California Cleanup

Sept. 1, 2010

Water is precious in California, which makes protecting water quality critical. That’s why, as of July 1, 2010, a new California construction permit requires that all construction sites implement measures to prevent stormwater pollution from residential and commercial construction and development activities.

More than 100 streams in California’s coastal watersheds have been designated as having impaired water quality, which limits their beneficial uses. These watersheds have been added to the USEPA 303(d) listings and the National Pollutant Discharge Elimination System (NPDES) created to protect these watersheds. NPDES permits are issued to municipalities as well as construction sites, to ensure that national water-quality standards are met.

California Compliance
The California State Water Resources Control Board Web site states: “The State of California State Water Resources Control Board Construction General Permit requires the development and implementation of a Storm Water Pollution Prevention Plan (SWPPP). This plan should contain a site map(s) which shows the construction site perimeter, existing and proposed buildings, lots, roadways, storm water collection and discharge points, general topography both before and after construction, and drainage patterns across the project. The SWPPP must list Best Management Practices (BMPs) the discharger will use to protect storm water runoff and the placement of those BMPs. Additionally, the SWPPP must contain a visual monitoring program; a chemical monitoring program for “non-visible” pollutants to be implemented if there is a failure of BMPs, and a sediment monitoring plan if the site discharges directly to a water body listed on the 303(d) list for sediment.”

The SWPPP is designed to ensure compliance during the construction and post-construction phases of the project. Some example BMPs include slope stabilization and sediment control measures, containment of stockpiled materials, and an inventory of materials on the construction site. The SWPPP document must also identify all potential sources of pollution that may reasonably be expected to affect the quality of stormwater discharges from the construction site.

Prior to July 1, 2010, developers whose projects disturbed one or more acres of soil, or were part of a larger common plan of development that in total disturbed one or more acres, were required to obtain coverage under the General Permit for Discharges of Storm Water Associated with Construction Activity (99-08 Permit). Effective July 1, 2010, these same developers are required to obtain coverage under the new Construction Permit (2009-0009 Permit) adopted on September 2, 2009. Some of the changes found in the new permit include:

  • Establishing a “legally responsible person”
  • Training and designations for SWPPP developers
  • Training and designations for SWPPP practitioners
  • Recertification of the SWPPP through the Web-based SMARTs system
  • Determining the site risk level
  • Adhering to numeric action levels (NALs)
  • Maintaining numeric effluent limitations (NELs)
  • Generating a rain event action plan (REAP)
  • Implementing more specific construction BMPs
  • Monitoring for pH and turbidity
  • Receiving water bioassessments
  • Annual reporting

The new California permit’s goal is to minimize construction site discharge by including mandatory monitoring, REAP, and bioassessments.

An active construction site with numerous potential discharge points will need enough onsite staff to monitor the site during the storm. Each of the sampling staff is required to be a delegate of a Qualified SWPPP Practitioner. A minimum of three readings for pH and turbidity are required, taken from water samples collected at discharge points. These values are reported and compared to the NELs and NALs. Developers may also be required to submit the collection of discharge water to an analytical laboratory.

These mandatory monitoring requirements define the during-storm staffing requirements. Receiving water monitoring should be done when the turbidity of stormwater discharges from a construction site exceeds an NEL. This means collecting additional water samples from several places within the water body during the storm.

The REAP is a pre-storm requirement of the new permit. Construction sites are dynamic, and things can change quickly as stockpiles are moved and new areas are excavated. The REAP defines the stormwater sampling activities and suggested actions for each construction phase, and should be provided 48 hours before a 50% or greater chance of rain. The REAP should provide the construction staff with the most up-to-date information for the site so appropriate actions can be taken to clean up debris, cover stockpiles, and further define the site BMPs.

The new permit also defines the necessary stream bioassessments. A bioassessment evaluates the health of a body of water if the construction activities disturb more than 30 acres and discharge water directly into a sediment-impaired body of water. This assessment includes documenting the presence of crustaceans, crayfish, clams, snails, aquatic worms, and aquatic insects. It should also include the presence, condition, types, and numbers of fish, insects, algae, plants, and other organisms. The data provide direct, accurate information about the health of the specific body of water.

Meeting the Deadline
Landowners and contractors were required to recertify their SWPPPs by July 1. Missing the deadline means an existing construction permit will be terminated. If construction activities are still underway, a new 2009-0009 permit will be necessary. A Notice of Intent must be filed with a new or enhanced SWPPP. This means the SWPPP should conform to the new regulations and include the new items listed above, such as the risk level calculation, mandatory pH and turbidity monitoring, and more specific construction BMPs. What is uncertain is the regional board’s timing for taking action against violators and how many notices the board will send to current permit holders.

About the Author

Sean Porter

Sean Porter is a senior technical advisor and stormwater manager with SCS Engineers.

Photo 39297166 © Mike2focus |
Photo 140820417 © Susanne Fritzsche |
Microplastics that were fragmented from larger plastics are called secondary microplastics; they are known as primary microplastics if they originate from small size produced industrial beads, care products or textile fibers.
Photo 43114609 © Joshua Gagnon |
Dreamstime Xxl 43114609