Keywords:groundwater recharge, urban water conservation
Facing a fourth consecutive year of drought in 2015 and consequential threat of curtailments, farmers in the Delta proposed a voluntary program to...
Facing a fourth consecutive year of drought in 2015 and consequential threat of curtailments, farmers in the Delta proposed a voluntary program to significantly reduce their surface water diversions during the critical summer growing season. This is a report describing the context, origin, objectives, regulatory framework, implementation and results of that program.
The establishment and management of a National Ground-Water Monitoring Network (NGWMN) in the United States would represent a significant achievement in water-resource management....
The establishment and management of a National Ground-Water Monitoring Network (NGWMN) in the United States would represent a significant achievement in water-resource management. The need for ground-water monitoring focused on the major aquifers and aquifer systems in the USA is increasingly important as a key element of sustainable ground-water resource management and use.
The National Framework described in this report provides detailed information and recommendations for developing and operating a national ground-water monitoring network that would provide ongoing data collection on ground-water quantity and quality. These data will be available to the public and will be critical for addressing ground-water management issues at the Federal, State, Tribal and local levels. The data will be particularly useful for “state of the resource” assessments requested by State Legislatures and the U.S. Congress. The National Framework was developed by the Subcommittee on Ground Water (SOGW), an ad-hoc committee under the Advisory Committee on Water Information (ACWI), which is a Department of the Interior Federal Advisory Committee.
In 2014, the California Natural Resources Agency and the U.S. Department of the Interior asked the authors of this paper, as four former...
In 2014, the California Natural Resources Agency and the U.S. Department of the Interior asked the authors of this paper, as four former leaders of The Delta Science Program, to summarize the challenges faced by water supply and ecological resource managers in this critically important region of Northern California. They concluded that the challenges are so
complex as to meet the definition of a “wicked” problem. Such problems can’t be ignored, defy straightforward characterization, and have no simple solutions. Yet they must be actively managed to maximize
beneficial and minimize adverse outcomes.
In this context, the following paper calls for Delta management to become more nimble and better coordinated.
Earthquakes and high water as hazards to Delta levees were reviewed in a seven-hour workshop organized by the Delta Independent Science Board and...
Earthquakes and high water as hazards to Delta levees were reviewed in a seven-hour workshop organized by the Delta Independent Science Board and held at the campus of the University of California, Davis.
Earthquake hazards in the Delta were described in terms of ground motions from Bay Area earthquakes, infrequent earthquake recurrence on faults beneath the Delta, and levee fills prone to earthquake-induced liquefaction. Large uncertainties attend all these seismic elements of levee hazard. Those uncertainties, according to presentations in the workshop, include whether the Delta ground motions previously computed for Bay Area earthquakes were too large. Hazards from high water were deemed greatest from the confluence of high river discharge, wind-driven surge and waves, and high tides. Major risk assessments have used available data on these hazards without mandates to advance the science.
Research needs and opportunities identified in the workshop include expanded observations of Delta ground motions, improved estimates of geologically recent displacement on faults beneath the Delta, further identification of liquefiable materials and mechanisms beneath levees, continued airborne measurements of land-level change, updated mapping of the contracting area of remaining peat, and fuller documentation of past levee failures. Recurring assessments of earthquake hazards and climate change provide precedents for periodic reappraisal of Delta levee risk.
The workshop brought together different parts of the diverse community of Delta levee specialists. Positive responses to the workshop suggest that it served levee specialists and outsiders alike.