The Hydrology Section has responsibility for a number of activities, including the following:

1. Perform modeling studies to provide the peak flows and hydrographs used in District facility design projects.
2. Monitor storm rainfall and runoff, do forecast modeling, and advise the Sheriff’s Office of Emergency Services on the potential for flood damages in the County.
3. Install and maintain a hydrographic gage network to provide real-time data during storms and collect data for use in design studies. The data collected from our gages are made available to the public for their use through our website.
4. Perform sediment yield calculations, especially after fires.
5. Maintain and update manuals and reports describing our design procedures and hydrology programs.
6. Review Hydrology Studies submitted with permit applications and CEQA review packages.

Hydrology Data Available to the Public

The Historical Rainfall and Streamflow Data site contains finalized reports and preliminary data for the rain and stream gages and evaporation stations operated by VCWPD or in conjunction with the USGS or other agencies. Please read our Frequently Asked Questions file included on the data home page for detailed information about the data website and what it provides. The Current Storm Information page provides snapshots of real-time data collected by our gage network. These data provide current rainfall totals, stream gage plots, and weather information.

• Historical Rainfall and Streamflow Data
• Current Storm Information
• Email questions about data to hydrodata@ventura.org

Design Hydrology Methodology- Link to Manual and VCRat Programs

Please see the 2017 update of the VCWPD Hydrology Manual and our design hydrology programs through the above link.  In general, peak flows from urban and small undeveloped watersheds for use in channel design can be evaluated using our modified rational method and programs (VCRat2.64, TC Calculator). Peak flows and hydrographs for regional facility design can be evaluated using the calibrated S-Graph developed from 2005 storm data using HEC-HMS. Other peak flow design methods that have been used to evaluate floodplains include the results from flow frequency analyses and inserting design storm rainfall in continuous models such as HSPF. For information on these advanced methods, please contact the Hydrology Section at (805) 654-2069 or email your request to PWA.DesignHydrology@ventura.org.

Debris and Detention Basin Information

Information about the District’s Debris and Detention Basins can be obtained from the Manuals available on our Basin Manual Webpage.

Sediment/Debris Bulking Factors And Post-Fire Hydrology for Ventura County

Hydrography is the science that measures and describes the physical features of bodies of water and the land areas adjacent to those bodies of water. Historic record keeping is central to the efforts of the District’s Hydrography team. In particular, hydrographic work for the District centers on collecting data as reported via specialized equipment such as stream gages and rain gages using modern technology such as Bluetooth transmission and solar powered gages. Stormwaters in our channels are compared to normal stream water depth and stream water velocity. Weather patterns are tracked, gages are deployed, maintained, repaired, and upgraded. Photos are taken, cataloged, and stored. Years’ worth of data form a valuable resource to the District and to others who rely on such data to make informed decisions based on the trends evidenced by the Hydrographers’ work. Our Hydrogaphy team provides the hand’s on work in the field to keep our flood warning system operational.  The Hydrography team is headed up Ron Marotto.

A great example of a historic storm damages photo from our library:

Damages caused by the February 1969 floods at Ventura Marina and Sewage Treatment Plant near Olivas Golf Course

The Watershed Protection District Information Technology Section is responsible for a range of technology related duties within the District:

GIS (Geographic Information Systems): GIS is a big part of how we do business nowadays.  Spatial data is created, catalogued, maintained, used Districtwide throughout our Agency and other County offices for static and interactive maps.  Our District spatial data is often disseminated to requesting parties.

Information Technology Assistance for WPD Staff:  We facilitate the acquisition and the surplus of technology related materials such as computers, monitors, software, database systems.  We also assist by providing web site development and maintenance, digital resource maintenance and similar systems. To request spatial data from our District: email PWA.HydroData@ventura.org

Assessments: Our Operations and Maintenance Division depends on our annual assessments via the tax bills to help fund ongoing maintenance of our 200 plus channel miles. The property related fees are known as Benefit Assessments.

For questions about District’s annual assessments or for spatial data you may call (805) 645-1383.