SFEI review 2
Comments from Tim Beechie
Northwest Fisheries Science Center
In general I had a much better sense of the overall aims of this project although there is
still a little mixing of salmon recovery goals and sediment TMDL goals. I encourage the
group to continue efforts to keep these two elements clearly defined, especially making it
clear that the sediment reduction effort is one element of a larger salmon recovery or
watershed restoration effort.
The following comments are focused on individual aspects of the analysis, and are
therefore somewhat fragmented.
Watershed history story boards:
I think that these are in good shape. What they illustrate clearly is that a lot has changed,
and that the story is complicated. To me, that is a sufficient message and I would avoid
overcomplicating them with more details. I understand our many suggestions to include
additional details, but you might consider filtering the suggestions with criteria such as:
(1) what is the overall message of the slide or illustration?, (2) does the new detail
enhance the message or detract from it?, and (3) will the audience see and correctly
interpret the added detail? When I look at the history story boards it seems the message is
not really in the details. Rather, it is in the general trajectory of land use changes. On one
hand the landscape picture gets more complicated as more and more land uses are added,
while on the other hand the river gets simpler. I would reserve other details for other
illustrations since the audience probably won’t be focusing on specific pieces the way we
are (or if they are it’s not likely to be on the same things that we think are important).
Other story boards/illustrations:
Ditches on fans: I think the illustrations of altering flow routing across fans are in good
shape. They don’t show every possible permutation, but they don’t really need to; the
point is to show that connectivity has been changed in a few key ways.
Channel incision: These are on the right track; details need some fixing as the panel
pointed out. On several of these it would be good to have some simple bullets that
highlight the main changes. An example is shown in Figure 1 here (next page), which
we’ve used for incised channels in semi-arid tributaries of the Columbia River. It’s not
ideal, but people seem to get the main points fairly quickly.
The two analysis pathways
Identifying and prioritizing sediment reduction actions
The sediment budget approach to identifying sediment sources and potential restoration
actions seems to be on track. At the next meeting it would be good to see a summary of
where the sediment TMDL project sits. I imagine a summary including (1) the sediment
TMDL goals (if I recall correctly it was to reduce management related inputs by 50%?),
(2) a summary of the sediment budget results, (3) a summary of the restoration actions
that can be taken in a reasonable time frame (i.e., those that are feasible), (4) a projection
of how close this should come to achieving the goal, and (5) and outline of the
monitoring plan (in this meeting we recommended focusing on measuring source
reduction rather than stream channel or biological parameters downstream).
The broader watershed restoration plan
At the next meeting it would also be good to see a summary of the status of this project.
As above the summary could include (1) the watershed restoration goals (need to be
specific about whether restoration targets salmon recovery or general river health), (2) a
summary of the principle channel alteration, flow, riparian, and sediment results, (3) a
summary of the restoration actions that you think are necessary, (4) a projection of how
close this should come to achieving the goal, and (5) and outline of the monitoring plan (I
think we recommended focusing on measuring measures of river health in addition to
The flow analysis
This is coming along well, although the specific questions should be clearly stated up
front. The questions seem to be (1) are land uses changing peak flow or low flow
magnitudes, (2) is reservoir storage changing peak flow or low flow magnitudes or
timing. One point of confusion for me was in the gages used in the analysis. It sounds
like the analysis is limited to gages with little or no reservoir storage. However, one
component of change is the one currently sought (changes in flow due to land uses like
impervious surfaces), but another is the more direct changes induced by reservoir storage.
It seems important to look for effects of reservoir storage on both tributary and mainstem
flows, which would be done by comparing gages with storage to those without. For the
first question, the gage selection you have now is appropriate.
For the landuse-caused changes, I think the approaches of looking at (1) runoff co-
efficients and peak flows and (2) low flow durations are the right ones. The peak flow
return intervals show that recent frequent floods are smaller than ~50 years ago while the
rarer floods are larger. I’m curious how much reservoir storage might drive these
differences (at least at Napa), where storage is conceivably high during small events
when increased inflows are not enough to warrant increased releases, but conceivably
high during large events when inflows require rapid releases to prevent overfilling the
reservoir (a pattern that seems to occur with some dams in the Pacific Northwest).
It didn’t seem there was a clear definition of ‘fully functioning’ habitats for the historical
reach types. Since full function is not the same everywhere, these should be a little more
specific. I can imagine showing these in terms of some specific species so they become
more concrete. For example, it was clear that full function in some of the mainstem
reaches still meant they were dry for parts of the year, but that did not pose a problem for
the Chinook salmon life history which is adapted to the flow regime. By contrast, full
function in some tributaries means year-round flow, which is essential for steelhead. In
other words full function in the mainstem does not mean all species are supported, but
those species adapted to the historical regime should still be supported by the present-day
A couple things strike me as important that I hope come into focus as the project
1. The first is the conundrum of an incising channel despite historically increasing
sediment supply. This is an important part of understanding what matters most in the
present situation, especially with regard to how much sediment reduction actions really
matter in the context of salmon and the river ecosystem.
2. The second is the importance of floodplain restoration in ecosystem recovery. I’m
hoping that at some point you will be able to pull together some modeling of salmon
populations with the environmental history to help evaluate which habitat losses seem
I hope these comments are useful to you; you all are in the midst of a very interesting