Major manure cleanup in northwest Santa Rosa (w/video)
At a former dairy northwest of Santa Rosa, not far from the banks of Windsor Creek, the world’s largest pooper scoopers are hard at work.
In what has got to be one of the world’s dirtiest jobs, excavators and bulldozers are clearing two massive lagoons of untold tons of sloppy brown sludge.
One dozer, half-sunk in the muck last week, pushed load after load of the stinky ooze toward a spot where an excavator, perched precariously on the berm above, scooped it up with a huge shovel, swiveled 180 degrees and deposited it on a nearby field to dry.
For decades dairyman Marvin Nunes temporarily stored manure from up to 600 prized Holsteins in these two ponds at the northern end of his 177-acre Ocean View Dairy, nestled between the Charles M. Schulz Sonoma County Airport and the Russian River.
Now the messy cleanup operation is underway, funded not by the property owners, but by the ratepayers in Santa Rosa, Rohnert Park, Sebastopol and Cotati.
Santa Rosa’s Board of Public Utilities last month agreed to pay $330,000 to help the new owners, a vineyard development firm lead by a Kendall Jackson winery executive, remove the years of accumulated waste material from the ponds.
With such massive reservoirs of potential pollution so close to Windsor Creek, regulators have long been concerned that future floodwaters could inundate the property, spilling huge volumes of nitrogen and phosphorus into the Laguna de Santa Rosa, the most impaired water body on the North Coast.
In exchange for funding the cleanup, the city of Santa Rosa, which runs the Laguna Treatment Plant about 10 miles to the south, will receive mitigation credits for the project. The city will be able to use those credits to avoid stiff penalties from regulators if it pollutes the Laguna in the future.
“It’s a win-win. He gets the property cleaned up and we get the credits,” said David Guhin, the city’s director of utilities.
Once the manure from the dairy dries, it will be transported to a local composting operation.
The dairy cleanup is the latest and most expensive project to date in an innovative program taking a holistic approach toward removing sources of pollution from the Laguna de Santa Rosa watershed.
Much like carbon-credits aim to offset the environmental harm of one activity, such as air travel, by funding environmentally beneficial projects elsewhere, such as construction of wind farms, the city’s “nutrient offset program” allows it to compensate for the damage its pollution causes to the Laguna by cleaning up or preventing pollution into other parts of the watershed.
The effort has already paid for the improvement of roads at Pepperwood Preserve high in the Mayacamas in an effort to reduce sediment into Porter Creek. It has also funded changes to how manure is managed at Beretta dairy southwest of Santa Rosa to limit runoff into Roseland Creek.
But the cleanup of the former Ocean View Dairy is the city’s most ambitious one to date, promising to generate five times more credits than the previous two projects combined, according to Rita Miller, an engineer in the city’s utilities department.
Depending on how much material is actually removed from Ocean View’s ponds, the city stands to gain credit for between 22,500 and 27,500 pounds of phosphorus. For every pound of phosphorus removed, the city will receive one credit.
Those credits will give the city some important breathing room from regulators. The North Coast Water Quality Control Board has ordered the city not to add to the phosphorus levels in the Laguna.
While the city recycles about 98 percent of its treated wastewater, most of it through a 42-mile pipeline to The Geysers geothermal power plants, the Llano Road treatment plant still needs to discharge to the Laguna in a typical year.
Over the past several years, largely because of the dry weather and aggressive recycling programs, the city hasn’t needed to discharge anything into the Laguna.
But it historically has been forced to release treated wastewater during heavy rains. This adds nitrogen and phosphorus to the aquatic environment, triggering fast growth of aquatic plant life and reducing the oxygen levels in the water.
The low oxygen levels, excessive sediment and high summer water temperatures all combine to create an inhospitable environment for aquatic wildlife. Juvenile cold-water fish such as threatened steelhead trout and endangered coho salmon are particularly vulnerable to such conditions.
While regulators study how much phosphorus and nitrogen the Laguna can safety handle, they are requiring the city to adhere to a “zero net load” policy for phosphorus. That means if the treatment plant released 10,000 pounds of phosphorus in a year, it would have to prevent the same amount from entering other parts of the watershed.