Moisture vs. Wind-Dominated Flavors of Atmospheric Rivers

American Geophysical Union (AGU) | November 20th, 2020

Atmospheric rivers (ARs) are essential features of the global water cycle. Although AR definitions are commonly based on integrated vapor transport (IVT), ARs of a given

Atmospheric rivers (ARs) are essential features of the global water cycle. Although AR definitions are commonly based on integrated vapor transport (IVT), ARs of a given IVT can induce a wide range of surface precipitation and wind impacts. We develop an AR “flavor” metric that partitions AR IVT into moisture-dominant and wind-dominant components. We use this metric to create a climatological catalog of “wet” and “windy” ARs along the U.S. West Coast from 1980 to 2016. Windy ARs are generally associated with stronger surface winds than are wet ARs, with the largest differences at low IVT. Windy ARs are also associated with greater daily precipitation totals than are wet ARs, with the difference widening at higher IVT, notably over mountainous regions. Pacific Northwest ARs have become increasingly moisture dominated over 1980–2016, which has important implications for western U.S. water availability and flood risk.

Mojave Region Functionally Equivalent Storm Water Resources Plan

Mojave Water Agency (MWA) | October 4th, 2017

The State of California now recognizes the importance of incorporating storm water as a potential resource in a region’s water portfolio. Historically, storm water was

The State of California now recognizes the importance of incorporating storm water as a potential resource in a region’s water portfolio. Historically, storm water was thought of as a public risk (e.g., flooding) and a source of water quality impairment. Traditional approaches for storm water focused on diverting storm water into the storm drain system which ultimately and efficiently moved said water away from populated areas; the State is now supporting watershed-based approaches where storm water and dry weather runoff can yield benefits beyond flood control, such as water supply, water quality improvement, and habitat enhancement. To incentivize use of storm water, the State of California has linked storm water resources planning to state funding. Storm water and dry weather runoff capture projects seeking funding from any California bond act approved by voters after January 1, 2014 must be included in a Storm Water Resources Plan, which meets California Water Code. Regional water planning has a long history in the Mojave region. In 2005, agencies in the Mojave service area, that share a common concern for the area’s water resources, met and agreed to develop an Integrated Regional Water Management Plan (IRWMP). The Region’s first IRWMP identified, defined, and established strategies to capitalize on all water management opportunities that were present at that time or would become possible in the Mojave Region in the future. Since that time the IRWMP has acted as a forum for regular collaboration. The IRWMP is a living document and the regional objectives as well as strategies to improvement water management are regularly updated. The IRWMP was last updated in 2014. This Mojave Region Storm Water Resource Plan (SWRP) is an extension of the IRWMP process and is meant to bring an integrated and watershed-based approach to managing and creating benefits from storm water. This SWRP is regional and multi-agency. This SWRP includes all components required by the Water Code and will be submitted to the IRWM group. This SWRP will help entities in the Mojave Region identify, prioritize, and implement storm water projects.

Mojave Water Agency 2004 Regional Water Management Plan

Mojave Water Agency (MWA) | December 8th, 2005

This document supplements the Urban Water Management Plan element of the Mojave Water Agency (MWA) 2004 Regional Water Management Plan (RWMP). The RWMP is the master pl

This document supplements the Urban Water Management Plan element of the Mojave Water Agency (MWA) 2004 Regional Water Management Plan (RWMP). The RWMP is the master plan for MWA water management activities through the year 2020. This update provides additional information to meet 2005 Urban Water Management Plan update requirements, especially a projection of supply and demand through at least 2025. The 2005 Urban Water Management Plan is fully described in the 2004 RWMP as updated by this supplement with supply and demand projections through 2030.

Mokelumne watershed avoided cost analysis: Why Sierra fuel treatments make economic sense

Sierra Nevada Conservancy | April 10th, 2014

High-severity wildfires in forests of California’s Sierra Nevada pose a serious threat to people and nature. Although proactive forest management can reduce the risk of

High-severity wildfires in forests of California’s Sierra Nevada pose a serious threat to people and nature. Although proactive forest management can reduce the risk of high-severity wildfire, the pace and scale of fuel treatments is insufficient, given the growing scope of the problem. Using the upper Mokelumne River watershed as a representative case, we sought to answer the following question: Does it make economic sense to increase investment in fuel treatments to reduce the risk of large, damaging wildfires? Our analysis suggests that the economic benefits of landscape- scale fuel-reduction treatments far outweigh the costs of wildfire. 

