DSRSD Working Toward a Greener Fleet

A hydrovac truck at a sanitary sewer overflow in 2020 in Dublin.

The Dublin San Ramon Services District owns, maintains, and operates a total fleet of 165 vehicles and pieces of equipment: 59 on road vehicles (registered and licensed); 23 electric carts; 1 electric forklift; 31 pieces of trailered specialty equipment (emergency generators, portable pumps and compressors); and 51 pieces of specialty equipment (a dredge, a crane, and permanent generators to name a few). Anything with an engine or motor, stationary or mobile, is considered part of the fleet. Vehicles range in size and complexity from the 66,000-pound (when filled) Vac-Con truck that vacuums and or jets clogs out of pipes to a 3,300-pound hybrid sedan.

The Fleet Management Program has three objectives: 1) to operate uninterrupted in normal and emergency situations; 2) to comply with all regulations; and 3) to purchase and maintain a cost-effective fleet.                

Provide Uninterrupted Service

To ensure uninterrupted service, Fleet plans their budget 10 years out and evaluates the replacement of vehicles using nine criteria: 1) safe to operate; 2) mechanical life span (the age at which large mechanical components—engines, transmissions, suspensions–start to fail, which is usually at the 10-year or 100,000-mile range for a standard duty vehicle and 15 years or 150,000 miles for a heavy duty vehicle); 3) cost to operate; 4) business need; 5) availability of parts; 6) environmental impacts and compliance with ever-changing regulations; 7) energy efficiency; 8) fuel source (diesel, biodiesel, gas, hybrid, natural gas, electric); and 9) mileage and age of vehicle. 

Comply With All Regulations   

In the fall of 2020, California Governor Gavin Newsom issued Executive Order N-79-20 requiring the following:

• By 2035, 100 percent of instate sales of new passenger cars and trucks will be zero-emission vehicles (ZEVs);
• By 2035, 100 percent off-road ZEVs and equipment, where feasible; and,
• By 2045, 100 percent of medium- and heavy-duty vehicles in the state will be ZEVs for all operations where feasible, including full transition to ZEV buses and long-haul trucks.

For ten years, DSRSD has been working toward a greener fleet by replacing its vehicles with smaller vehicles and replacing small pickup trucks with solar-charged, battery-powered electric carts. 

Today, the District has 23 electric carts. Most are equipped with toolboxes for plant mechanics and electricians. One cart is equipped with portable welding equipment. These carts are a more energy-efficient and cost-efficient way for plant operators, mechanics, and electricians to move about the 22-acre Regional Wastewater Treatment Facility (RWTF) and 50-acre land disposal site located across the street from the RWTF.

This is a good beginning, but the fleet is much bigger than 23 electric carts that move about the facility. Of the 59 vehicles traveling on the roads, 46 are gas-powered, 10 diesel, and 3 hybrid. Of the 83 pieces of specialized equipment, 26 are gas-powered, 25 diesel, 4 propane, one solar, one electric battery, 10 are stationary pieces of equipment that use plant electricity, and 16 do not require any power (trailers, etc.).

Electric carts are charged at the wastewater treatment plant.

Challenges to Achieving a Green Fleet

While the District intends to work toward a greener fleet, many factors are involved. Greener vehicles are not currently available to do the tasks required of some of the District’s specialty vehicles and equipment. Greener vehicles may exist but are not yet available on the market. Greener vehicles need to be clean-air certified. And finally, greener vehicles need to be not only energy efficient, but also cost efficient.

“Often the technology is not available to satisfy the District’s business needs with zero-emission vehicles,” says Mechanical Superintendent Shawn Quinlan. “But we do what we can: we reduce the total number of vehicles, replace heavier vehicles with lighter ones, and replace vehicles with more fuel-efficient, lower emission ones.”.

As technology advances, the District will transition its fleet to be greener, to be electric. However, are electric vehicles really greener?

Currently, regulators only monitor what comes out of the exhaust pipe of a vehicle and the amount of fuel it consumes. Should regulators be considering the carbon footprint left behind by creating the zero-emission vehicle (ZEV)? Should they be considering what happens to old electric car batteries at the end of their life of 10 to 15 years?

