Hoisting of the Drought Flag Put on Hold
By Steve Lafond, Special to Valley Ag Voice
It is said good things come to those that wait. For Kern County weather watchers, that wait amounted to two and a half months, from the first of the new year through the middle of March 2020. Only then, did a shift in the Pacific storm track begin to send much-needed precipitation the way of the Kern River watershed, Kern County mountains and southern San Joaquin Valley floor.
Beginning late on Sunday, April 5, 2020, a mid-winter type storm of historical significance moved into the south half of California, bringing record-setting precipitation to the mountain, valley and desert portions of Kern County. At Meadows Field, Bakersfield, 2.51” of rainfall was collected over the period of April 5-April 10, 2020, placing April 2020 as the third wettest month of April on record for Bakersfield. The rare super-storm, driven by a deep, moisture laden low-pressure system, left several feet of fresh snow in the Kern River Basin while sparking flash floods in the desert and foothill regions of the county. Based on data retrieved from the Kern snow sensor network, the average water content of the snowpack increased by approximately 2.8” as a result of the early April 2020 storm, helping to boost Kern River snowmelt runoff expectations by as much as 50,000 acre-feet. At Isabella Lake, 3.38” of precipitation was registered by the Corps of Engineers over the first 10 days of the month, already topping the previous April rainfall record of 2.77” set back in 1958. On April 8, 2020, 2.07” of rain fell at Isabella Dam, the highest daily amount of precipitation to be recorded for the month of April since records began in 1949.
Water Recreation in the Spotlight
Recreational opportunities appear bright for the Kern River Valley in 2020. The prospect of Isabella Reservoir storage nearing 250,000 acre-feet later this summer looks promising and would place Isabella Lake among the largest fresh-water lakes in all Southern California while helping to create near ideal boating and fishing conditions. The amount of Kern River water currently forecast for release from Isabella Dam during the upcoming May-August period should provide for stellar whitewater rafting conditions on the Lower Kern.
Long a much sought-after reach on Kern River for whitewater enthusiasts is the seven-mile stretch from Isabella Dam downstream to the Borel Power Plant. Historically, prior to its demolition as part of the Corps of Engineers Isabella Dam Safety Modification Project, the Borel Canal diverted up to 605 cubic feet per second (“cfs”) of water from Isabella Lake via the Auxiliary Dam outlet for power generation at the Borel Powerhouse. The Borel Power Plant, formerly maintained by Southern California Edison Company, has not been operated for power generation purposes since June 19, 2013. Today, all water released from Isabella Reservoir for use by downstream entities is passed from the Main Dam into the Lower Kern River, greatly enhancing the whitewater experience directly below Isabella, while benefiting the environmental aspects and aesthetics of this reach of river.
Corps Postpones Public Meetings
in Lake Isabella and Kernville
Sacramento–The U.S. Army Corps of Engineers, Sacramento District has postponed two public scoping meetings originally scheduled for March 18 and 19, 2020, in Lake Isabella and Kernville. The decision follows the California governor’s State of Emergency declaration to address the global COVID-19 outbreak. It is intended to help protect the health and welfare of all participants and to help reduce the risk of infection and spread of the Coronavirus.
The meetings were scheduled to collect public input on development of a permanent U.S. Forest Service visitor center as part of the Isabella Dam Safety Modification Project and will be rescheduled as soon as safely practicable. The Corps will provide notification of the new dates, when available, via public and media outreach. Public input remains an important aspect of the dam modification project, and will still be collected as part of the visitor center site selection process, however, public safety endures as the Corps’ number one priority and postponement of these meetings is the appropriate and responsible decision at this time.
Completed in 1953, Isabella Lake Dam is located approximately 40 miles northeast of Bakersfield. The reservoir is impounded by two earthen dams on the Kern River and Hot Springs Valley. Today, Isabella Lake and its dams reduce flood risk for Bakersfield and the surrounding region and is a primary water source for water users throughout Kern County. The Isabella Lake Dam Safety Modification Project will address overtopping, seismic, and seepage issues identified with Isabella Lake’s Main and Auxiliary dams to reduce the likelihood of dam failure. Construction of the dam modifications began in 2017 and is estimated to be completed by the end of 2022.
Facts, Notes & Highlights
May on the Kern
Over the long-term period of Kern River flow records, the maximum mean natural flow is 2,748 cfs and falls on the 29th day of May. The maximum median (middle value in a distribution) flow of Kern River is 2,355 cfs and lands on the 7th day of June.
May 10–On this date in 2019, Isabella Dam, California received 1.29” of precipitation as reported by the U.S. Army Corps of Engineers, the greatest 24-hour rainfall amount ever measured for May since records began. All told, May 2019 precipitation at the dam totaled 3.33”, shattering the previous monthly maximum of 1.74” set back in 1998.
May 11–On this date in 1969, the Kern River was flowing above 10,000 cfs for the first-time during May in the river’s storied history. During May of 1969, all-time maximum natural flow records were established for each day between the 9th and 22nd. May 1969 runoff on the Kern River was 617,968 acre-feet, maximum on record and largest known 30-day cumulative flow.
May 29–The greatest mean Kern River natural flow ever registered at First Point of Measurement near Bakersfield during the spring snowmelt period occurred on May 29, 1983, at 14,038 cfs. Snow water content at Upper Tyndall Creek (elev. 11,450’) in the Kern River Basin on May 29, 1983 still registered an incredible 53.6”. The average April 1 snow water content for Upper Tyndall Creek is approximately 27.7”.