Maintenance facilities built with environment in mind
A little more than a century ago, America’s public transit was animal-powered. Maintaining those streetcar fleets included oiling wheels, keeping the cars brightly painted and providing plenty of hay, oats and water for the horsepower. The cars and horses were serviced and housed in barns.
As buses and streetcars changed and grew in size, maintenance facilities were remodeled and updated, but the old buildings simply had not been designed to accommodate modern vehicles and their servicing needs. Today, a new breed of transit maintenance facility – one that is sleek, efficient and environmentally friendly – has replaced those antiquated barns.
Federal regulations contributed significantly to the improvements, according to Don Leidy, managing principal of Denver-based Maintenance Design Group, a co-venture of Carter & Burgess, Fort Worth, Texas, and RNL Facilities Corp., Denver. “In the 1970s, when the federal government began providing funding for capital improvements such as maintenance facilities, part of the package was a requirement to design state-of-the art facilities,” he says. “The government felt that investing capital in the most modern technology would help transit operators reduce long-term operating costs.”
Major environmental laws enacted in the 1970s, followed by extensive EPA regulations in the 1980s, stressed pollution prevention and control in the design of vehicles and the facilities in which they are maintained. Additionally, vehicle technology shifted from mechanical and electrical to electronic, as microchips began to operate destination signs, fare boxes and engine controls. Repairing electronic technology demanded an entirely new level of sophistication and cleanliness.
Finally, the Clean Air Act Amendments (CAAAs) of 1990 required that urban transit buses achieve aggressive reductions in air emissions. As a result, most new facilities are designed to use or accommodate future use of electric-powered vehicles and vehicles that use alternative fuels such as compressed natural gas (CNG), liquefied natural gas (LNG), “clean” diesel and methanol.
Because CNG and LNG are invisible and difficult to detect, and because methanol is more flammable than other fuels, accommodating alternative-fuel buses can call for completely different fuel-handling technology, vapor venting, explosion-proof fixtures and special sensing devices to warn of leaks. If a number of vehicles will be using CNG, additional fueling lanes may be needed since CNG fueling takes twice as long as diesel fueling.
Most transit agencies constructing new facilities, including the Clark County (Nev.) Regional Transportation Commission, are providing for a future shift to alternative fuels, even if it is not clear which alternative is likely to be chosen. The county’s new $31 million facility has been designed to accommodate CNG-and future LNG-powered buses.
Besides its indirect effect in prompting a switch to alternative fuels, the CAAAs directly regulate protection of workers from toxic air emissions. That means indoor parking facilities must be designed with an adequate HVAC system.
Exhaust fans must be big enough to remove engine exhaust fumes. Additionally, flexible piping can be attached to bus tail pipes so that fumes from engine tests can be directly vented to the exhaust system. Enclosed paint booths, which prevent the spread of paint fumes, also are important.
In addition to meeting the requirements of the CAAAs, maintenance facility designers must consider the Clean Water Act as well as regulations pertaining to underground fuel storage tanks. For example, under the Clean Water Act, floors in areas where vehicles travel, are repaired or are fueled must have drains so that any spills are captured. Drainage must flow into an oil/water separator before being discharged into the sewer system, and the storage and distribution of oils, fluids and lubricants must be carefully monitored.
Facilities have typically stored diesel fuel and other fluids in underground storage tanks, but regulations governing underground tanks have become more stringent. Consequently, many new facilities are shifting to above-ground tanks, which are much easier to inspect.
Bus washing is another activity that demands controls because both the cleaning agents and grime on the bus are potential pollutants. At the Clark County facility, the bus wash is housed in a specially designed building, separate from the maintenance facility. Cleaning solvents are environmentally friendly. Washwater drains to a trench located in the center of the wash bay and on to a water reclamation system, which separates greases, oils and solvents before returning the water for reuse.
Beyond compliance with regulations and protection of the environment, a good facility design can result in cost savings and a more productive workforce. “A key benefit of any new or retrofitted facility should be to help reduce day-to-day operating costs,” says Leidy. “This can be accomplished by designing for the functional requirements of the facility, as well as by improving worker productivity through better lighting and improved repair bay design – what is called ‘human engineering.'”
Clearly, transit maintenance facilities have undergone major change in recent years as Americans strive harder to preserve clean air and clean water. Local governments may complain about the initial expense of state-of-the-art maintenance buildings, but ever-increasing environmental regulations and advancing technologies dictate nothing less.