Nigel W T Quinn

In San Joaquin Valley, over 90 % of the seasonal wetlands existed in 1890 have disappeared due to water diversions and withdrawals upstream for crop irrigation. The Kesterson ecological crisis was a fortuitous event in that it gave acute recognition to a chronic problem that began when selenium-latent drainage water began being used as a wetland water supply. In light of the discovery, how should salinity and Se in drainage water in the San Joaquin and Tulare Lake Basins be managed to support wetlands and wildlife?

The use of Geographic Information Systems (GIS) and remote sensing technologies for the development of water quality management programs and for post-implementation assessments has increased dramatically in the past decade. This increase in adoption has been made more accessible through the interfaces of many popular software tools used in the regulation and assessment of water quality. Customized applications of these tools will increase, as ease of access and affordability of directly monitored and remotely sensed datasets improve over time. Concurrently, there is a need for inclusive participatory engagement with stakeholders to achieve solutions to current watershed management challenges. This paper explores the potential of these GIS and remote sensing datasets, tools, models, and immersive engagement technologies from other domains, for improving public participation and stakeholder engagement throughout the watershed planning process. To do so, an initial review is presented ...

Environmental problems and production losses associated with irrigated agriculture, such as salinity, degradation of receiving waters, such as rivers, and deep percolation of saline water to aquifers, highlight water-quality concerns that require a paradigm shift in resource-management policy. New tools are needed to assist environmental managers in developing sustainable solutions to these problems, given the nonpoint source nature of salt loads to surface water and groundwater from irrigated agriculture. Equity issues arise in distributing responsibility and costs to the generators of this source of pollution. This paper describes an alternative approach to salt regulation and control using the concept of “Real-Time Water Quality management”. The approach relies on a continually updateable WARMF (Watershed Analysis Risk Management Framework) forecasting model to provide daily estimates of salt load assimilative capacity in the San Joaquin River and assessments of compliance with s...

In this synthesis, we assess present research and anticipate future development needs in modeling water quality in watersheds. We first discuss areas of potential improvement in the representation of freshwater systems pertaining to water quality, including representation of environmental interfaces, in‐stream water quality and process interactions, soil health and land management, and (peri‐)urban areas. In addition, we provide insights into the contemporary challenges in the practices of watershed water quality modeling, including quality control of monitoring data, model parameterization and calibration, uncertainty management, scale mismatches, and provisioning of modeling tools. Finally, we make three recommendations to provide a path forward for improving watershed water quality modeling science, infrastructure, and practices. These include building stronger collaborations between experimentalists and modelers, bridging gaps between modelers and stakeholders, and cultivating a...

In the domain of environmental sciences, measurement is the process that maps some observed phenomenon to a formal measurement value, the latter being the result of a measurement process. The measurement process relies on data representing inherently informal physical quantities of possibly continuously changing phenomena. These measurement processes and their measurement values are plagued with quality issues because of the inherent imprecision of the source data and interpretations made within the process itself. Many of these quality issues may be parameterised and provided as metadata of the measurement value, e.g. precision, resolution, trustworthiness. Of these, the trustworthiness quality parameter is evaluated by the consumer of the measurement value; this evaluation is a subjective perception of the level of momentary reliance justifiably placed on the measurement value and possible quality parameters. The consumer’s trustworthiness parameter builds up from the past evaluat...

Model selection for water quality forecasting depends on many factors including analyst expertise and cost, stakeholder involvement and expected performance. Water quality forecasting in arid river basins is especially challenging given the importance of protecting beneficial uses in these environments and the livelihood of agricultural communities. In the agriculture-dominated San Joaquin River Basin of California, real-time salinity management (RTSM) is a state-sanctioned program that helps to maximize allowable salt export while protecting existing basin beneficial uses of water supply. The RTSM strategy supplants the federal total maximum daily load (TMDL) approach that could impose fines associated with exceedances of monthly and annual salt load allocations of up to $1 million per year based on average year hydrology and salt load export limits. The essential components of the current program include the establishment of telemetered sensor networks, a web-based information sys...

nted rate and scale. human health, have re essential tools to stakeholder mental explain data, as well as of interest where the integration of make the vital step nts and identify key er the CC BY-NC-ND nses/by-nc-nd/4.0/). assess effects of environmental factors on human and ecosystem health. Applications include, but are not limited to, themodelling of n, dispersion and (e.g., Vieno et al., ts (e.g., Wu et al., ntification of hu-, 1993; MacIntosh et al., 1995), the risks and public health burdens from exposures to environmental pollutants (e.g., Lim et al., 2012; Schlink et al., 2010), the dynamics of biomarkers in relation to drugs and path-ogens, and the efficacy of efforts to control the consequences of these processes on human health (e.g., May et al., 2008; Wu et al., 2014b), and the quantification of stakeholder mental models for optimal decision making (Wood et al., 2012; Voinov et al., 2014; Boschetti, 2015). Models have important uses in examining the

Grassland Bypass Project Annual Report 56 Introduction The purpose of this chapter is to compare the loads of salt discharged by the Grassland Bypass Project (GBP) with loads that might exist in the absence of the Project. This comparison uses flow and salinity data for Stations B, ...

