It isn’t always easy being green.

Just ask the City of Manteca.

The city has the start of the solution for significant water conservation and – under the Global Warming Solutions Act mandate – reducing greenhouse gas in place but isn’t pulling the trigger.

Municipal leaders are gun shy about proceeding with the use of treated wastewater to irrigate the Big League Dreams sports complex and landscaping in and around Stadium Retail Center due to unclear and ambiguous state regulations.

“The rules the state has made aren’t very clear,” noted Manteca Public Works Director Mark Houghton. “We’re going to let someone else get out in the front of this one. We don’t want to be the guinea pig this time around.”

The guinea pig Houghton is referring to is the ill-fated and costly city attempt to meet a previous air quality objective imposed by state agencies by using methane gas to co-generate power to run the wastewater treatment plant.

The methane gas – which is still being burned off today into the valley’s polluted skies – is an unavoidable byproduct of the treatment process. The Environmental Protection Agency is so convinced that methane gas is detrimental to health that they have even targeted another big methane source - dairy cows.

Manteca in 2002 had a plan - and the tentative blessing of the state Air Resources Board - to eliminate methane gas pollution at the treatment plant.

In doing so, they could also reduce Manteca’s $1 million annual power bill to run the treatment plant by 40 percent.

Eleven years later, the $600,000 package plant sits unused while methane gas continues to add to the woes of the San Joaquin Valley - described by the federal government as one of the two dirtiest air basins in the nation.

That’ because between ordering the co-gen plant and taking delivery - the state changed the rules for such equipment. It determined the diesel-powered plant wasn’t clean enough even though the net reduction in air pollution from elimination of the methane gas would still be overwhelmingly significant.

That’s one example why local government officials throughout California are a little more than tepid about the mandates of Assembly Bill 32.

Manteca has had purple pipe - the color universally given to pipe containing recycled treated wastewater used for landscaping and even crop irrigation - in the ground since the dawn of the 21st century. They continue to put it in place as development occurs so the system will be there when it eventually is utilized.

But they are in no rush to move forward even though the city had gotten a tentative OK from the Central Valley Regional Water Quality Board to do so. That’s because, as Houghton notes, the rules for recycled wastewater’s uses are murky.

Meanwhile, Manteca has found a way to reduce the use of expensive treated water to irrigate many parks by tapping into non-potable water from high water tables. Such a well has already been put in place at the Big League Dreams sports complex for temporary use until the state can be clear on how Manteca can utilize its purple pipe water permit.

The solution reduces water use and saves money at the same time. Being able to use recycled wastewater to do the same park irrigation would increase those savings.

Air quality gurus have prompted Manteca to include a 20 percent reduction in water in the mandated global warning solutions plan now being formulated. It is a way to meet the city’s state mandated goal of cutting overall greenhouse gas production from private and public sources within the city limits by 12,014 metric tons by 2020. That goal also takes into account city growth.

The reduction in pollution is tied directly to city wells that pump water from underground aquifers as well as other power needed for the water treatment process at both the well heads and the water Manteca receives from the South County Surface Water Treatment Plant. That surface water plant already is powered mostly by a massive solar farm next door on Dodds Road near Woodward Reservoir.

Manteca as an entire community generated 408,869 metric tons of carbon dioxide equivalents in 2010. Based on growth projections and current usage, Manteca will generate 548,437 metric tons of emissions in 2020. State regulations being implemented on everything from how car engines are built to blanket air quality standards and water use regulations is expected to whittle that number down to 441,668 metric tons in 2020. Manteca’s community target as assigned by the state, though, is 429,693 metric tons of emissions.

That means Manteca has to come up with city driven ways to reduce projected emissions by another 12,014 metrics tons a year.