ADMINISTRATIVE COMMITTEE

 

4.

CONSIDER EXPENDITURE OF FUNDS FOR DEVELOPMENT OF A LONG TERM STRATEGIC PLAN FOR LOS PADRES DAM

 

Meeting Date:

October 14, 2013

Budgeted: 

Yes

 

From:

David J. Stoldt,

Program/

Augment Water Supply

 

General Manager

Line Item No.:

1-8-1 / 5-7860.19

 

Prepared By:

Larry Hampson

Cost Estimate:

$146, 850

 

General Counsel Review:  N/A

Committee Recommendation:  The Administrative Committee reviewed this item on October 14, 2013 and recommended ___________.

CEQA Compliance:  N/A

 

SUMMARY:  Staff proposes to retain The Shibatani Group, Inc. to assist the District in developing a Long Term Strategic and Short Term Tactical Plan for Los Padres Dam.  The scope of services would include an analysis of surface storage expansion alternatives as well as a preliminary analysis of the effects of removing Los Padres Dam, which the National Marine Fisheries Service has proposed in its recent Draft Recovery Plan for South Central California Coast steelhead.  Results from this work will provide a basis for making recommendations to the California Public Utilities Commission in connection with California American Water’s (Cal-Am) recent General Rate Case filing (A13-07-002), which contains a proposal to carry out a $1 million feasibility study “...to determine the ultimate fate of Los Padres Dam.” 

 

Results of the work proposed by the Shibatani Group (Exhibit 4-A) may also inform MPWMD Board decisions concerning surface water storage in the Carmel River watershed and will describe the benefits and risks of the District acquiring Los Padres Dam and Reservoir. The technical and institutional information produced can be used as negotiating support with Cal-Am, NMFS, other public trust resource agencies, and vested stakeholders.

 

RECOMMENDATION:  Staff recommends approval of the expenditure of up to $146,850 in budgeted funds for assistance with development of a long term strategy for Los Padres Dam.  The Administrative Committee considered this matter at their October 14, 2013 meeting and voted to _____________.     If this item is adopted with the Consent Calendar, the General Manager would be authorized to enter into an agreement for services with The Shibatani Group for a not-to-exceed amount of $146,850.

 

IMPACTS TO STAFF/RESOURCES:  Funds for this work are identified in the proposed FY 2013-14 Budget, Program Line Item 1-8-1, Other Water Supply Projects – Water Allocation/Water Rights.  The proposal from The Shibatani Group anticipates expenses of $146,580. 

 

BACKGROUND:  In an April 13, 2013 letter to California American Water (Cal-Am), the National Marine Fisheries Service (NMFS) states:

 

“NMFS strongly encourages CAW to resolve the fish passage and other potential take issues at L[os]P[adres]D[am] by completing a thorough feasibility study on the merits of either: 1) entirely removing the dam and restoring the reservoir area to its original environs; or 2) improving the dam with appropriate permanent fish passage modifications that allow for unimpeded, safe and effective, upstream and downstream migration of all life stages of S-CCC steelhead.”

 

The April 13, 2013 letter also pointed out that Los Padres Dam has impacted downstream habitat by blocking the natural sediment supply. In its 2012 Draft Recovery Plan for steelhead, NMFS recommended removal of Los Padres Dam; however, a June 5, 2013 letter from the California Department of Fish and Wildlife to NMFS lists several concerns about the draft recovery plan including:

 

“Dam removal may also have negative impacts to current habitat and available flows because, in many watersheds, the reservoirs provide the only source of consistent summer flows.  For example, the removal of the Los Padres Reservoir Dam could result in up to 10 miles of streambed going dry.  The Carmel River is currently wetted year round below Los Padres Dam and may be more suitable habitat than the stream habitat upstream of the reservoir.”

 

In its 2015-17 General Rate Case (GRC) application to the California Public Utilities Commission (A13-07-002), Cal-Am is requesting $1 million over three years to complete a detailed feasibility study to determine the ultimate fate of the dam (Exhibit 4-B).  The proposed schedule is to award a contract in mid-2015.  Concerning the long-term feasibility study, Mark Schubert, one of Cal-Am’s managers, states in his direct testimony that “California American Water only wants to propose a project that best addresses the concerns of NOAA Fisheries.” 

