WCB Grant 2023114: Lower Los Angeles River Restoration and Access: Data includes one (1) year of water quality analysis to inform the design and serve as a baseline for restoration efforts. Two (2) sampling locations (Imperial Hwy. and Del Amo Blvd.) with both laboratory and field analysis for relevant WQ constituents. Data collected from two (2) locations over the course of one year to characterize both organic and inorganic indicators of water quality in the lower Los Angeles River. Data includes analytes targeted by laboratory analysis (sulfate, chloride, metals, etc.) and field measurement where appropriate (Temperature, pH, Electrical conductivity, Dissolved Oxygen, etc.) This data and metadata were submitted by California Department of Fish and Wildlife (CDFW) Staff though the Data Management Plan (DMP) framework with the id: DMP000719. For more information, please visit https://wildlife.ca.gov/Data/Sci-Data.

WCB Grant 2023114: Lower Los Angeles River Restoration and Access: Data includes one (1) year of temperature analysis to inform the design and serve as a baseline for restoration efforts. Two (2) sampling locations (Imperial Hwy. and Del Amo Blvd.) with direct measurement of water temperatures recorded from submerged data loggers over that time period. Data collected from two (2) locations over the course of one (1) year to capture seasonal temperature variation in the lower Los Angeles River. Data was collected from TidbiT data loggers that were kept submerged in the low-flow channel; both Imperial and Del Amo have bridge piers located in the middle of the low-flow channel, which makes year-round submersion of the temperature sensors possible. Data was collected in support of restoration efforts in the lower Los Angeles River, specifically the Lower Los Angeles River Restoration and Access (LLARRA) project. The project is in the planning and design phase (9/2025) and the collected data will serve to both guide restoration priorities going forward and serve as a baseline for projected beneficial outcomes of the project. The LLARRA project area is located between Paramount and Compton, roughly equidistant from the Imperial and Del Amo sampling locations. Those locations were selected for sampling due to mid-stream bridge piers that allowed sampling and measurement in relatively safe locations over the course of the work. Temperatures fluctuated seasonally, as expected, with colder temps dipping below 10 degrees C in the winter months, and reaching as high as 30 degrees C during the height of summer. These parameters provide a clear but challenging matrix for restoration priorities. This data and metadata were submitted by California Department of Fish and Wildlife (CDFW) Staff though the Data Management Plan (DMP) framework with the id: DMP000718. For more information, please visit https://wildlife.ca.gov/Data/Sci-Data.

WCB Grant 2023114: Lower Los Angeles River Restoration and Access: Data includes one (1) year of temperature analysis to inform the design and serve as a baseline for restoration efforts. Two (2) sampling locations (Imperial Hwy. and Del Amo Blvd.) with direct measurement of water temperatures recorded from submerged data loggers over that time period. Data collected from two (2) locations over the course of one (1) year to capture seasonal temperature variation in the lower Los Angeles River. Data was collected from TidbiT data loggers that were kept submerged in the low-flow channel; both Imperial and Del Amo have bridge piers located in the middle of the low-flow channel, which makes year-round submersion of the temperature sensors possible. Data was collected in support of restoration efforts in the lower Los Angeles River, specifically the Lower Los Angeles River Restoration and Access (LLARRA) project. The project is in the planning and design phase (9/2025) and the collected data will serve to both guide restoration priorities going forward and serve as a baseline for projected beneficial outcomes of the project. The LLARRA project area is located between Paramount and Compton, roughly equidistant from the Imperial and Del Amo sampling locations. Those locations were selected for sampling due to mid-stream bridge piers that allowed sampling and measurement in relatively safe locations over the course of the work. Temperatures fluctuated seasonally, as expected, with colder temps dipping below 10 degrees C in the winter months, and reaching as high as 30 degrees C during the height of summer. These parameters provide a clear but challenging matrix for restoration priorities. This data and metadata were submitted by California Department of Fish and Wildlife (CDFW) Staff though the Data Management Plan (DMP) framework with the id: DMP000718. For more information, please visit https://wildlife.ca.gov/Data/Sci-Data.

This layer includes 1,054 features indicating all assessed linear water bodies for the combined 2014 and 2016 Integrated Report. Under Section 303(d) of the Clean Water Act, states, territories and authorized tribes are required to develop a list of water quality limited segments. These waters on the list do not meet water quality standards, even after point sources of pollution have installed the minimum required levels of pollution control technology. The Clean Water Act requires that these jurisdictions establish priority rankings for water on the lists and develop action plans, called as Total Maximum Daily Loads (TMDL), to improve water quality. Every two years, the California State Water Resources Control Board submits a report on the State's water quality to the U.S. Environmental Protection Agency pursuant to Section 305(b) of the federal Clean Water Act. The Report provides water quality information to the general public and serves as the basis for U.S. EPA 's National Water Quality Inventory Report to Congress. This dataset includes all linear water body features in California assessed under Sections 303(d) and 305(b) of the Clean Water Act for the combined 2014 and 2016 Integrated Report listing cycle. Each water body is assigned a unique Water Body ID (WBID) number as well as selected associated information (water body name, Regional Water Quality Control Board number, etc.).

