South Lahontan

Ordinary High Flows and the Stage–Discharge Relationship in the Arid West Region

U.S. Army Corps of Engineers (USACE) | July 14th, 2011

The Ordinary High Water Mark (OHWM) defines the lateral extent of non-wetland waters and is regulated as “Waters of the United States” under Sec. 404 of the Clean Wat

The Ordinary High Water Mark (OHWM) defines the lateral extent of non-wetland waters and is regulated as “Waters of the United States” under Sec. 404 of the Clean Water Act. Previous research has developed a reliable and repeatable methodology for identifying the OHWM on ephemeral and intermittent streams in the Arid West using the physical features of the channel (Lichvar and McColley 2008, Curtis and Lichvar 2010). This study expands upon the previous reports by providing an analysis of how gage data may be utilized in OHW determinations. We clarify the methodology for using gage data, review the potential errors encountered in developing a stage–discharge relationship, compare the position of the gage-predicted OHWM to the field OHW signature, and determine the recurrence interval and flow duration of OHW events. The field OHW signature often is not associated with a 2-year flood event like many assume, but ranges from <1- to 15.5-year flood event. This large variation in recurrence intervals for the field OHWMs makes it impossible to define the frequency of the ordinary high flow from gage data because the OHW event is unique to each channel.

Origins of Extreme Climate States during the 1982–83 ENSO Winter

American Meteorological Society (AMS) | November 1st, 1997

Owens River Water Trail

Inyo County | September 1st, 2015

The Owens River Water Trail is a signature recreation project—the first dedicated water trail on a river in California. The project creates a 6.3 mile water trail on th

The Owens River Water Trail is a signature recreation project—the first dedicated water trail on a river in California. The project creates a 6.3 mile water trail on the newly re-watered Lower Owens River in the scenic Owens Valley that is solely dedicated to kayaks, canoes, and other paddlecraft. Recreationists will find well designed parking areas, accessible paths to the river, and formal paddlecraft entry and exit points.  The Owens River Water Trail is also improves aquatic habitat; opening up the river and improving transport of organic sediments. The Lower Owens River is a component of the Lower Owens River Project (LORP) which, in addition to ecosystem recovery promotes sustainable recreation. The area of the proposed water trail has a moderately wide channel characterized by large areas of open water separated by relatively short lengths of channel that are obstructed or bridged by bulrush and cattail (collectively referred to as tules). Tules and coyote willow line the margins of the open water channel; ponds open to salt grass meadow.  Tree willow is the dominate overstory. The river has a sustained 40 cfs flow and a yearly seasonal habitat flow of up to 200 cfs. The project is expected to improve water quality. Years of low flows prior to 2006 allowed tules to colonize the channel. In places, thick beds of tule roots completely cover the river bottom and vegetation blocks the channel. The seasonal habitat flows meant to move muck out the system are diminished in the vegetation and the buildup of organic material, derived from decaying tules, cannot be effectively flushed by the habitat flow. The project improves water quality by opening these blockages. The newly established channel will better fit the river’s hydrograph and is expected to improve flushing of organic sediment and protect the fishery. Inyo County and LADWP jointly manage the LORP. A preferred Recreation use plan for the LORP, which has at its core a river trail, has the support of LADWP and parties to the MOU, and was developed by a diverse range of stakeholders including the LADWP, conservation organizations, ranchers, anglers, students, area Indian Tribes, local, state, and federal agencies, local businesses, and the general public. A water trail on the Lower Owens River has popular support, and now area businesses, local agencies and NGOs are meeting to discuss forming a Lower Owens River stewardship group. The entire project area is owned by the City of Los Angeles and is open to daytime use by the public. The Owens River Water Trail is 2.5 miles from the center of Lone Pine, easily accessible by bike or car. Lone Pine aspires to be identified as a River Town; this project establishes that connection. The Lone Pine economic plan associated with the project includes a concessionaire running regularly scheduled drop-offs and pick-ups of boaters between the river and the many local hotels.

