- Aquatic filter barrier
- Bar racks (angled and perpendicular to approaching flow)
- Barrier nets
- Louvers
- Behavioral deterrents (strobe light, sound, air bubble curtain)
- Modular Inclined Screens (MIS)
- Angled flat panel screens
Alden can design and construct any test facility needed to obtain engineering and biological data for all types of upstream and downstream passage and protection technologies for water intakes. Large test facilities have been constructed to evaluate fish survival in fish return systems and through a fish-friendly turbine runner. The turbine test facility is a 50 ft long test loop with fish injection and collection systems. The test loop has 3-4 ft diameter pipe, a 3 ft flow meter, and a 2000 HP pump capable of circulating about 110 cfs at 85 ft head.