 

Cal-Am’s proposal for the study focuses on two alternatives – dam removal and restoration of reservoir capacity (partial or full) with additional habitat and fish passage improvements.  A preliminary cost estimate for sediment removal is provided, which ranges from $52 million to remove about 500 acre-feet of sediment to $100 million to remove all the accumulated sediment (i.e., about 1,250 acre-feet).  No costs associated with constructing upstream fish passage improvements, dam spillway modifications, or habitat enhancement activities downstream of the dam are provided. Cal-Am described in its testimony that a strategy would need to be developed for working with the District on how to best manage the Carmel River under either option, because of on-going environmental programs.

 

The risk to the District is that the Cal-Am feasibility study may overlook key issues that are relevant from a basin-wide water supply security perspective.  Issues that Cal-Am has not proposed to address in its feasibility analysis include an update to baseline hydrology (e.g., unimpaired flows), anticipated future extreme event hydrology, development of a model to predict changes to instream aquatic habitat, downstream floodplain implications, U.S. Forest Service future land and fire management practices, and the potential for developing additional on and off-channel storage within the watershed.  These issues are among many that should be part of any genuine investigation into the long-term viability of Los Padres Dam.  At this time, however, Cal-Am has committed to including only a subset of these important elements in its pending Feasibility Study for the dam.

 

Component studies necessary to evaluate the future of Los Padres Dam

 

There are several studies that should be carried out in order to fully evaluate options at Los Padres Dam, including:

 

·         Unimpaired flow analysis – this analysis would be used as the “baseline” for comparing changes in flow with various alternatives.  The most recent analysis of unimpaired flows was in 2002 using the District’s Carmel Valley Simulation Model (CVSIM).  This model is no longer available and is proposed to be replaced with a linked, surface-groundwater model for the Carmel River Basin (see related item in this Water Supply Planning packet).  Flow analyses are combined with aquatic habitat information to characterize the availability and quality of steelhead habitat under various flow conditions (see below).

 

·         Flow analyses associated with alternatives – several flow analyses involving different levels of diversions would be required in order to evaluate alternatives including: existing conditions and Cal-Am operations; future Cal-Am operations as proposed in the Monterey Peninsula Water Supply Project; partial reservoir dredging; full reservoir dredging; reservoir enlargement; and dam removal (with future Cal-Am operations). 

 

·         Updated instream flow study – NMFS completed recommendations for maintaining instream flows in 2002.  A modified version of those recommendations is currently being attached by SWRCB to all new permits issued for the Carmel River.  The 2002 NMFS study does not accurately reflect significant changes in river habitat conditions and Cal-Am operations over the past 25 years.   District staff is currently working with a consultant to develop an updated instream flow analysis using the Instream Incremental Flow Method (IFIM).  The study will likely take two years to complete.

 

The IFIM can be used to evaluate how changes in flow affect steelhead habitat and fish passage.  Alternatives being considered at Los Padres Dam would have significant effects on the flow regime in the dry season and could affect the flow regime in the “shoulder” seasons of late fall/early winter and late spring/early summer. 

 

·         Steelhead habitat evaluation of the Carmel River watershed – MPWMD’s 2004 evaluation of steelhead habitat in the watershed estimated that 50% of the spawning habitat in the watershed was upstream of Los Padres Dam.  Similarly, MPWMD estimated that 42% of the suitable rearing area in the watershed was above Los Padres Dam and that it was of exceptional quality due to its location within the Ventana Wilderness.  These estimates were based on habitat conditions between the 1980s and early 2000s and included the effects of unauthorized diversions.

 

The value of steelhead habitat both upstream and downstream of Los Padres Dam should be re-evaluated in the context of improvements to habitat in the main stem due to the removal of San Clemente Dam, stream restoration in the lower 15 miles of the river, proposed reductions in Cal-Am diversions, and any proposed gravel replenishment projects associated with sediment management at Los Padres Reservoir.  A combination study using IFIM and habitat suitability index assessments should be used to better understand the value of each reach of the river and each tributary and the potential for improvements downstream of Los Padres Dam.