Batteries from electric vehicles are larger and heavier than batteries from gas-powered cars and are made up of several hundred individual lithium-ion cells, all of which need to be dismantled. These batteries contain hazardous materials–cobalt, nickel, lithium, manganese—and explode if disassembled incorrectly. Also, the process to recover cobalt, nickel, lithium, and manganese in a usable form is energy intensive. The motivation to recycled old batteries is that it is the safest way to ensure a ready supply of new batteries.

Current Fleet Activities

In 2021, DSRSD will auction off 19 vehicles, but replace only 11 of them. 

During the pandemic, the Centers for Disease Control mandated that field workers travel one to a vehicle, instead of the usual two. All administrative vehicles were devoted to field operators so they could work safely. Administrative staff were primarily working at home and attending meetings virtually. Consequently, the District kept vehicles they would have auctioned off. 

One criteria staff consider when replacing vehicles is the business need of the vehicle. Eighty percent of the on-road vehicles are emergency response vehicles. This means the District must have enough heavy duty Class C trucks to haul emergency generators wherever they may be needed to maintain our services and to tow or haul emergency pumps to dewater sites or transfer water. It means DSRSD has vehicles that can vacuum or jet clogs out of pipelines and vehicles that can respond to sanitary sewer overflows, water main leaks, sewer system leaks, and fire hydrant accidents. It means the District has trucks that enable workers to maintain and repair pump stations and a large variety of field equipment, and to carry small equipment and materials to conduct repairs and maintenance anywhere in our service area.

To truly achieve a greener fleet, new vehicles will need to be developed. For example, electric vehicles are usually lightweight, and some of the trucks are necessary to maintain water, wastewater, and recycled water systems—like the VacCon trucks that vacuum and jet pipes to remove clogs—do not come in the form of electric vehicles, yet.

Ford recently revealed the F-150 all-electric truck that has a 250-mile range, a generator that offers 9.6 kW of maximum power through 11 outlets (back-up power that can provide full-home power for up to three days on a fully charged battery or as long as ten days if rationing power), and over-the-air software updates. However, the price tag ranges from $40,000 (basic truck, no frills) to $90,000 (fully loaded). Typically, the District spends $29,000 to $31,000 on a similar gas-powered truck.

Regulations

The California Air Resources Board (CARB) regulates mobile sources of air emissions from on-road vehicles because they move throughout the state. Vehicles and mobile equipment are subject to numerous regulations, depending on the type of equipment and the fuel used. The District’s gas-powered vehicles are constantly monitored (via software built into the vehicle) for smog emissions. And District diesel-powered vehicles undergo SNAP tests (Sudden Neutral Application of Power) conducted by staff to determine how clean they are running.

Vehicles powered by fossil fuels are the largest source of greenhouse gas emissions in the state. That is why CARB is developing an integrated approach to transition California to cleaner technologies to achieve California’s air quality and climate protection goals.  CARB goals are as following: 

• By 2030, achieve greenhouse gas emissions 40 percent below 1990 levels; 
• By 2045, achieve carbon neutrality (zero carbon footprint); and, 
• By 2050, achieve greenhouse gas emissions 80 percent below 1990 levels.

Regulations impact many aspects of a fleet. For example, regulations place limits on emissions which may force the District to replace older equipment. Currently, the District has a crane with a 28-ton lifting capacity used to maintain and remove pumps and rooftop equipment. This crane must operate at Tier 4 (essentially it must pass the smog test) or it has to be retired and replaced.

Regulations impact purchasing requirements, as detailed in the Governor’s Executive Order N-79-20. 

Regulations impact operations. For example, the District is limited in the number of hours it can operate portable generators. However, during Public Safety Power Shutoffs, such limitations are waived.

And finally, as with all government regulations, there are reporting requirements (e.g., which are mostly online these days and easier to complete).

In addition to CARB regulating the District’s on-road vehicles, the Bay Area Air Quality Management District (BAAQMD) regulates stationary sources of air emissions like the District’s emergency diesel standby generators and cogeneration engines. These are essentially locomotive engines that mix digester biogas, methane, with natural gas to produce electricity and power the treatment plant.

Posted: July 8, 2021