Dr. Shawn Acuna is a research specialist that works out of Metropolitan’s Sacramento office; he does a lot of work on multiple stressor issues in the Delta, as well as Delta smelt and longfin smelt.
“The trawl data showing that they are widely distributed throughout the habitat; they can also be found in the ocean as well,” he said.
“So what are we really interested in when it comes to this relationship is why are we seeing that step change, what is the relationship governing abundance and flow relationship, and what factors may be contributing to that decline?” Dr. Acuna then presented a heat map of salinity from 2008 (a dry year) and 1990 (a wet year) which shows the difference in the salinity field when there is more fresh water; he noted that there is a lot more blue in the higher flow years than in the low flow years.
“What we’ve been seeing over the years in sampling from 2013, 2014, as well as in 2017, spawning seems to be happening in brackish water.
Especially since the wet years tend to correlate with higher abundance, we’re going to get a lot bigger signal, understand the distribution in the water column a lot better, so we’ll be doing trawls that allow us to understand at what depths these longfin are at.” They’ve been investing in the “smelt cam”, which is attached to the trawl, and as the fish travel through the apparatus, a photo is taken.
… And it can be used for adaptive management because this data can be fed into models, allow us to do these predictions, run the study, implement it, and do it again, and that will help us further our efforts along the way.” In summary … “The importance of our research is that our findings have found that a lot of the longfin smelt are spawning in brackish water, a lot more than had been previously thought,” Dr. Acuna said.
It does have more dependence on more local flows; Delta outflow will have an effect, but more local flows will also be key.” “How the fish behave in the water and where are they are in that water column is going to be important for understanding that survey data.
It doesn’t mean that it won’t happen, it’s just under these really high flow years, it’s possible.
Once the state takes that action, it would then issue a project order that approves the project as a component of the State Water Project, so that’s a decision that’s related to the state’s Environmental Impact Report and the California Environmental Quality Act.” After the environmental impact report is approved, there is a water code section 2081 permit that is issued by the Department of Fish and Wildlife that covers the state listed species: salmon, longfin smelt, Delta smelt.
Because you can’t have it so that ‘I only get water through the dual conveyance and I’m not going to get water through the tunnel’; I just don’t envision how that’s going to work.” Steve Arakawa said, “The way the contractors have been talking about Cal Water Fix is that it’s an integral part of the existing State Water Project, so it would be an added facility to the State Water Project and it would be up to DWR to operate that whole system, so there’s not Cal Water Fix water and then State Water Project water.”