Submittals to the Regional Water Boards

Hydromodification Management (HM) Applicability Map

(New!) View the CCCWP 2023 HM Applicability Map, Web Application Format (CCCWP.maps.arcgis.com) (approved February 1, 2024).  The CCCWP 2023 HM Applicability Map should be used for rapid initial determination of whether location-based HM requirements apply to proposed land development projects in jurisdictions across Contra Costa County.  This web mapping application can be used by municipal staff, applicants for development project approvals, and the public.  Further information and the final resources are provided on Stormwater C.3 Guidebook webpage.

  

Important Note: The draft HM Applicability Map documents below have been formally approved by the San Francisco Bay Regional Water Quality Control Board (SFBRWQCB) Executive Officer (EO) as of February 1, 2024.  These documents were submitted to SFBRWQCB as part of 2022-2023 Annual Reporting requirements.  

• Submittal Letter (PDF) - Letter to Eileen White, SFBRWQCB, from Rinta Perkins, CCCWP.  September 1, 2023.  Submittal of 2023 Draft HM Applicability Map for Contra Costa County.
• Attachment A: CCCWP 2023 Draft HM Applicability Map (PDF) -- Draft map of Contra Costa County that designates all county areas within HM Applicable and HM Exempt categories per the MRP 3.0 permit language designations.  A link to a draft 2023 web mapping application with the same information was provided as well.  
• 2017 HM Applicability Mapping Methodology Technical Memorandum (PDF) -- This mapping methodology technical memorandum, which was not approved by the EO, is provided for background information and context.
• 2023 Addendum to the 2017 HM Applicability Map Methodology (PDF) -- This addendum details the data sources and methods used to update the 2017 map.  

 

(Archived) Hydrograph Modification Management Plan

Note: As of December 2022, CCCWP decided to adopt the Bay Area Hydrology Model (BAHM), and has worked with Clear Creek Solutions to incorporate Contra Costa rainfall data into the model.  Further information and resources are provided on Stormwater C.3 Guidebook webpage.

 

(Archived) Hydromodification Management Submittals (2007-2017)

• Hydromodification Technical Report (PDF), Municipal Regional Permit Provision C.3.g.vi.(2), September 29, 2017
• Letter regarding Implementation of Hydromodification Management Requirements in the Forthcoming Reissued Municipal Regional Permit (PDF), Municipal Regional Permit Attachment C, April 1, 2014
• IMP Monitoring Report (PDF), IMP Model Calibration and Validation Project, Municipal Regional Permit Attachment C, September 15, 2013
• July 2, 2007 submittal (PDF) of information to Water Board staff pursuant to Section V of Attachment A to Order R2-2006-0050.

(Archived) Hydrograph Modification Management Plan Submittals (2004-2005)

• Hydrograph Modification Management Plan Work Plan (PDF) 
  (Provision C.3.f, May 12, 2004)
• Draft Hydrograph Modification Management Plan Progress Report (PDF) 
  (Provision C.3.f, November 15, 2004)
• Final Hydrograph Modification Management Plan (HMP) (PDF), including all attachments (Provision C.3.f, May 15, 2005, minor corrections made April 19, 2006)

(Archived) Appendix B to Attachment 4: Sample Stream Stability Handbook Sheets

• Site #32: Marsh Creek (PDF)
• Site #37: Marsh Creek (PDF)
• Site #38: Marsh Creek (PDF)
• Site #43: Briones Valley (PDF)
• Site #56: Pinole Creek Tributary (PDF)
• Site #58: Reliez Creek (PDF)
• Site #59: Upper Reliez Creek (PDF)
• Site #60: Reliez Creek (PDF)
• Site #62: Pinole Creek at Amber Schwarz Park (PDF)
• Site #64: Pinole Creek (PDF)
• Site #65: Pinole Creek (PDF)
• Site #74: Briones Headwaters (PDF)
• Site #75: Marsh Creek Headwaters (PDF) 
• HMP Attachment 5: Timeline of HMP Preparation and Interaction with Water Board Staff (PDF)
• HMP Attachment 6: Response to Water Board Staff Comments (PDF) on the November 15, 2004 Draft HMP Progress Report

Other Submittals to the Regional Water Quality Control Boards

• Vector Control Plan (PDF) (June 1, 2004)