Influence of Urban Areas on Surface Water Loss in the Contiguous United States

American Geophysical Union (AGU) | February 7th, 2022

Information for the Future: The West Side San Joaquin Valley Project

West Side San Joaquin Valley Coordinating Council, University of California, Water Resources Center | September 1st, 1970

Inland Empire Interceptor Appraisal Analysis

U.S. Bureau of Reclamation (USBR) | September 16th, 2013

The Santa Ana Watershed Project Authority (SAWPA) is a joint powers authority comprised of five member water districts that serve the vast majority of the Santa Ana Water

The Santa Ana Watershed Project Authority (SAWPA) is a joint powers authority comprised of five member water districts that serve the vast majority of the Santa Ana Watershed. The area served by SAWPA is located within Orange, Riverside and San Bernardino Counties of California, bounded by the Pacific Ocean on the west, the San Bernardino Mountains to the north, and the San Jacinto Mountains to the east. The five SAWPA Member Agencies are: • Eastern Municipal Water District (EMWD), • Western Municipal Water District (WMWD), • Inland Empire Utilities Agency (IEUA), • San Bernardino Valley Municipal Water District (SBVMWD), and • Orange County Water District (OCWD). These five agencies serve most of the Santa Ana Watershed. Population within the watershed has increased significantly in recent years, and this urban growth has put enormous pressure on the regional water supply, water quality and environmental/recreation resources. SAWPA’s mission is to plan and build facilities to protect water quality and enhance the water supply within the Santa Ana River Watershed. This mission includes the goal of achieving a salt balance in the upper Santa Ana Watershed. SAWPA developed the Inland Empire Brine Line (Brine Line), which was formerly known as the Santa Ana Regional Interceptor (SARI), for the purpose of exporting salt from the Santa Ana Watershed. Exportation of salt prevents its accumulation in the watershed and protects the quality of the potable water supply. The future of the potable water supply will continue to be dependent upon an economical means of collection, treatment and disposal of brine. The Brine Line collects and disposes of brine flow from the Santa Ana Watershed and is critical to SAWPA’s mission success. The Brine Line includes approximately 72 miles of pipeline in multiple branches which converge in the vicinity of Prado Dam near the City of Corona. It has a planned capacity of approximately 32.5 million gallons per day (MGD) and was planned for collection and exportation of approximately 271,000 tons of salt per year from the upper Santa Ana Watershed, east of the Santa Ana Mountains. Currently (2010 & 2011), average system flows are approximately 11.7 MGD and over 75,000 tons of salt are exported per year. An additional 21 miles of pipeline convey the combined flows to Orange County Sanitation District (OCSD) facilities for treatment and disposal by discharge to the Pacific Ocean. This pipeline has a nominal capacity of 30 MGD. The planned capacity of the Brine Line system (32.5 MGD) exceeds the hydraulic capacity of the pipeline from the Brine Line convergence near Prado Dam to the OCSD facilities. Furthermore, the present agreement between SAWPA and OCSD allows Brine Line flows to the OCSD system up to only 17.0 MGD, with a contractual right to purchase up to 30.0 MGD capacity.

Instream flow evaluation: Temperature and passage assessment for salmonids in Mill Creek, Tehama County

California Department of Fish and Wildlife (CDFW) | May 8th, 2017

Mill Creek is among the essential streams for recovery and perpetuation of wild stocks of Central Valley spring-run Chinook salmon (Oncorhynchus tshawytscha), and support