Monitoring for Acidification Threats in West Coast Estuaries: A San Francisco Bay Case Study

San Francisco Estuary Institute (SFEI) | June 6th, 2017

The estuaries of the U.S. Pacific Coast are diverse and productive ecosystems of high ecological, cultural, and economic value. They have many stakeholders, are managed t

The estuaries of the U.S. Pacific Coast are diverse and productive ecosystems of high ecological, cultural, and economic value. They have many stakeholders, are managed to meet many different, often competing, objectives, and contend with environmental stressors from a variety of sources. Ocean acidification (OA) is one stressor expected to have widespread impacts on the Pacific coastal ecosystems. Recently, the West Coast Ocean Acidification & Hypoxia Science Panel recommended improved monitoring to assess biological impacts in the coastal ocean and estuaries. However, the current status and impacts of ocean acidification on West Coast estuaries are largely unknown. A workshop in October 2016 brought together scientists from throughout the West Coast of the United States, leading researchers on San Francisco Bay, the region’s largest estuary, and representatives from a variety of management agencies. The main objectives of the Workshop were to assess whether acidification is of concern in the Bay and to identify its potential impacts to beneficial uses, cost-effective monitoring strategies, and potential management actions. Although the Bay was the case study, the aim was to develop general guidance that could be applied to West Coast estuaries.

Monitoring of Drought Awareness from Google Trends: A Case Study of the 2011–17 California Drought

American Meteorological Society (AMS) | April 1st, 2019

Monitoring Program for the Santa Maria Valley Management Area

California Department of Water Resources (DWR) | April 11th, 2013

The terms and conditions of a Stipulation in the Santa Maria Valley Groundwater Basin Litigation passed down by the Superior Court of the State of California, County of

The terms and conditions of a Stipulation in the Santa Maria Valley Groundwater Basin Litigation passed down by the Superior Court of the State of California, County of Santa Clara, on June 30, 2005, are intended to “impose a physical solution establishing a legal and practical means for ensuring the Basin’s long-term sustainability.” Under the Stipulation, the groundwater, imported and developed water, and storage space of the Basin are to be managed in three management areas, including one for the Santa Maria Valley (SMVMA) (Figure 1). The management area is approximately 175 square miles in size encompassing the Santa Maria and Sisquoc Valleys, extending north to the Nipomo Mesa, east to the cliffs above the Santa Maria River and terraces along the Sisquoc River, south to the Casmalia and Solomon Hills, and west to the coast. According to the Stipulation, a monitoring program is to be established for each of the three management areas to collect and analyze data regarding water supply and demand such that the following objectives are met: 1) assessment of groundwater conditions, both levels and quality; 2) determination of land use, water requirements, and water supply; and 3) accounting of amounts and methods of disposition of water utilized. This monitoring program has been prepared to meet these objectives in the SMVMA. Also in accordance with the Stipulation, it is expected that the monitoring results will be utilized for preparation of annual reports on the SMVMA, including an assessment of whether conditions of severe water shortage are present. The monitoring program for the SMVMA, with minor revisions from October 2008, is described by individual element in the following section. Among other components, the monitoring program includes networks of historically monitored wells, stream gauges, and climatic stations. These monitoring points were selected based on publicly available information about their locations, characteristics, and historical data records with the intent of continuing those records as much as possible. It is recognized that, as implementation of the program proceeds, the inclusion of some network wells may be determined to be impractical or impossible due to problems of access or abandonment. Further, the reestablishment of inactive (or installation of new) wells, stream gauges and climatic stations will depend on interagency coordination, permitting procedures, and budgetary constraints. Thus, it is anticipated that the overall monitoring program will be incrementally implemented as practicalities like those mentioned above dictate. Similarly, it is expected that, with time, the program will undergo modification in response to various factors (e.g. replacing network wells abandoned in the future, revising well classifications by aquifer depth zone), while maintaining the overall goal of facilitating interpretation and reporting on water requirements, water supplies, and the state of groundwater conditions in the SMVMA.

