,This feature class is a vector file containing polygons that represent the flood control bypasses of the Sacramento and San Joaquin Rivers. Bypasses convey excess flood waters from rivers and streams onto designated lands to reduce flood risks to populated areas. It combines polygons the capacity coverage (which follows CLD Levee centerlines) from GEI Consutlants, Flood Project Inspection and Integrity Branch (FPIIB) capacity coverage, digitized areas from 2005 NAIP (Butte Basin and Butte Slough), and polygons digitized by Michael Ward -- SJR Bypasses (Eastside, Chowchilla Canal, and Mariposa).,20141015: The parent bypass layer was compiled by DWR, Northern Region Office using data supplied by various sources, as stated in the metadata, which is for display purposes in maps. The Yolo Bypass polygon has been substituted for the polygon developed by MWH Global Inc. in 2012 and was modified to more closely match previously reported acreages. The primary modifications are: 1) Removal of the Sacramento River Deep Water Channel 2) The west side of the bypass was modified to match the Central Valley Flood Protection Plan (CVFPP) economic impact dated 20110826 areas from Putah Creek to the end of the western levee. This layer was used in the CVFPP 2017 Update.,20210107: Prospect Island was added from parent file Delta_Islands_20140616.shp. It is not a legal boundary and is for representation only.,

Database of historical levee breaks in the California Central Valley, particularly in the Sacramento-San Joaquin Delta. Dataset was built over years based on a variety of sources and ongoing incidents during the period in which the dataset steward was in the Delta Levees Program. Consequently, it primarily consists of levee failures in the Delta, plus additional levee failures mapped by the State Office of Emergency Services for the 1983, 1986, 1995, and 1997 floods throughout the Central Valley. It is useful to know where historic breaks occurred for ongoing purposes requiring geotechnical and engineering information. The associated data are considered DWR enterprise GIS data, which meet all appropriate requirements of the DWR Spatial Data Standards, specifically the DWR Spatial Data Standard version 3.1, dated September 11, 2019. DWR makes no warranties or guarantees —either expressed or implied — as to the completeness, accuracy, or correctness of the data. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data. Comments, problems, improvements, updates, or suggestions should be forwarded to gis@water.ca.gov as available and appropriate.

,Following adoption of the 2012 Central Valley Flood Protection Plan (2012 CVFPP), DWR funded six regionally-led Regional Flood Management Plans (RFMPs) that describe local and regional flood management priorities and challenges. These RFMPs also identify potential funding mechanisms and site-specific improvement needs.,The Regional Flood Management Planning Regions (RFMP) boundaries were created from the 2013 Levee Flood Protection Zones (LFPZs). Waterways were filled in and the boundaries were broken into the six planning areas by GEI Consultants Inc.,This is the second generation of study areas after the 2012 CVFPP for more specific regional planning efforts with local agencies.,

This dataset is a compilation of ownership rights represented as parcels owned by the Sacramento & San Joaquin Drainage District of the State of California (SSJDD), under the authority of the Central Valley Flood Protection Board (CVFPB).

Largely supported by the Interagency Ecological Program (IEP), California Department of Water Resources (DWR) has operated a fish monitoring program in the Yolo Bypass, a seasonal floodplain and tidal slough, since 1998. The objectives of the Yolo Bypass Fish Monitoring Program (YBFMP) are to: 1. Collect baseline data on water quality, chlorophyll, lower trophic level biota, and fish in the Yolo Bypass to monitor spatial and temporal changes in trends and abundance. 2. Analyze and communicate Yolo Bypass data with interested parties and the scientific and management communities to address pertinent management-related questions. 3. Provide technical expertise on Yolo Bypass aquatic ecology and monitoring and sampling methods. The YBFMP operates a rotary screw trap and fyke trap and conducts biweekly beach seine and lower trophic surveys in addition to maintaining water quality instrumentation in the bypass. The YBFMP informs the restoration actions that are mandated or recommended in these plans and provides critical baseline data on the ecology of the bypass and how it interacts with the broader San Francisco Estuary. YBFMP’s data is often accompanied by information on whether the Yolo Bypass is inundated, as water quality, and species composition and abundance can be greatly altered during inundation. This dataset was created to consistently estimate inundation over time. Estimating inundation in the Yolo Bypass is usually done by referencing stage height in the Sacramento River at Fremont Weir. Stage height is the water level of the river. Fremont Weir is upstream of the Yolo Bypass and when Fremont Weir overtops, or reaches its monitoring stage, the Yolo Bypass is considered inundated. This dataset is originally published on EDI and linked to this CNRA open data portal.

