Down goes Nelson

If you have the pleasure to visit Nelson Reservoir lately, you've probably notice the area looks drastically different.

Nelson Reservoir's water is typically drawn down in mid-August each year to an elevation of 2215.0 acre-feet each year, According to Jack Conner of the Bureau of Reclamation. This year, however, dikes C and DA are being modified to incorporate a new filter zone and drainage collection at the downstream faces of the dikes and portions of the existing conduits are being replaced and tied into the new filter and drainage system. In order to accommodate the work being done this year, the Nelson Reservoir has surpassed the 2215.0 acre-feet it is usually drawn down to and is now down to 2205.0 (roughly 8,472,100,000 gallons.)

The contractor selected to complete the Nelson Dikes Safety of Dams Modifications, Johnson-Wilson Constructors, Inc., has mobilized to the Nelson Dikes construction area, according to a press release from the Bureau of Reclamation. Reservoir drawdown operations began in late June and the reservoir was to be near an elevation of 2212.0 by the end of July. The reservoir was continued to be drawn down until the target elevation of 2205.0 feet is reached. This low reservoir restriction will remain in place until at least October 15, 2016. Refilling the reservoir is expected to occur in the spring of 2017, and will depend upon available water supplies.

Temporary road closures around the dikes are not anticipated at this time, the release stated. The North Nelson boat ramp will become unusable below reservoir elevation 2216.0 ft. All other boat ramps will remain open at Nelson Reservoir.

Nelson Reservoir, at its deepest, has a reported maximum depth of roughly 27 feet at reservoir elevation 2221.6, according to Conner. He said that the last work of this type conducted at the site occurred in 2000-2001 and has had this type of maintenance done several times since the site was originally constructed in 1915.