Fun FactsEvery Year there is a weekend long event called the Green River Clean Up. Volunteers and other participants help clean the park and river then enjoy a party / BBQ at the end. Great Event for a Great River.
Here's some info we recieved on 5/12/10 regarding some recent work on the howard Hansen Damn:
During the conservation pool, the Corps has been testing and conducting in-depth investigations of the dam’s current effectiveness. During the fill, if there are any indications from readings or observations that the dam is behaving in any way not considered expected or normal, the reservoir level can be reduced appropriately.
Since April 21, when the reservoir reached the benchmark of 1,147 feet, the U.S. Army Corps of Engineers has conducted intensive monitoring, including scientists on the ground around the clock. Since early March, the Seattle District of the Corps has been slowly filling Howard Hanson Dam’s reservoir for its annual conservation pool.
Preliminary data from the testing results suggest that the grouted seepage barrier is reducing flow through the north abutment. However, this data is preliminary and should be considered provisional, as it has not been fully analyzed. During January 2009 flooding symptoms of internal erosion were observed, prompting an operational limitation of the dam at the headwaters of the Green River. This operational limitation raised the flood risk for those communities downstream to levels not seen for 50 years.
The Corps operates the Howard Hanson Dam project, which provides flood damage reduction to the cities of Auburn, Kent, Renton and Tukwila, as well as low-flow augmentation to the Green River for environmental benefits. More details and history about Howard Hanson Dam and the right abutment issue can be found at http://www.nws.usace.army.mil. |