Highway 299 – Green Point Sink Project Stormwater Inspection and Consulting

Soldier pile wall #2 during winter suspension
Excavation soils stockpile #1 with erosion control cover  and 	perimeter sediment barrier.
Prime Contractor: 
Period of Performance: 
April, 2013
Project Goals: 
  • Write the project Storm Water Pollution Prevention Plan (SWPPP).
  • Provide stormwater inspection and reporting services for construction activities
  • Ensure that compliance with the SWPPP, Construction General Permit (CGP) and 401 Water Quality Certification (401 Permit) is maintained. 
Project Description: 

This construction project includes the construction of two massive soldier pile retaining walls, installation and reconstruction of drainage systems, reconstruction and widening of 4-lane Highway 299, and re-vegetation of disturbed areas.


A review of all relevant water quality information – including permits, plans and designs, and maps – related to the project was performed and an initial site visit was conducted to gather information needed to develop the SWPPP.

Field Inspections and Monitoring

Site visits to the construction site were conducted on a weekly basis to inspect stormwater BMPs including sediment and erosion controls and non-stormwater discharge threats to water quality. Weather systems were tracked and, for qualifying rain events, a rain-event-action-plan (REAPs) was issued a pre-storm inspection was performed and reported. During-storm inspections included sampling and analysis for pH and turbidity; post storm inspections were done to evaluate BMP effectiveness.


Numerous reports were submitted on a regular or periodic basis, including - among others - weekly and quarterly Caltrans stormwater inspection reports, corrective action summary reports, sampling and analysis reports, NAL exceedance reports, weather logs, training logs, 401 Rainy Day reports, 401 Monthly Compliance reports and, finally, annual SWPPP reports.

Scope of Services: 


  • Preparation of a site-specific Storm Water Pollution Prevention Plan (SWPPP)
  • Stormwater best-management-practices (BMP) inspections, including weekly, pre-storm, during-storm, post-storm and quarterly inspections
  • SWPPP and 401 Permit stormwater sampling and analysis at 10 discharge and run-on locations
  • Communications with the project manager and site supervisor regarding stormwater issues
  • Stormwater BMP and SWPPP training for site workers
  • Weekly reporting using Caltrans stormwater report forms
  • Rain event and monthly compliance reporting for the 401 Permit
  • Preparation of annual reports.