Recent Projects

Project Title: Climate Change Adaptation in the San Joaquin Valley
National Institute of Food and Agriculture (USDA)
February 2016 – Present

Almond Irrigation

Flood irrigation of almond trees in California’s central valley

Systech is collaborating with academic and private partners to evaluate strategies for agricultural adaptation to future water resources constraints in the San Joaquin Valley, CA resulting from climate change. The project will integrate multiple models, each of which focuses on specific aspects of the system, including high elevation snowmelt, reservoir operations, surface water hydrology, groundwater hydrology, water quality, agricultural practice and response, and economics. The resulting integrated modeling framework will be applied to assess multiple scenarios of adaptation to future water, agriculture, and climate pressures. Systech will be integrating the San Joaquin River WARMF into the modeling framework to simulate changes in important water quality constituents for agriculture in the San Joaquin Valley.


Project Title: Lower Catawba Basin Nutrient TMDL
Client: South Carolina Department of Health and Environmental Control (SC DHEC)
November 2012 – Present

Catawba WARMFThe Catawba River, originating in the Blue Ridge Mountains of North Carolina, is controlled by a system of 14 major dams and 11 major lakes along its path to Lake Wateree, South Carolina. Many river reaches and lakes in the basin are listed as impaired by the USEPA for parameters including ecological/biological integrity, fecal coliform bacteria, mercury, eutrophication, turbidity, metals, and nutrients. One of the first applications of the Watershed Analysis Risk Management Framework (WARMF) was developed for the Catawba River Basin, originally set-up by Systech in parallel with their initial WARMF model development in the late 90s/early 2000s. This initial version of the Catawba River WARMF application, funded largely by Duke Energy via the Electric Power Research Institute (EPRI), was used for watershed stewardship studies, sediment BMP assessments, hydropower relicensing, and TMDL analyses (Copper and Phosphorus). Some features of WARMF, such as the capability to adjust reservoir elevation based on observed values, were developed specifically for the Catawba application.

Taking advantage of the existence of the Catawba River WARMF application, Systech was contracted in 2011 to assist the South Carolina Department of Health and Environmental Control (SC DHEC) to update and recalibrate the model. The model update was part of efforts to prepare for the development of nutrient TMDLs for the South Carolina Catawba River reservoirs. Systech extended the database through 2012 (including inputs of meteorology, air quality, point sources, diversions, reservoir releases, and measured flow and water quality), updated land use, delineated urban (MS4) areas, and recalibrated the lower portion of the basin (including 4 of the 11 lakes) for flow, temperature, sediment, nutrients and phytoplankton. The model is currently being used by SC DHEC to simulate the water quality impact of varying point and nonpoint source load reductions in the reservoirs.

Project Title: San Joaquin River Salinity Forecasting
United States Bureau of Reclamation (USBR)
September 2013 – Present


San Joaquin River at Crow’s Landing

The San Joaquin River in the California’s Central Valley is a crucial source of irrigation for one of the most productive agricultural regions in the world, as well as an important wildlife corridor. The water quality of the river, however, is severely impacted by overuse and agricultural drainage. The stretch of river near Vernalis, CA has a Total Maximum Daily Load (TMDL) in effect which requires that electrical conductivity (EC) be less than specified limits to protect irrigation use in the south Delta. To meet the water quality objective, dischargers in the San Joaquin River watershed must either accept strict limits to their salt load or participate in a real-time discharge management program.


WARMF Manager Module

Systech is providing technical support to the US Bureau of Reclamation, which provides irrigation water for much of the San Joaquin Valley and is leading the real-time salinity management program. This project aims to link real-time flow and salinity monitoring, forecast modeling, and stakeholder participation to strategically time high salinity discharges to the river and take advantage of assimilative capacity. The San Joaquin River WARMF model, developed by Systech, is used to perform short-term forecast simulations of flow and salinity. As part of this project, Systech created and upgraded features of WARMF to facilitate and improve the forecast simulations, including a Manager Module, improved wetlands simulations, and unique longitudinal loading output.

34 North, Systech’s subcontractor, built the San Joaquin River Regional Water Quality Monitoring web portal (, which collects real-time monitoring data, displays data and model results, and facilitates stakeholder communication and interaction.

Project Title: Water Saving Technologies and Strategies for Sectors Other than Electric Power
Client: Electric Power Research Institute (EPRI)
July 2014 – December 2015

Sprinkler irrigation

Sprinkler irrigation

Systech performed a research investigation for the Electric Power Research Institute (EPRI) to assess water saving technology in non-electric power sectors. The research focused on identifying the technologies available to decision makers for reducing water consumption within the agricultural, domestic, and industrial water use sectors. A thorough review of the scientific literature was conducted to identify all the water saving technologies that are relevant to these sectors. When feasible, example calculations were made to illustrate the water conservation potential of the available water saving technologies. An extensive report and presentation were delivered to EPRI outlining the results, outlining water saving technologies available within each water use sector, the advantages and disadvantages of each technology, and a qualitative estimate (e.g. low, medium, high) of the water conservation potential relative to the other technologies that are available. These results are aimed to help guide EPRI members in identifying potential water saving technology for their own operations.

Project Title: Sacramento-San Joaquin Delta Turbidity Forecasting
Client: Metropolitan Water District of Southern California
September 2010 – May 2013

Turbidity ForecastingThe Sacramento – San Joaquin River Delta is an important source of drinking water for central and southern California. It is also critical habitat for the endangered and endemic Delta Smelt, which mainly inhabits the estuary mixing zone but migrates upstream to freshwater during its spawning season. High turbidity conditions are believed to be an indicator of when Delta Smelt are more likely to be present in the central and south Delta where water supply pumps are located. The Delta’s pumping plant operations are regulated to protect adult Delta Smelt.