Mill Creek is among the essential streams for recovery and perpetuation of wild stocks of Central Valley spring-run Chinook salmon (Oncorhynchus tshawytscha), and supports Central Valley steelhead trout (Oncorhynchus mykiss; Armentrout et al. 1998). In addition, Mill Creek is utilized by fall-run Chinook salmon, late fall-run Chinook salmon, and Pacific Lamprey (Entosphenus tridentatus). The Recovery Plan for Central Valley Chinook Salmon and Steelhead (NMFS 2014) classified Mill Creek as a high priority Core 1 watershed because of its potential to support independent viable populations. Mill Creek is also identified as a priority stream in the State Water Resources Control Board (SWRCB) Instream Flow Studies for the Protection of the Public Trust Resources: A Prioritized Schedule and Estimate of Cost (SWRCB 2010), and the US Fish and Wildlife Service (USFWS) Final Restoration Plan for the Anadromous Fish Restoration Program: A Plan to Increase Natural Production of Anadromous Fish in the Central Valley of California (USFWS 2001). The California Department of Fish and Wildlife (Department) has interest in ensuring that water flows within streams are maintained at levels which are adequate for long-term protection, maintenance, and proper stewardship of fish and wildlife resources. The Department’s Instream Flow Program develops scientific information to determine what flows are needed to maintain healthy conditions for fish and wildlife. For each species of interest, life stage, and stream, relationships between flow and habitat are developed. The Department recommends using the federal Instream Flow Incremental Methodology (IFIM) to evaluate and develop instream flow criteria for projects which may affect California’s aquatic resources. The IFIM process, and instream flow evaluations, in general, should include broad consideration of the structure and function of riverine systems while also providing examination of five core components (i.e., hydrology, biology, geomorphology, water quality, and connectivity) of the riverine system. The Public Resources Code (PRC) §10000-10005 outlines the Department’s responsibilities for developing and transmitting flow criteria to the SWRCB for consideration as set forth in 1257.5 of the Water Code. The results from this study are intended to be used, along with other supporting information and data, to identify stream flow requirements necessary for upstream passage of adult Chinook salmon and steelhead into the upper Mill Creek watershed pursuant to the Department’s PRC mandate. Flow criteria for lower Mill Creek will be developed by the Department in a future document.

Integrated approaches to understanding and reducing drought impact on food security across scales

Current Opinion in Environmental Sustainability (Elsevier) | October 1st, 2019

Understanding the cross-scale linkages between drought and food security is vital to developing tools to reduce drought impacts and support decision making. This study re

Understanding the cross-scale linkages between drought and food security is vital to developing tools to reduce drought impacts and support decision making. This study reviews how drought hazards transfer to food insecurity through changes in physical processes and socio-environmental systems across a wide range of spatial and temporal scales. We propose a multi-scale, integrated framework leveraging modeling advances (e.g. drought and crop monitoring, water-food-energy nexus, decision making) and increased data availability (e.g. satellite remote sensing, food trade) through the lens of the coupled human–natural system to support multidisciplinary approaches and avoid potential policy spillover effects. We discuss current scale-dependent challenges in tackling drought-induced food security whilst minimizing water use conflicts and environmental impacts. 

Integrated Management of Delta Stressors: Institutional and Legal Options

Public Policy Institute of California (PPIC) | April 22nd, 2013

Despite some recent progress, the current institutional landscape for regulation and management of stressors in the in the Sacramento–San Joaquin Delta is highly fragme

Despite some recent progress, the current institutional landscape for regulation and management of stressors in the in the Sacramento–San Joaquin Delta is highly fragmented. A modest but powerful set of institutional changes can help produce better environmental outcomes while containing management costs—which are likely to exceed several hundred million dollars annually. This report lays out proposals for institutional reform.

Integrated Regional Water Management Plan for the Greater Monterey County Region

Greater Monterey County Regional Water Management Group | August 31st, 2018

Integrated regional water management (IRWM) is an approach to water resource management in California that is being strongly promoted by the State as a way to inc

Integrated regional water management (IRWM) is an approach to water resource management in California that is being strongly promoted by the State as a way to increase regional self-sufficiency. IRWM offers an approach for managing the uncertainties that lie ahead, particularly in light of climate change. The IRWM planning process brings together water and natural resource managers, along with other community stakeholders, to collaboratively plan for and ensure the region’s continued water supply reliability, improved water quality, flood management, and healthy functioning ecosystems—allowing for creative new solutions and greater efficiencies. This IRWM Plan has been developed for the Greater Monterey County IRWM region to fulfill the goals of IRWM planning in this region and to provide eligibility for State IRWM grant funds. Click here for the chapter index. Click here for the Greater Monterey County Integrated Regional Water Management Program home page

Integrated Regional Water Management: Stakeholder Perspectives

California Department of Water Resources (DWR) | April 18th, 2017

Integrated regional water management (IRWM) is the application of integrated water management principles at the regional level. IRWM brings local agencies and other stake

Integrated regional water management (IRWM) is the application of integrated water management principles at the regional level. IRWM brings local agencies and other stakeholders, with a range of water-related roles and interests, together to address water management needs collaboratively within self-identified regions accepted by the State. The practice of IRWM is rooted in the principle of regional control, recognizing that local and regional water managers and other stakeholders, working together in a collaborative, open, and transparent manner, are best suited and best positioned to manage water resources in their regions. Issues including limited groundwater and surface water supplies, drought, flooding, climate change, water quality, environmental degradation, aging infrastructure, economic constraints, recreation, and cultural considerations are addressed through coordinated and integrated actions. IRWM is helping California move away from a legacy of fragmented, divisive, conflict prone, and sometimes ineffective water management practices by supporting cooperation among agencies and other stakeholders. Integrated water management at the regional level: Helps provide for public safety. Supports a healthy economy. Supports ecosystem vitality. IRWM benefits accrue at the local and regional level, but also “roll up” to the state level, helping California meet its collective water management needs. When IRWM succeeds, California succeeds.  

