State to regulate Caltrans runoff

The State Water Resources Control Board will hold a meeting at 9 a.m. Sept. 19 to consider adopting a draft National Pollution Discharge Elimination System (NPDES) Statewide Storm Water Permit for Caltrans.

Walt Shannon, chief of the Municipal Storm Water Unit, said the new permit regulations govern Caltrans’ discharges of storm water and non-storm water from roads maintained by Caltrans along with any highway trash and pesticides used by Caltrans that find their way into the state’s waterways.

Shannon said there are a number of changes to the proposed new permit. The first is special protection for discharges of storm water to areas of special biological significance. Shannon said these are all coastal areas and the protections are designed to maintain the natural water quality.

A second change concerns TMDLs which is a calculation of the maximum amount of pollutant that a water body can receive and still safely meet water quality standards. TMDL stands for Total Maximum Daily Load Implementation. The draft proposal would require Caltrans to bring its permit into conformance with the waste load allocations and implementation requirements of the Clean Water Act. Shannon said these limits are water body specific and only certain pollutants and water bodies require pollution controls to meet their waste control allocation.

A new water quality monitoring and reporting program is also part of the draft permit as is a program effectiveness review. In addition, Caltrans would be required to meet the same requirements as any other construction site in the state.

Last, the new permit adds requirements and new design standards for post-construction treatment controls, sustainability, hydromodification, and “Low Impact Development.” According to the State Water Resources Control Board, these green infrastructure requirements are designed to maximize the beneficial uses of storm water through recovery and recharging of regional groundwater.

Caltrans’ current Storm Water Management Plan (SWMP) describes the procedures and practices used to reduce or eliminate the discharge of pollutants to storm drainage systems and receiving waters. The SWMP will be considered for approval by the State Water Board along with the new permit provisions.

Before July 1999, stormwater discharges from Caltrans’ stormwater systems were regulated by individual NPDES permits issued by the Regional Water Boards. On July 15, 1999, the State Water Board issued a statewide permit which regulated all stormwater discharges from department-owned maintenance facilities and construction activities. The existing permit will be replaced upon adoption of a new permit.

Shannon said the State Water Resources Control Board has held multiple hearings on the proposed changes to the permit. “Hopefully this will be the final,” he said.

The adoption meeting be held at the Joe Serna Jr. Cal EPA Headquarters Building, Coastal Hearing Room, at 1001 I Street, Second Floor, Sacramento.

Online, people can read about the program and comments from previous hearings at waterboards.ca.gov/water_issues/programs/stormwater/cmnt062612.shtml.

They can also contact Walt Shannon with their questions at 916-341-5497.

Contact Dawn Hodson at 530-344-5071 or dhodson@mtdemocrat.net. Follow @DHodsonMtDemo on Twitter.