ITEM:††††††††††† INFORMATIONAL ITEMS/STAFF REPORTS

 

25.†††††† CARMEL RIVER FISHERY REPORT†††††

 

Meeting Date:†††††††††† December 15, 2003††††††††††††††† Budgeted:N/A

††††††††††††††††††††††††††††††††††††††††††††††† Program/Line Item No.: Aquatic

Staff Contact: Dave Dettman/†††††††††† †††††††††† Resources Fisheries, 2.4

††††††††††††††††††††††††† †††††††††† Beverly Chaney†††††††††††††††††††† Cost Estimate:N/A

 

General Counsel Approval:N/A

Committee Recommendation: N/A

CEQA Compliance:N/A

 

 

 

AQUATIC HABITAT AND FLOW CONDITIONS:During November 2003, Carmel River streamflow conditions were critical or lethal for rearing juvenile steelhead in the lower river and good for rearing fish upstream of Schulte Road Bridge.In October, mean daily streamflow recorded at the Districtís Carmel River Sleepy Hollow Weir gaging station averaged 8.0 cubic feet per second (cfs) and ranged from 7.3 to 9.2 cfs.

 

In November 2003, 0.87 inches of rainfall was recorded by Cal-Am at San Clemente Dam (SCD).The long-term November average at this site is 2.21 inches.For Water Year 2004 through the end of November, the total rainfall is 1.14 inches, or 39% of average.

 

The Carmel River Lagoon has been closed since July 2, 2003.In November, water depth continued to recover from the seasonal minimum in August, and now is ranging below five feet (See chart below).Streamflow at the Districtís Highway One Bridge declined to zero on July 27 and the riverfront receded upstream, ultimately stabilizing at point approximately 0.5 mile downstream of Schulte Road Bridge in early September.During November, the riverfront advanced downstream to near Cal-Amís Cypress Well in response to lower Cal-Am production.

 

Carmel Lagoon Water Level November 2003

 

 

SLEEPY HOLLOW STEELHEAD REARING FACILITY: As of the first week in December, the Facility is in demobilization mode, with only the river pumps running. The cooling tower has been shut down and staff is dip netting and electrofishing the fish from the rearing channel.By September 5, 2003, staff had stocked 28,327 fish at the Facility, or approximately one-half of the total number rescued from the lower river.As of November 30, 2003, an estimated total of 21,235 fish had survived including 13,385 fish on hand, 7,850 fish that were released, and 576 fish that voluntarily escaped to the river.To date, overall survival is estimated at 75% (21,235/28,327).

Turbidity Levels:Throughout this yearís rearing season, the turbidity of water at the intake to the Facility has been elevated due to continuing operations at San Clemente Dam, where Cal-Am has been required to lower the water surface elevation for the Interim Drawdown Project (IDP).The purpose of the IDP is to reduce the safety risk to downstream lives, following a seismic failure of San Clemente Dam.One environmental consequence of the IDP has been elevated turbidity of water released through the dam. During the IDP, turbidity levels in the reservoir have ranged from approximately 7 to 68 Nephelometric Units (NTUs), representing a 10- to 100-fold increase compared to typical pre-project levels (See inset chart below).[1] ††Currently, at the Facility intake turbidity is about 20 NTUís, significantly above pre-project levels and in a range that can affect fish health.While the increased turbidity has not apparently caused direct mortality to fish in the Facility, levels in the 15+ ranges appear to interfere with feeding, especially in rearing tanks, where particles tend to remain in suspension.In the upper end of the rearing channel, turbidity is equal to or slightly lower than river levels, but some of the suspended material settles out in the channel.

 

 

Sediment Discharge from San Clemente Dam and Early Release of Fish from Sleepy Hollow:As reported last month and described above, staff has been making early releases of fish from the Facility on account of the risk posed by the potential discharge of sediment from San Clemente Reservoir.As of December 2, 2003, this appears to have been a prudent decision because the sediment plume at the lower end of the inundation zone has piled sand and silt onto the upstream face of the dam, and is within 50 horizontal feet of the newly bored ports in the dam.Last month, staff reported that sediment could begin moving past the dam within the next six months to two years. It now appears (see photos below) that this could occur within the next month, or so, depending on streamflow, and whether Cal-Am is allowed to close the ports and let the reservoir spill at elevation 525 feet, or is required to hold the current elevation of 514 feet, whenever feasible.While there is some small risk associated with releasing the fish earlier, before the lower river has advanced to the lagoon, staff believes the risk of holding fish for an extended period, while increased sediment is mobilized during early storm events, is far greater.

 

 

December2, 2003 Photos of Sediment Plume in Lower San Clemente Reservoir

 

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[1] Source of Data:Preliminary data from Entrix Inc. (San Clemente Reservoir) and MPWMD (Sleepy Hollow Weir/San Clemente Ford