Monitoring Special Study (MSS) Salinity Point Source and Ion Sampling CY 2022–2023

California Department of Water Resources (DWR) | August 15th, 2022

The interior southern Delta region of the San Francisco Estuary (SFE) has relatively higher seasonal-based salinity compared to other interior freshwater regions. Some of

The interior southern Delta region of the San Francisco Estuary (SFE) has relatively higher seasonal-based salinity compared to other interior freshwater regions. Some of this degradation in water quality in the interior southern Delta likely originates in upstream salt loading from agriculture drainage in the San Joaquin River prior to reaching the channels of Old River and Grant Line Canal. However, there is also measurable increases in salt loading within the channel networks of Old River at Head (OH1) east to lower Old River near Mountain House Creek (ORM) and the interconnected sloughs of Paradise and Sugar Cut in the region of Doughty Cut (Figure 1) (in-Delta agriculture drainage), as well as other naturally occurring (i.e., groundwater) sources and other non-point and point sources. The California Department of Water Resources (DWR) and U.S. Bureau of Reclamation (Reclamation), under the State Water Resources Control Board’s (State Water Board) Water Right Decision 1641 (D-1641), are assigned partial responsibility for meeting interior southern Delta water quality objectives each year at multiple compliance stations that measure specific conductance (EC) data continuously at 15-minute intervals.

Monitoring Strategies for Chemicals of Emerging Concern (CECs) in California’s Aquatic Ecosystems

California State Water Resources Control Board (SWRCB) | April 26th, 2012

Although thousands of substances can now be detected in the environment, a small percentage of known chemicals – approximately 200 -- are currently regulated and/or rou

Although thousands of substances can now be detected in the environment, a small percentage of known chemicals – approximately 200 -- are currently regulated and/or routinely monitored in California receiving waters.  The much larger group of chemicals that remain largely unregulated and/or unmonitored in the aquatic environment, known as chemicals of emerging concern (CECs), may originate from a wide range of point and non-point sources. Upon discharge to receiving waters, CECs that are readily soluble in water will remain in the dissolved (aqueous) phase and provide a route of exposure to aquatic life. A smaller subset of CECs that are hydrophobic will associate with particles, where they may remain suspended in the water column or accumulate in sediments and ultimately in tissues of aquatic and terrestrial biota. The larger concern is that exposure to aqueous, sediment and tissue CECs may affect wildlife and humans. In response, the California Water Resources Control Board (State Water Board) in conjunction with the David and Lucile Packard Foundation and a group of stakeholder advisors tasked a group of leading scientists to address the issues associated with CECs in the State’s aquatic systems that receive discharge of treated municipal wastewater effluent and stormwater. The group was charged to identify potential sources and evaluate the fate and effects of CECs, and ultimately to provide guidance for developing monitoring programs that assess those chemicals with the highest potential to cause effects in the State’s receiving waters. Seven experts in chemistry, biochemistry, toxicology, chemical and risk assessment, engineering and coastal and marine environmental health science were convened as the CEC Ecosystems Panel (“Panel”) in October 2009. The Panel held six in?person meetings to formulate their approach and recommendations, while soliciting input from stakeholders and the public. This report provides the results from the Panel’s deliberations, including four products intended to assist the State in developing a monitoring process for CECs based on sound, up-to-date scientific principles.

Monitoring Well Destruction, Replacement, and New Installations at Various Locations Soquel, Capitola, and Aptos, CA

Soquel Creek Water District | June 14th, 2012

A total of six new monitoring wells and seven replacement monitoring wells were drilled and constructed, and 13 monitoring well destroyed between February 7 and April 26,

A total of six new monitoring wells and seven replacement monitoring wells were drilled and constructed, and 13 monitoring well destroyed between February 7 and April 26, 2012 for the Soquel Creek Water District (District). This work took place at six different locations in the Soquel-Aptos area. The work was accomplished in order to meet the basin management objectives of the Soquel-Aptos Groundwater Management Plan (Soquel Creek Water District and Central Water District, 2007) and recommendations made in the Water Year 2010 Annual Report and Review (HydroMetrics WRI, 2011). A summary of the work performed and monitoring well construction details at each of the six locations are provided below.