Assessing site specific and cumulative impacts on anadromous fishery resources

Stream Flow Folks:

For thought and discussion:

In my stream flow file I found a document, NMFS/James R. Bybee to Mr. Harry Schueller/SWRCB, dated April 18, 2001 (my how the years fly by – the SWRCB should have a copy of this letter and it should be included in the record). This letter, by NMFS, was written to address a SWRCB staff report “Assessing site specific and cumulative impacts on anadromous fishery resources in coastal watersheds in Northern California”, January 23, 2001.

This document was written to address issue using discussion of subjects and concerns that NMFS has regarding the SWRCB policy proposal – some of which were addressed by the Joint CDFG/NMFS Proposed Guidelines (2000 – and – fixed 2002). The discussion included (short summary): General Approach – Cumulative Impacts related to numbers of un-permitted/unauthorized diversions (numbers in the thousands), limitations for “new” (what time frame constitutes new ?) onstream storage reservoirs, limiting the season of diversion to winter period when stream flow is the highest (Dec. 15 to March 31), providing bypass flows for the purpose of maintaining (recovering) the quality of downstream habitat. In general, NMFS argues that the Joint CDFG/NMFS Proposed Guidelines provided better (more useable solutions) by, 1) allowing diversions only when stream flows are higher then the February median – maintaining some semblance of the natural hydrograph, 2) restricting diversions to a maximum instantaneous rate of withdrawal – also to maintain a near-natural hydrograph. NMFS is critical of the proposed SWRCB policy which, 1) allows diversion when flows are higher than an established minimum (in this case the February median), 2) would establish the max total cumulative volume diverted based on estimated surface runoff – in normal years (discounting dry years) – and during a season from October 1 to March 31 – which would allow interception of all early flows needed by salmon (i.e. the early withdrawal season should not occur to January).

Instream Flow Policy – Northern California Streams – Issues from the NMFS 2001 letter are being highlighted to assess sufficiency of the newly (2008) proposed SWRCB flow maintenance policy to addresses issue and to show differences and potential shortfalls in the proposed policy to address issue.

Other issues:

Migration Barriers – Limitations on new (again define new) onstream dams, solely on basis of migration barrier issues, fails to address the flow needs issue – where the these dams normally fill during the early rain season – limiting critical flows during that period. In this case NMFS speaks strongly against allowing new onstream dams – except on Class III streams and only if the cumulative reduction in stream flow is not seriously (10%) reduced in fish bearing reaches. In addition, existence of such barrier that would preclude fish migration also precludes consideration of the potential to restore salmonids upstream form these unlauthorized and illegal structures. This is in conflict with newly proposed policy.

Season of Diversion – NMFS and the SWRCB seem to agree that the season of withdrawal should be December 15 to March 31 – with instantaneous flows outside the diversion season to be bypassed. This is linked by NMFS to another argument for limiting onstream dams. This is in conflict with the newly proposed policy – allowing October through March diversion.

Bypass Flow – NMFS disagrees with a bypass flow based on the February median flow. Bypass flows must protect all stream functions. “Bypass flows should not be some minimum value that does not fulfill all stream functions; instead it should be a dynamic fluctuating flow that effectuates all needed steam functions and processes” (ref: need to protect the natural hydrograph) The new policy addresses aspects of the flow issue but in a seriously convoluted way. Allowing illegal/unauthorized onstream dams (and diversions) that restrict flows and block migration will preclude attainment of the desired goal – habitat maintenance. NMFS suggests that a depth criterion may be necessary on some streams. This is not considered in the new policy, exception assessment, or cumulative assessment process. NMFS suggests that, both, CDFG and NMFS be included in the depth criterion assessment process.

Cumulative Effects – NMFS agrues for the Joint CDFG/NMFS Guidelines to avoid the “flatlining” of stream flows. NMFS argues that cumulative assessment of diversion impacts should include diversions under riparian right (or estimates of diversion under riparian right) – and – should be included in CEQA based cumulative effects analysis. NMFS, again, argues that the proposed period of permitted diversion starts too early. NMFS argues that historic habitats are not protected – nor are stream flows protected above migration restrictions. NMFS argues that assessments should include representative dry years. Lastly – NMFS recomends that assessment, reports, and cumulative effects analysis be presented in understandable form (this can be said for the wording of the new policy – itself). There is a conflict in the new policy with every issue mentioned in this paragraph.

Stream Flow Estimation – NMFS has some issue with reliance on USGS stream flow data (being uneven and sparse), and the Rational Runoff method. How will the unimpaired flow numbers be derived? The precipitation-based hydrologic model is given more support – but accuracy is questioned. This is a problem acknowledged by the SWRCB – with the suggestion that enforcement may be the key to the issue; ” …. a vigorous program to identify unauthorized diversions and bring them into the water rights process would be an important step in the right direction. If the problem is ignored it will only get worse.” (SWRCB 2000). NMFS agreed with the preceding statement. NMFS recommends a monitoring and research program for developing stream flow estimates. To date (during the last 10 years when this policy was on the table) little progress has been made in this area.

Verification – Variability and uncertainty regarding the adequacy and implementation of any set of guidelines or preceedures for regulating stream flow diversions for the purpose of protecting anadromous salmonids – demands verification or adaptive management. A program validating adequacy of such program should be put in place.

Compliance Monitoring – Any policy or program for limiting environmental impacts of water diversions on coastal streams will contribute little protection of fish and wildlife resources if there is inadequate oversight and enforcement of those programs or policy. “SWRCB must develop a credible compliance, monitoring, and enforcement program to ensure that requirements for bypass flows, rates of withdrawal, and a limited diversion season are met. SWRCB must also bolster its enforcement capability to discourage illegal appropriations of water. “(NMFS)

Given the above – short – review of issue, can it be said that the some areas of the new proposed policy is not consistent with NMFS concerns voiced in the 2001 letter to the SWRCB? Or – that the policy meets the criteria of meeting basic standards of being Understandable (Interpretable), Implementable, Enforceable? The Answer is that the policy is not there – yet.

This discussion, above, related to proposed SWRCB on insteam flows from 2000 and NMFS response (2001) can be applied to the current proposed Stream Flow – Maintenance policy now on deck. There are many open issues that need fixing. This discussion can be applied to that task.

Many of these comments are likely to appear in CAG’s final comments on SWRCB Stream Flow Policy. There are many more questions to be answered; e.g. How does the proposed policy and project review, with exceptions, fit in with CEQA?, How are unauthorized water transfers to be handeled?

Alan Levine