This dataset is a compilation of ownership rights represented as parcels owned by the Sacramento & San Joaquin Drainage District of the State of California (SSJDD), under the authority of the Central Valley Flood Protection Board (CVFPB).

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Department of Water Resources Hydrologic Region boundaries derived from i03_DAU_county_cnty2018.

In California, there are a variety of political entities that are granted self-taxation powers under various California codes in order to perform the basic goal of flood management within an area. This dataset compiles many of the various datasets together to provide the information in one location. It also includes districts that are no longer active political/management entities for archival or historical purposes. The primary type of flood agency in California are known as reclamation districts, and so represent the majority of the records in this database. The quality of the boundary accuracy is highly variable, due to a variety of reasons, including the fact that the original legal boundaries are frequently tied to Swamp Land Survey boundaries that themselves are poorly located by modern mapping standards. This set of boundary delineations represents the latest in a series of nearly 20 significant revisions primarily by DWR Delta Levees Program between 2000-2017 to a dataset first produced by Office of Emergency Services during the 1997 floods. The accuracy and completeness of the data are therefore higher in the Delta than elsewhere. The Division of Flood Management then stored the boundaries in their levee geodatabase that feeds the web mapping application known as FERIX. To produce this final dataset, in 2018 the Division of Engineering Geodetic Branch merged the data used by FERIX, along with other datasets used by the Delta Levees Program, and normalized the attribute table.

This feature class represents inundated area for the Coast Fork of the Willamette River, the Row River and Silk Creek (west of Cottage Grove, OR) for eight different flows at the gage Willamette River at Goshen, OR (USGS 14157500). The flows are 12,000; 15,000; 21,450; 27,900; 33,900; 39,900; 46,800 and 62,300 cubic feet per second (cfs). These flows correspond to gage heights of 11.8, 13.2, 15.1, 16.3, 17.2, 17.9, 18.6 and 19.8 feet, respectively. The domain of the model is as follows: Row River from Dorena dam to the confluence with the Coast Fork; Coast Fork from Cottage Grove dam to the confluence with the Middle Fork; Silk Creek from River Mile 1.7 to the confluence with the Coast Fork. The basis for these features is the Willamette Flood Insurance Study – Phase One (2013). The hydraulics and hydrology for the FIS were reused in the production of these polygons; the reports and information associated with the FIS are applicable to this product. The Digital Elevation Model (DEM) utilized for the Willamette FIS submittal was produced by combining multiple overlapping topographic surveys for the Middle Fork and Coast Fork of the Willamette River. This DEM was created from four sources: LiDAR of the Springfield area that was flown in 2008, LiDAR of Silk Creek that was flown in 2011, LiDAR of Fall Creek that was flown in 2012, and photogrammetry of the Middle Fork and Coast Fork of the Willamette River that was flown in 2004. In areas where no high-resolution elevation data were available, USGS National Elevation Dataset (NED) data were used to supplement the DEM. The shapefiles Hi_Res_Extents.shp and Low_Res_Extents.shp define the limits of these areas. The horizontal datum of the DEM is NAD 1983 State Plane-Oregon South HARN with units of International Feet (NAD83). The vertical datum of the elevation model is NAVD 1988 with units of international feet (NAVD-88). In addition, some areas show surveyed bathymetry within the channel. These can be noted by the sharp increase in apparent depth, creating a stripe across the depth grid when compared to the LiDAR data, which represents the water surface elevation at the time of the aerial data collection. Bridge decks are generally removed from DEMs as standard practice. Therefore, these features may be shown as inundated when they are not. An effort to clip flood extents on bridge decks was made, but judgement should be used when estimating the usefulness of a bridge during flood flow. Comparing the bridge to the surrounding ground can be more informative in this respect than simply looking at the bridge itself. The features and depth grids stop as the Coast Fork approaches the Middle Fork on the northern end of the reach.