Due to its favorable climate and proximity to large southern California markets, the Carpinteria Valley has become home to a substantial greenhouse industry, with more than 175 greenhouses run by 51 greenhouse and nursery operators.

Unfortunately, for many years these greenhouses were unlawfully discharging wastewater laden with fertilizers into Santa Monica and Franklin Creeks, which flow directly into the Carpinteria Salt Marsh. Monitoring by UCSB and other entities over the years has revealed elevated levels of nutrients (nitrate and phosphate) in Franklin and Santa Monica Creeks, and research has shown that the greenhouse industry was a major contributor of these nutrients.

An overabundance of nutrients in water causes eutrophication by stimulating the growth of algae and other organisms that deplete oxygen in the water. Excessive nutrients can also trigger harmful algae bloom outbreaks known as Pfiesteria (also known as red tide), which discolors water and produces toxins that are harmful to marine organisms and humans.

In an effort to ameliorate this problem, the Regional Water Board sent a letter to each Carpinteria greenhouse operator in July 2001 requiring them to describe the measures they would take to eliminate their discharges. While some responded that they had recently or were soon planning to convert to hydroponic systems (which generate much less wastewater and require less fertilizer than other growing methods) and recycle their irrigation runoff, others failed to respond sufficiently or accurately, hinting at an ongoing problem.

Channelkeeper had been monitoring discharges from the greenhouses for some time, walking Santa Monica and Franklin Creeks and photographing and taking samples of illegal discharges from several greenhouses. In December 2002, Channelkeeper staff presented this evidence to the Regional Water Board, who then directed its staff to inspect the greenhouses. In January 2003, Channelkeeper led Regional Water Board enforcement staff on a guided tour of the Carpinteria Valley, highlighting illegal discharge points from the greenhouses. We continued to lobby the Water Board to maintain pressure on the greenhouse operators to clean up their operations.

As a result of our combined efforts, greenhouse operators installed new water reclamation technology and are now saving money on water, fertilizers and pesticides. Today, discharges from the greenhouses have largely stopped, the creeks are no longer clogged with algae, and the Carpinteria Salt Marsh is healthier.

We consider this a success story and a model of Channelkeeper's effectiveness in bringing regulators and dischargers to the table to stop the unnecessary pollution of our precious coastal resources. Channelkeeper will continue to monitor the Carpinteria greenhouses and Franklin and Santa Monica Creeks periodically to ensure ongoing compliance.