Owens Valley Groundwater Basin Final Groundwater Sustainability Plan

Owens Valley Groundwater Authority | December 9th, 2021

The Owens Valley Groundwater Basin and Fish Slough subbasin (Basin) were assigned a low priority status by the California Department of Water Resources (DWR) and are not

The Owens Valley Groundwater Basin and Fish Slough subbasin (Basin) were assigned a low priority status by the California Department of Water Resources (DWR) and are not required to be managed by a Groundwater Sustainability Agency (GSA). GSAs in low priority basins are encouraged to complete a GSP. Following the adoption of the Sustainable Groundwater Management Act (SGMA), the Basin was originally ranked as medium priority, but DWR proposed it be assigned high priority and ultimately ranked the Basin as low priority in December 2019. Despite the uncertainty in the Basin ranking before the final ranking was announced the Owens Valley Groundwater Authority (OVGA) elected to prepare a GSP for the Basin. This document is the GSP, and it was developed in accordance with Sustainable Groundwater Management Act (SGMA) statutory and regulatory requirements. This GSP describes the Basin, develops quantifiable management objectives that account for the interests of beneficial groundwater uses and users, and identifies a group of management actions that will maintain sustainable conditions in the Basin for 20 years after plan adoption. This GSP also contains steps a GSA could undertake to manage pumping to address declining water levels in a portion of the Basin. Preparation and implementation of the GSP by the OVGA is discretionary as long as the Basin remains very low or low priority. This GSP does not pertain to lands in the Basin that are exempt from SGMA, e.g. Federal and state owned lands, Tribal Reservations, and Los Angeles Department of Water and Power (LADWP) lands managed pursuant to the Long Term Water Agreement (LTWA). LADWP lands in Inyo County are referred to as adjudicated; other lands in the Basin are referred to as GSP lands in this document. Los Angeles-owned lands in the Basin in Mono County are not exempt from SGMA. Due to size, the file has been divided into five parts. Part 1, Part 2, Part 3, Part 4, Part 5

Paying for California's Water System

Public Policy Institute of California (PPIC) | May 31st, 2021

Paying it Forward: The Path Toward Climate-Safe Infrastructure in California

Climate-Safe Infrastructure Working Group | September 1st, 2018

Performance of Fire Danger Indices and Their Utility in Predicting Future Wildfire Danger Over the Conterminous United States

American Geophysical Union (AGU) | November 20th, 2023

Petition for 2023 Drought Emergency Regulation or Other Emergency Action to Protect Nesting Birds, Water Quality, and other Public Trust Resources at Mono Lake

Mono Lake Committee | December 16th, 2022

Piloting a Water Rights Information System for California

Center for Law, Energy, and the Environment (CLEE) | July 15th, 2021

California’s complex water management challenges are growing and intensifying. Systemic stressors like the more frequent and severe droughts and floods driven by climat

California’s complex water management challenges are growing and intensifying. Systemic stressors like the more frequent and severe droughts and floods driven by climate change are only making it harder to respond. Accordingly, California needs to dramatically improve the ability of local, regional, and State entities to make agile and effective water management decisions. We believe doing so will require enhanced understanding of our water resources and how they align with the needs of a range of agencies and stakeholders. Water rights data provide a crucial opportunity for advancing this understanding. We find that modernizing water rights data is feasible, affordable, and can increase transparency and clarity for better decision-making.

Plan writing as a policy tool: instrumental, conceptual, and tactical uses of water management plans in California

Journal of Environmental Studies and Sciences (Springer) | February 24th, 2022

Numerous environmental regulations require organizations to codify prospective activities in a written plan. However, evidence suggests that many plans are never implemen

Numerous environmental regulations require organizations to codify prospective activities in a written plan. However, evidence suggests that many plans are never implemented, raising questions about why public agencies continually require plans, whether mandating plans allows agencies to meet their policy aims, and what additional purposes plans serve. Adopting concepts from literature on research utilization, we develop a plan use typology, defining instrumental use as occurring when the requirement to write a plan directly addresses a stated policy problem, conceptual use as occurring when the requirement to write a plan indirectly addresses a policy problem by raising awareness of an issue or improving governance capacity, and tactical use as occurring when the requirement to write a plan serves a political or symbolic purpose unrelated to solving the policy problem. We then apply the typology to four California statutes that require local and regional utilities to write water management plans. We first assess the statutes to identify the goals underlying the requirement to write a plan and assess what plan uses are emphasized in guidance documents and the written plans themselves. Lastly, we interview the plan writing organizations to capture their perspectives on the value and limitations of these plans. We find that legislators turn to plans to support instrumental and conceptual goals but that the plans themselves and the way they are used by authoring agencies primarily serve conceptual and tactical uses, suggesting a disconnect between the policy goals underlying plans and their actual use.