To better optimize their pumping operations for both environmental and water supply objectives, the Metropolitan Water District (MWD) of Southern California contracted with Systech and Resource Management Associates (RMA) to develop a turbidity forecast system for the Delta. Since Delta conditions are driven by upstream watershed processes, the system needed to include forecasts of turbidity loads entering the Delta from tributaries as well as in-Delta fate and transport. Systech and RMA collaborated to establish a method that utilizes the Watershed Analysis Risk Management Framework (WARMF) model to supply the RMA11 Delta Turbidity model with upstream boundary conditions. Results of the two-year collaboration showed that these two models can be combined to effectively forecast turbidity fate and transport in the Delta, providing the information necessary to optimize pumping plant operations for both environmental and water supply objectives.

Project Title: San Juan River Mercury, Selenium and Arsenic Transport and Bioaccumulation
Client: Electric Power Research Institute (EPRI)
August 2012 – December 2015

SanJuan WARMFThe San Juan River in the Four Corners region from Farmington, NM downstream to Lake Powell is impacted by trace metals contamination. This stretch of the river is also critical habitat for the endangered Colorado Pikeminnow and Razorback Sucker, and fish tissue samples collected from these species in this watershed exhibit elevated concentrations of trace metals. Trace metals, such as mercury, selenium, and arsenic are introduced to the aquatic ecosystem by atmospheric deposition, mineral weathering, mining, and other sources. Atmospheric deposition results from both natural and anthropogenic emissions from local, regional and global origins. Identifying the relative importance of different terrestrial and atmospheric sources is critical to designing strategies of source control or site mitigation. The benefit of potential control measures is difficult to assess directly due to the large storage capacity of watershed soils for adsorbing trace metals, such as mercury. Changes in the watershed due to changes in atmospheric inputs may take many years or decades to become evident.

In 2012, Systech was hired by the Electric Power Research Institute (EPRI) to study the long-term effect of projected changes in atmospheric deposition of trace metals on surface water concentrations and fish tissue concentrations in the San Juan River. Systech built and calibrated a WARMF model of the San Juan watershed, extending from the headwaters in Southern Colorado to Lake Powell. Systech engineers modified the WARMF simulation algorithms to simulate mercury, selenium and arsenic deposition, transport through the environment, chemical transformation, and bioaccumulation/biomagnification processes. Systech engineers collaborated with the consulting firm Ramboll Environ, Inc. to link the San Juan WARMF model to the CMAQ-APT air model, which provided spatially explicit values of wet and dry atmospheric deposition of the trace metal species over the watershed for six deposition scenarios (a base case plus five plausible scenarios of local coal-fired power plant emissions and global emissions from Asia). The watershed response to the six deposition scenarios was simulated by WARMF for the period of 1990-2074. Comparisons between scenarios’ results provided EPRI and its clients with guidance on the potential long-term effectiveness (or lack thereof) of making costly changes to power plant operations in order to reduce trace metal surface water and fish tissue concentrations in the San Juan River.

Project Title: Salinity and Organic Carbon Source Assessment for California Drinking Water Supplies
Client: California Urban Water Agencies (CUWA)
2008 – 2011

SJR Sac DeltaThe Sacramento-San Joaquin River Delta is a major source of drinking water for California. The Delta receives inflows and pollutant loads from the Sacramento River and San Joaquin River, several smaller tributaries, and tidal mixing with the ocean. Salinity and organic carbon are of primary concern at drinking water intakes. Due to the expense of water filtration and chemical water purification, source water protection is the most cost-effective way to keep these and other pollutants out of drinking water. Protection of sources involves assessment of the contribution of various sources to organic carbon and salinity concentrations at the intakes, and is best accomplished through numerical modeling.

In 2008, Systech began work for the California Urban Water Agencies (CUWA) to apply WARMF for the Sacramento and San Joaquin watersheds to identify and quantify urban, industrial, agricultural and natural sources of salts and organic carbon delivered to drinking water intakes in the Sacramento-San Joaquin River Delta. The existing San Joaquin River model was upgraded and a new WARMF application for the Sacramento River was created. Sources of salinity and organic carbon in both watersheds were summarized for existing and future conditions. WARMF provided time series of flow and water quality for use as inputs by the DSM2 estuary model. Findings from this project were used to inform drinking water policy development in the central valley of California.

Project Title: Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) Pilot Studies
Client: Central Valley Salinity Coalition
2009 – 2010

CVSALTS Pilot StudiesElevated salt and nitrate concentrations are an ongoing water quality issue through much of California’s Central Valley Region. Because of this, the Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) initiative was started in 2006 to find collaborative solutions to the salt problem in the Central Valley. In 2009, CV-SALTS began a pilot study to quantify significant sources of salt and nitrate in three selected central watersheds – the Tule River basin, the east side of the San Joaquin River near Modesto, and Yolo County. The goal of the pilot study was to develop and test methodologies and evaluate the feasibility of wider application. Systech worked with CV-SALTS and several partners on the pilot study. Systech created or modified WARMF applications for the three study watersheds, linked WARMF simulations to existing groundwater models (CVHM and MODFLOW), and quantified sources of salinity and nitrate in each watershed. Results provided guidance for future salt and nitrate reduction efforts in the central valley.