Integrated Surface and Groundwater Modeling of Martis Valley, California, for Assessment of Potential Climate Change Impacts on Basin-Scale Water Resources

U.S. Bureau of Reclamation (USBR) | April 15th, 2015

This study develops a modeling framework to better understand surface and groundwater interactions in the Martis Valley Basin. Prior to the current study there were no ph

This study develops a modeling framework to better understand surface and groundwater interactions in the Martis Valley Basin. Prior to the current study there were no physical or statistical models of the Martis Valley Basin that could be used for long term water resource planning in the Basin. Currently, groundwater is the primary source for municipal and industrial water supply in Martis Valley, and surface water from the surrounding watersheds are partly stored in Donner, Prosser reservoirs and allowed to runoff into the Truckee River. This study presents the development, calibration, and verification of the physically based surface and groundwater GSFLOW model for Martis Valley. The model was calibrated for the historical 1981-2011 observed period. Various observations were used to calibrate the model during different periods, which helped verify the model’s ability to capture the dynamics of the hydrologic system. The model was calibrated to multiple fluxes and states in the hydrological system including streamflow, snow water equivalent, groundwater heads, and wetland and spring locations. In addition to comparing fluxes to multiple observations, consistency at internal gauges was also verified apart from simulating fluxes at the outlet. For future projections of hydrology, the GSFLOW model was forced with five future climate scenarios provided by CH2M HILL. Future simulations of snow water equivalent indicate reductions for all scenarios due to increasing temperatures. Groundwater recharge and its contribution to streamflow also decrease in the future for the warmer drier and hotter drier scenarios. The reduction in snowpack and earlier melt complicates the seasonally dependent nature of water resources and when combined, these results will likely add further stress to long term water availability in the Martis Valley Basin and the downstream consumers of the waters generated in the Basin.

Integrated Water Resources Plan 2015 Update

Metropolitan Water District of Southern California (MWD) | January 1st, 2016

In California water, uncertainty comes with the territory. Being unprepared for tomorrow, however, is simply not an option. The Metropolitan Water District of Southern C

In California water, uncertainty comes with the territory. Being unprepared for tomorrow, however, is simply not an option. The Metropolitan Water District of Southern California prepares for tomorrow with an evolving long-term water strategy known as its Integrated Water Resources Plan, or IRP. The inaugural IRP was adopted in 1996, with updates in 2004 and 2010. The 2015 IRP Update continues the tradition of assessing and adapting to changing conditions facing Southern California. The fundamental goal of the IRP is for Southern California to have as reliable a water system for tomorrow as the region has enjoyed for decades, regardless of the challenges that emerge along the way. Metropolitan plans to meet this goal through an adaptive management strategy that is the cornerstone of the 2015 IRP Update. Metropolitan was authorized by the California Legislature in 1928 to advance a regional approach to water supply in Southern California. Metropolitan’s initial mission was to construct the 242-mile Colorado River Aqueduct to its service area on the Southern California coastal plain. Metropolitan’s service area had an assessed property valuation of approximately $2 billion at the time. Now Metropolitan serves a six-county service area with a property valuation of approximately $2 trillion. Metropolitan imports supplies from both the Colorado River and Northern California via the State Water Project while investing in a variety of storage, local supply and conservation initiatives. Metropolitan has a long record of promoting alternatives to imported water supplies, dating back to the 1980s. With the IRP, that process became more formalized as a long-term strategy and official policy. Metropolitan has steadily diversified the future water portfolio for Southern California with each revision to the IRP. This update is no exception. Investments to maintain the reliability of imported supplies are complemented by an expansion of local supply development along with a reduction in demand through a variety of conservation and water-use efficiency initiatives. The necessary suite of actions evolves over time based on the water conditions of tomorrow. Updating the IRP creates a new baseline for managing into the future.