Douglas County PUD

Wells Dam diagnostic measurements (2002 - 2004)
Plant size - 840 MW



In late September and early October 2002, diagnostic and comparison flow measurements were conducted at Wells powerhouse Unit 3 using a transportable acoustic scintillation flow meter (ASFM) and a previously installed acoustic time-of-travel instrument (AVM). As a result of these comparative measurements, the District purchased the ASFM and a plan to assess the performance of all units in the plant was formulated.

Further diagnostic measurements were conducted in January 2004, when a single frame equipped with 30 measurement levels was deployed in each of the 12 intake bays of Units 1, 2, 6 and 10.



Wells Dam performance testing of all units (2004 onwards)

The planned program consisted of testing two units each year over five
years for the purpose of developing performance baselines and for optimizing Kaplan cams for all units. In late 2004, full flow measurement performance tests were completed on Units 3 and 4, and with two units tested every year after that, the testing of all 10 units was completed in 2008.

Following these performance tests a regular cycle of flow measurement and absolute performance testing is envisaged to continue into the future. Based on these tests, individual unit performance will be optimized by tuning the Kaplan wicket to blade cam relationship, known performance will be used in dispatching units, and more accurate flow measurements will be used to improve the coordination of Mid-Columbia river system operations. In addition, a regular program of periodic performance testing on the ten units will continue and will be used to monitor trends in performance.