Care for Landscapes and Lungs: Addressing Equipment Emissions

Trimmer web
Small off-road engines in landscaping equipment produce significant air pollution. Photo by Alec MacDonald.

Aaahhh, the refreshing smell of newly-mown grass! Whether it’s from the neighboring park or their own front yards, Bay Area residents are again getting that chlorophyll-laden breeze announcing the season of mowing, planting, and weeding. Unfortunately, all too often the breeze is also loaded with gasoline fumes from lawn and garden equipment.

Along with golf carts and some commercial utility equipment, the California Air Resources Board classifies gas-powered lawnmowers, trimmers, and leaf blowers within the category of “small off-road engines.” Small but dirty, these engines not only produce reactive organic gases and nitrogen oxides (both of which contribute to smog), but also emit particulate matter, which is a major health hazard. Michael Benjamin, chief of the Air Resources Board’s Monitoring and Laboratory Division, has said that by about 2020, small off-road engines will be generating more ozone-contributing pollutants than passenger cars.

According to National Geographic, one hour of gas-powered lawn mowing can produce as much pollution as four hours of driving a car.

The Air Resources Board plans to replace federal regulations on this equipment with more stringent state regulations. The effect of these new requirements will be gradual; the regulations will not take full effect until 2020, and even as cleaner models come on the market, it could be politically challenging to mandate that every owner or user must upgrade. It’s also a fact that cleaner gasoline-powered equipment still produces pollution, just not as much; a more effective way to cut emissions is to move to electric power.

Some agencies have already been tackling the problem by funding rebate or replacement programs to swap out gasoline-powered equipment. Beginning in 1999, the Bay Area Air Quality Management District offered cash incentives to residents to purchase electric or manual replacements for gasoline-powered lawnmowers. Approximately 8,000 lawnmowers with two- and four-stroke engines were replaced under these programs, creating an estimated reduction of 5.3 tons of pollutants in the region. However, according to the Air District’s draft Clean Air Plan, approximately 310,000 of the lawnmowers and leaf blowers in the Bay Area are still powered by the more highly-polluting two-stroke gas engines.

Since late 2014, the Air District has also been administering a program to replace commercial lawn and garden equipment in Alameda and Contra Costa counties, using $935,770 from pollution settlements. Priority has been given to school districts, with some funding going to other local jurisdictions. Joe Steinberger, an environmental planner for the agency, explained, “Our reasoning was that this equipment is heavy-duty and it’s operated much more frequently than residential equipment, so replacing it will have more impact on air quality. And school districts are ‘sensitive receptors’ because of the children, and they need the most protection from air pollution.” The funds have been used to replace internal combustion equipment — ranging from sit-down mowers to leaf blowers — with the equivalent in zero-emission and low-emission equipment. Batteries and chargers are included with new electric equipment.

Some early rebate and swap programs were hampered by the limited power or running time of the electric-powered replacements. Steinberger cited an Air Resources Board pilot program in the San Joaquin Valley and South Coast air districts, noting that “battery technology improved significantly between the Air Resources Board pilot and our program.” He reported that a survey showed Air District program participants were quite satisfied with the new equipment, with any limitations being offset by lower maintenance and less noise pollution.

Contra Costa County Ombudsman Michael Kent, who coordinates the replacement program for the Contra Costa County Public Health Department, also commented, “In survey feedback, we’ve heard that a big plus is the lack of vibration — workers using the gas-powered leaf blowers really get shaken up by that equipment.”

Despite its success, Steinberger cautioned that once the settlement funds are expended, there is no dedicated source of funding to continue the Air District’s program. This budgetary obstacle is also noted in the draft Clean Air Plan, which reports on the potential positive impact of these programs, and suggests expanding them to cover other equipment such as shredders and stump grinders.

According to the agency’s Air Quality Planning Manager Dave Vintze, “Small-engine lawn equipment has a lot of potential for emissions reductions, and it’s also important because this equipment is a local source of emissions right at ground level, at breathing level.” He confirmed that to be most effective, the agency would need to identify a multi-year funding stream. “It would be a concerted, long-term effort taking five to ten years to replace all the equipment,” he said, “but we believe it would prove to be cost-effective.”

Based on results of the commercial lawn and garden equipment exchange program, Steinberger predicted “there will be a continued move in this direction.” But how readily — and quickly — will residents and businesses make the switch? And how important is it to have a little help in the form of rebates or other programs?

Lacking a source of agency funding, reducing regional pollution from gas-powered lawn and garden equipment may come down to local businesses and residents making changes literally in their own backyards. They have some good reasons to do this, including health, noise pollution, and concern for the overall environment — and for those who love to be first with the newest gadget, there are some shiny new toys available, including a robotic mower that runs on lithium-ion batteries.

Robotic mowers are futuristic, cleaner, and expensive. Photo courtesy Consumer Reports.

Robotic mowers aren’t in the budget for the small landscape maintenance firms that do a sizeable part of the mowing, trimming, and leaf-blowing across the region. These are the businesses where lower-emissions equipment could make a significant impact. Without rebates or similar programs, the replacement rate may lag, but owners and operators are beginning to weigh the advantages of switching. In addition to reducing vibration, noise level, and exposure to gasoline fumes — major considerations for workers using the equipment many hours a day — electric equipment may save on operating costs as gas prices rise.

Reducing the use of gasoline in small engines like these isn’t just about decreasing fumes and noise, it’s also about protecting the environment by moving away from fossil fuels. This is a goal for Clean Air Lawn Care, a nationwide company that uses solar and wind power to recharge most of its equipment, while relying on biodiesel as a replacement for standard diesel in large engines. Mill Nash, who has run a Clean Air Lawn Care franchise in Mill Valley for about 10 years, said going electric means that he doesn’t come home smelling of gasoline, and needn’t worry about wasting fuel. “There’s a lot of spillage as people fill up these engines,” he noted about gas-powered equipment.

Sonoma County is home to another Clean Air Lawn Care franchise, and Nash believes that there are opportunities in the Bay Area for more to launch. Despite that sort of optimism, though, residents will have to wait and see if the region moves to the cutting edge of this issue.

Leslie Stewart covers air quality and energy for the Monitor.