Reduced Pine Flat Releases Clear Kings River Runoff Capacity As New Atmospheric River Arrives
March 14, 2023
F O R I M M E D I A T E U S E
For More Information, Please Contact:
STEVE HAUGEN, Kings River Watermaster, (559) 217-5249
RANDY McFARLAND, Public Information Consultant, (559) 260-2775
Rain is again falling this morning over the Kings River foothill watershed but arrival of a second atmospheric river event in less than a week has been matched with plenty of river carrying space for uncontrolled runoff from the pesky Mill Creek tributary.
An unprecedented temporary Pine Flat Dam river-release strategy is again at work. It proved successful in largely protecting the Kings River’s valley reaches from what likely was record inflow that last week was spawned in foothill streams. The U.S. Army Corps of Engineers Monday began reducing the dam’s river release to a fish-maintenance flow. Since Monday evening, that release has been only 50 cubic feet per second.
The action was taken in anticipation of new atmospheric river tropically-spawned warm rain that began spreading across the valley early this morning, in significantly lighter amounts than the previous event.
Kings River Water Association’s watermaster, Steve Haugen, said today the KRWA, its 28 water agencies and the Corps of Engineers are again cooperating on the releases. As was the successful result last week, the present reduction in releases from Pine Flat is essentially partially “draining” the river downstream to make way for anticipated flood flows from Mill Creek. That unregulated stream, which usually carries small flows or none at all, is forecast to reach a peak discharge of 9,550 cubic feet per second to the Kings River, a mile downstream from Pine Flat Dam, around midnight tonight. Last week, Mill Creek flows to the river reached 18,860 c.f.s. but the “draining” strategy downstream prevented all but localized high water problems.
Kings River flows past the Reedley and Kingsburg areas have already fallen dramatically today, Haugen reported, and by dawn were being reported through the Laton area. Between the intentional channel “drainage” and lower than expected Mill Creek discharge, the Corps of Engineers is planning to begin resumption of important Pine Flat Dam flood releases early.
Considerably bigger potential problems are in the future. “What we’ve gone through is just the beginning,” Haugen said. “We can expect these large amounts of Kings River flows or more for the rest of the season.” The series of potent storms since Christmas has created—despite recent warm rains to fairly high elevations—what may be the biggest Kings River watershed snowpack ever observed.
At least one agency is predicting April through July peak season runoff to Pine Flat Reservoir is likely to be near or above all-time record runoff amounts. Those marks were established in 1983.
Kings River flows into Pine Flat Reservoir were very high during the recent storm event but Haugen said the inflow has been steadily dropping. The reservoir still has more than one-fourth of its one million acre-foot capacity remaining and this morning contained 690,000 acre-feet.