Water supply, reallocation and conjunctive use options, within the San Joaquin and Tulare basins of the Central Valley of California, are being considered by Federal and State Planning agencies as a means of protecting fish and wildlife resources from adverse impacts associated with agricultural drainage water. These actions will likely be coupled with direct measures aimed at encouraging source control of agricultural drainage, such as the establishment of maximum drainage discharge volumes and/or qualities (i.e., loads, and/or contaminant concentrations), or the establishment of water quality standards for receiving waters. This paper presents a brief account of the groundwater model which has been developed for water supply analysis in the region.

Environmental policies to address water quality impairments in the San Joaquin River of California have focused on the reduction of salinity and selenium-contaminated subsurface agricultural drainage loads from westside sources. On 31 December 2019, all of the agricultural drainage from a 44,000 ha subarea on the western side of the San Joaquin River basin was curtailed. This policy requires the on-site disposal of all of the agricultural drainage water in perpetuity, except during flooding events, when emergency drainage to the River is sanctioned. The reuse of this saline agricultural drainage water to irrigate forage crops, such as ‘Jose’ tall wheatgrass and alfalfa, in a 2428 ha reuse facility provides an economic return on this pollutant disposal option. Irrigation with brackish water requires careful management to prevent salt accumulation in the crop root zone, which can impact forage yields. The objective of this study was to optimize the sustainability of this reuse facilit...

This paper provides a chronology and overview of events and policy initiatives aimed at addressing irrigation sustainability issues in the San Joaquin River Basin (SJRB) of California. Although the SJRB was selected in this case study, many of the same resource management issues are being played out in arid, agricultural regions around the world. The first part of this paper provides an introduction to some of the early issues impacting the expansion of irrigated agriculture primarily on the west side of the San Joaquin Valley and the policy and capital investments that were used to address salinity impairments to the use of the San Joaquin River (SJR) as an irrigation water supply. Irrigated agriculture requires large quantities of water if it is to be sustained, as well as supply water of adequate quality for the crop being grown. The second part of the paper addresses these supply issues and a period of excessive groundwater pumping that resulted in widespread land subsidence. A ...

ABSTRACT Background/Question/Methods As part of a larger study investigating algal dynamics in the tidally-influenced San Joaquin River (SJR) of the Sacramento – San Joaquin Delta Estuary, algal and zooplankton abundances were analyzed during periods of zero, moderate, and high net flows into the Stockton Deep Water Ship Channel (DWSC) from June 2007 through June 2008. High flow conditions resulted from reservoir releases or the installation of the Head of Old River Barrier (HORB) during October and early November 2007, which provides increased SJR flow to enhance fish habitat. The purpose of this study is to elucidate planktonic behavior subject to flow and seasonal variation. The study reach consisted of a 25-mile segment of the SJR including the dredged DWSC, which was sampled at approximately two mile intervals over two high and low slack tides. Monitoring was performed at intervals ranging from one to five weeks. Chlorophyll a and pheophytin a were quantified as surrogates of phytoplankton abundance and physiological condition. Zooplankton population density and biomass were determined by microscopic examination of mid-depth collected samples. Results/Conclusions Spatial clusters of high zooplankton populations are strongly influenced by flow, with higher flows pushing zooplankton further downstream into the forty-foot deep DWSC; lower flows allow populations to develop further upstream in the shallower reaches of the SJR. Under moderate flows zooplankton populations develop in an intermediate location, where the shallow SJR enters the deeper DWSC. High flow drove zooplankton density into the DWSC during fall 2007, where they remained until June 2008, once flows subsided. During net zero flows of July and August 2007, zooplankton proliferated upstream, with algal concentrations declining drastically as zooplankton concentrations increased. Throughout the study reach in general, algal and zooplankton populations were negatively correlated under moderate flows and warmer weather. With higher flows, which generally occurred during cooler months, population abundance of both algae and zooplankton were low with no clear abundance pattern. The highest algal concentrations were observed in the uppermost study reach due to favorable light conditions associated with shallow river depths and low zooplankton populations. Spatial distributions of algae exhibit a large decline near the SJR/DWSC transition, the specific location being flow dependent. Algal loss at this transition is likely caused by zooplankton grazing and/or depth-induced light-reduction.