i07_Delta_Levee_Habitat_Assessments

<p>These dataset acts as a historical inventory of the Delta Levee Program habitat assessments. Data was provided by the Delta Levees program within DWR. Data has now been compiled and re-formatted for the Atlas by DWR, DOE, Geomatics. This dataset contains habitat assessments from 1998 to 2022. Delta Levee Habitat Assessment information was gathered for the Delta Levees Program. California Department of Fish and Wildlife (CDFW), as part of the Delta Levees Program, must ensure that expenditure of Program funds for levee maintenance and improvement activities results in no net loss of riparian, fisheries, or wildlife habitat and provides net habitat improvement. CDFW measures the extent and types of these programmatic habitats along the levees by performing habitat assessments. Assessments were either performed by DFW or provided to DFW by a contractor. Chico State assisted in the mapping process of the assessments.In 2015, a pilot project was tested to compare assessment methods (GPS and Interpretive). This pilot project data will be stored in a separate feature class. The goal was “to evaluate three different mapping methods for the CDFW to use to ensure no net loss of habitat as required by the Delta Levees Program…[in order to assist] CDFW to evaluate alternative mapping methods that would increase the use and accuracy of habitat maps" as found in the Conclusion section of the report.. The pilot project data includes height, width, and species information for the habitat assessment. The most recent habitat assessments follow the GPS Mapping Method as described in section 3.3 of the report. These levee habitat assessments are not intended as exact areal habitat delineations and should not be used as such. Instead, these data were built as a tool to be provided for annual Subventions inspections conducted in the field by DWR, Dept of Fish &amp; Wildlife, Reclamation District staff, and RD-contracted engineers during annual field visits to determine eligibility of claims submitted by the RDs under the Delta Levees Program. The assessments would help to indicate the presence or absence of habitat areas prior to work that had been performed under the Program, and to support determination of any mitigation requirements resulting from such work. The classification system (freshwater marsh, shrub-scrub, shaded riverine aquatic, and riparian forest) was used with specific acreage mitigation ratios to determine a RD’s obligation for subsequent mitigation. The older style of mapping, with exaggerated polygons, was done on topographic maps prior to both aerial imagery and heads-up digitizing being available. Once aerial imagery and heads-up digitizing became available, using this system was employed for increased accuracy of habitat acreages and better representation of habitat on maps.The more modern assessments are closer to true delineations, but still should not be considered nor used exactly as such. In addition, “acreage” values should be considered as authoritative for potential mitigatable areas associated with any habitat polygon, rather than tabular values indicated by the Shape_Area field or any other GIS-derived area for a given polygon. Acreage values are more relevant than tabular values because they are more accurate being the data was collected more recently when compared to tabular values and the polygons are more accurate. However, CDFW does not solely rely on these acreages to determine impact amounts. Rather, it is one tool to help with annual inspections. 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 3.5, dated April 12, 2023. 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. This data set was not produced by DWR. Data were originally developed and supplied by California Fish and Wildlife and Chico State Geographic Information Center. Comments, problems, improvements, updates, or suggestions should be forwarded to <a href='mailto:[e-mail]' rel='nofollow ugc'>[e-mail]</a> as available and appropriate.</p>