This layer includes 1,054 features indicating all assessed linear water bodies for the combined 2014 and 2016 Integrated Report. Under Section 303(d) of the Clean Water Act, states, territories and authorized tribes are required to develop a list of water quality limited segments. These waters on the list do not meet water quality standards, even after point sources of pollution have installed the minimum required levels of pollution control technology. The Clean Water Act requires that these jurisdictions establish priority rankings for water on the lists and develop action plans, called as Total Maximum Daily Loads (TMDL), to improve water quality. Every two years, the California State Water Resources Control Board submits a report on the State's water quality to the U.S. Environmental Protection Agency pursuant to Section 305(b) of the federal Clean Water Act. The Report provides water quality information to the general public and serves as the basis for U.S. EPA 's National Water Quality Inventory Report to Congress. This dataset includes all linear water body features in California assessed under Sections 303(d) and 305(b) of the Clean Water Act for the combined 2014 and 2016 Integrated Report listing cycle. Each water body is assigned a unique Water Body ID (WBID) number as well as selected associated information (water body name, Regional Water Quality Control Board number, etc.).

To manage the critically low 2021 water supply for beneficial uses, DWR installed the temporary emergency drought barrier (EDB) on West False River in the Sacramento–San Joaquin Delta (Delta), approximately 5 miles south of Rio Vista, California, in Contra Costa County in June 2021. To monitor the effectiveness and impacts of the EBD, a monitoring program was initiated to track changes in hydrodynamics, water quality, fish, harmful algal blooms, and aquatic weeds in the vicinity of the EDB. This data set includes all data collected as part of that monitoring program and subsets of ongoing monitoring programs that were used in the 2021 effectiveness report for the EDB.

This data release documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll . Data-collection cruises were conducted under three different environmental/flow conditions in August, September, and October 2018 that coincided with conditions prior to, during, and following a directed flow action or pulse of agricultural return water organized by the California Department of Water Resources and California Natural Resources Agency .

This data release documents the datasets and procedures used to update the Los Angeles Basin Watershed Model (LABWM) (Hevesi and Johnson, 2016) from INFIL3.0 (USGS, 2008a, 2008b) to INFIL4.0. The LABWM provides gridded monthly infiltration, evaporation, recharge, and runoff estimates for the Los Angeles region using the water balance recharge model, INFIL. INFIL is a grid-based, distributed-parameter, deterministic model that uses a daily time step to simulate the temporal and spatial distribution of the root-zone water balance, including net infiltration and potential recharge across the lower boundary of the root zone. INFIL3.0 was originally released and documented in 2008 (USGS, 2008a) and has been used and documented in several studies as the water-balance model used to develop spatially and temporally distributed estimates of recharge and runoff (Rewis and others, 2006; Hevesi and Christensen, 2015; Flint and Martin, 2012; Nishikawa and others, 2005; Hevesi and others, 2003; Paulinski, 2021a) including the LABWM (Hevesi and Johnson, 2016). The LABWM used the INFIL3.0 code with estimates of urban (landscape) irrigation to simulate the near-surface water balance from water years 1905 to 2014 for the Los Angeles Basin Watershed (Hevesi and Johnson, 2016) and to develop components of the recharge boundary condition for the Los Angeles Coastal Plain Groundwater Model (Reichard and others, 2003; Paulinski, 2021). Recently, there has been increased interest from stakeholders to update the Los Angeles Coastal Plain Groundwater Model (LACPGM) and thus there is a need to update the associated LABWM to include water years 2015 to 2020. To provide the updated water balance and recharge estimates, the INFIL3.0 code used in Hevesi and Johnson (2016) needed a modification to allow simulations to run past water year 2014. The modification made to update INFIL3.0 that result in the creation of INFIL4.0 involved increasing the array dimensions used for daily input variables, including precipitation, maximum and minimum air temperature, and surface water inflow, to allow for the increase in the total number of days in the extended simulation period (water years 1905 through 2020). The model archive included with this data release of the updated LABWM using INFIL4.0 includes the INFIL4.0 Fortran source code, the compiled INFIL4.0 executable file and related batch file, all input files needed to run the model from water year 1905 to 2020 for the 12 subdomains used in the LABWM, all simulation outputs for all subdomains, and a post-processing script (Monthmap). In addition to calculating the total potential recharge from contributing recharge areas outside the LACPGM boundary and recharge from interior LACPGM cells, the Monthmap script performs unit conversions (from millimeters per month to feet per day) and clips the output grid to match the areal extent of the LACPGM grid (Paulinski and others, 2021b).

California Aqueduct Subsidence Study. San Luis Field Division, and San Joaquin Field Division

California Aqueduct Subsidence Study. San Luis Field Division, and San Joaquin Field Division