The Murray-Darling Basin is the breadbasket for Australia much the same way as the Sacramento-San Joaquin Basin is a primary breadbasket for the United States. And just like in California, complex issues like water allocation, climate change, water quality, salinity, and environmental degradation are at the forefront of water resource planning in the Murray-Darling Basin. A comparison of the issues facing both basins was the topic of a special lecture symposium held recently in Brisbane, Australia.
CALFED lead scientist Cliff Dahm participated in this symposium hosted by the Australian Rivers Institute in Brisbane, Australia.
The US Fish and Wildlife Service and a CALFED Science Fellow from the University of Washington have conducted several studies to assess the survival of outmigrating juvenile Chinook salmon through the lower portions of the Sacramento and San Joaquin Rivers and through the Delta. Both projects were spotlighted during recent CALFED Science Program brown bag seminars.
The main factors studied include migration routes (main stem of the Sacramento River versus interior of the Delta), and water operations parameters (open or closed gates or barriers, export rates, and combinations of export rates and outflows).
Initial results from a three-year CALFED Science-funded research project showed that most delta smelt released into Clifton Court Forebay died there before they ever reached the louvers and screen at the State Water Project’s (SWP) Skinner Fish Facility where fish are salvaged for return to Delta waters.
This pilot project is the first experimental evaluation of the relation between delta smelt salvage at the Skinner Facility and underlying entrainment losses at the SWP in the south Delta. Fish are considered “entrained” when they enter a diversion point, which for the State Water Project is Clifton Court Forebay.
If corroborated by future tests, this could have implications for the management of Clifton Court Forebay and/or regulatory accounting of smelt loss at the SWP.
The Skinner Fish Facility was originally designed to salvage fish species other than delta smelt such as Chinook salmon and striped bass. Entrainment losses in Clifton Court Forebay and fish salvage efficiency have been estimated for these species in previous studies, but do not necessarily apply to delta smelt.
What are the forms of mercury in the Delta and where did they come from? How dangerous is mercury to humans, fish and wildlife and what can be done about it? – Mary McTaggart, Delta resident