 

·         Yield and cost/benefits analysis – increasing storage capacity at Los Padres Reservoir can be achieved through dredging, increasing the spillway elevation, or a combination.  Each alternative should be evaluated for costs and benefits to water supply.

 

·         Impacts analysis – Each alternative would have varying environmental benefits and impacts that may make them infeasible to permit.  An initial screening of alternatives should be carried out to rank alternatives and determine if there are fatal flaws.  For example, reservoir area at the existing spillway elevation is about 55 acres and increases slightly with elevation.  It is thought that with a 14-foot increase in the existing spillway elevation (about 800 AF in volume), the reservoir backwater would extend to the Ventana Wilderness.  A project that raises elevations above the level that reaches the Ventana Wilderness boundary would likely trigger the land swap approved by Congress in the late 1980s for the New Los Padres Project.  However, the status of the land swap would need to be investigated.  Because the dam is under the authority of the Division of Safety of Dams, any modifications to the spillway would require a permit from DSOD.  Modifications that trigger a Corps 404 permit process and change hydrology of the river would require formal consultation and a biological opinion from NMFS concerning potential impacts to steelhead.

 

·         Sediment management – Los Padres Reservoir is a more difficult and expensive site to address sediment issues than at the San Clemente Reservoir, where a unique situation allowed sediment to remain in place.  A fundamental issue with Los Padres Dam that needs to be addressed with any proposed project – dredging, removal, or enhancement – is both the short term and long term management of sediment.  The long term average sediment inflow is about 20 acre-feet per year or the equivalent of about 2,200 tandem truckloads of sediment annually.  Sediment starvation downstream of the dam continues to degrade the river through the armoring effect (winnowing of spawning gravel) and downcutting into the riverbed.  Failure to address this degradation will further threaten infrastructure near the river, may compromise efforts to reduce diversions, and may lead to further destabilization of streambanks in the lower 15 miles of the river.  However, an increased sediment load could also change the flood carrying capacity of the river, which in many areas can safely pass only up to about the 20-year return flood.

 

Water Supply Planning Committee Review

 

In addition to Carmel River water rights associated with the Aquifer Storage and Recovery (ASR) Water Projects 1 and 2, the District retains a permit from the State Water Resources Control Board (SWRCB) to divert up to 18,674 acre-feet per year (AFY) in direct diversions and diversion to storage.  These rights were originally granted in October 1995 based on SWRCB Decision 1632 and were associated with the proposed New Los Padres Reservoir Project to build a new 24,000 acre-foot reservoir on the main stem of the Carmel River.  Complete application of water is required by 2020 (i.e., facilities operational and used for water supply). 

 

At its August 14, 2013 and September 16,  2013 meetings, the MPWMD Water Supply Planning Committee discussed options to provide additional supply to the Monterey Peninsula that include expanding storage capacity at the Los Padres Dam site to greater than the original 1948 permit for 3,030 AF.  The option to expand capacity beyond the original volume is not currently included in the Cal-Am GRC application. 


At its October 8, 2013 meeting, the Committee reviewed the Shibatani Group proposal for developing a long term plan for Los Padres Dam.  Proposed tasks would be to evaluate the merits of retaining the Los Padres Dam and Reservoir and explore the potential for yield enhancement of the facility as part of a wider District effort to investigate new water supplies.  Results of this investigation into new supplies would be compared with the dam removal option.  The information generated would be consistent requirements for the studies described above.

 

By a vote of 3-0, the Water Supply Planning Committee recommended to the Board of Directors an approval of the proposal. 

 

EXHIBITS

4-A      The Shibatani Group Proposal for Services: Los Padres Dam and Reservoir Acquisition – Long-Term Strategic and Short-Term Tactical Plan

4-B      Schubert Testimony, Cal-Am Project 115-400100 Los Padres Dam Long Term Plan

 



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