An innovative system to manage dairy waste is about to be installed on Point Reyes' Kehoe Dairy on Pierce Point Road.

The new system - the first one installed on a dairy ranch anywhere - is a part of UC Berkeley project that is being coordinated by the Marin Resource Conservation District. The system would reclaim water, nutrients and energy from the waste of 500 Holsteins.

"The biggest environmental problem we have to watch is the dairy waste management," said Tom Kehoe, who manages the 1,200-acre ranch with brothers Tim and Mike.

The Kehoe brothers - Tom, Tim, and Mike - are open to "innovative strategies," UC Berkeley Professor F. Bailey Green, the project coordinator, told The Light. "I think they have a real love for the land."

Their brothers' grandfather bought the ranch in 1922, and their father Skip, who is now semi-retired, ran the ranch before them.

Since 1971, the Kehoe family has leased the ranch from the Point Reyes National Seashore. When the time comes, they intend to renew their 30-year lease, said Kehoe during a June 29 tour of the ranch sponsored by Marin Agricultural Land Trust.

Now the Kehoes spend $10,000 every year to clean their manure pit and spread it as fertilizer over their pastures.

The new system, called the Advanced Integrated Wastewater Pond System, was developed in the 1950s by UC Berkeley Professor William J. Oswald and is now used in non-farm development (for instance a similar system is proposed for the French Ranch development in the San Geronimo Valley).

It uses a chain of ponds, each with a unique function. First, the manure is pre-treated in one or two slurry tanks near the freestall barn, where cows are kept in bad weather or after milking.

Sand (used as bedding) and manure are flushed into the tank, where the sand settles to the bottom.

An agitator separates the solids from the liquids, with the effluent then getting pumped over a sloped screen.

Undigested greens (the food cows did not metabolize) would get caught in the screen. It could be used as bedding in the freestall - instead of sand - or as mulch, Green said.

The wastewater then goes to a pond that is deep enough to allow methane fermentation. The methane produced would be collected and used for energy on the ranch.

The effluent then goes to a second, channeled pond. There, a slow moving paddle wheel gently mixes the water, allowing algae to grow. The algae in turn produces oxygen and further disinfects the waste water.

The effluent, algae included, would then enter a third type of pond. Algae would settle there and be collected.

Using methane produced in the first pond, the algae could dried and used as a protein-rich feed supplement.

And the water would be pumped back to the flush tank of the freestall barn and used to clean the barn as many times as 10 times a day, Green said. Now the Kehoes flush the barn with fresh water twice a day.

UC Berkeley is helping to fund the project, although the main grant - $120,000 - comes from the state Regional Water Quality Board at the request of the Marin RCD.

"We've been successful at building our credibility [with the Regional Water Quality Board]" said RCD President Hank Corda.

Although the Point Reyes Station-based RCD has worked in coordination with other agencies before, this project will be the first involving the National Park Service, Corda noted.