More than 2,000 aging Colorado school buses have been retrofitted over the past eight years to limit diesel exhaust emissions, which are known to worsen asthma and other lung ailments, especially in children.
But recently announced federal budget cutbacks have slashed spending for the Environmental Protection Program’s Clean Diesel Program, which pays for the retrofits.
And for every Colorado school bus that has been retrofitted so far, officials estimate there’s at least one more that hasn’t been but ought to be.
Should the federal funding not be restored, officials aren’t sure what will become of state plans to retrofit the remaining buses. It’s possible that other funding sources could be found but there are no guarantees.
“We’ll be retrofitting buses at least through Sept. 30 and probably beyond,” said Lisa Silva, air quality planner for the Air Pollution Control Division of the Colorado Department of Public Health and Environment and manager of the Clean Diesel Program for the state.
“We’ve applied for another grant, which could go through 2012. We just have to wait and see what happens after this fiscal year.”
‘Clean Diesel’ retrofitted 2,000 buses
The state-run Clean Diesel Program, launched in 2006, targets school districts outside the metro area. It has retrofitted about 1,000 buses in Pueblo, El Paso, Garfield, Rio Blanco and Weld counties, at a cost of about $3.4 million.
A threat to children
“Students could be breathing this in twice a day, five days a week, nine months a year for 12 years.”
— Greg Davis, EPA
In Denver and its suburbs, a similar program is administered through the Regional Air Quality Council. Launched in 2003, RAQC has retrofitted about 1,000 buses in the seven-county metro area, at a cost of about $3.5 million.
Later this year, buses in Gunnison, Cotopaxi, Dolores Re-2 and Bayfield school districts are due for retrofits but at least a dozen other school districts have requested assistance. Silva estimates there may be 3,000 buses still running on Colorado roads that are needlessly belching toxins into the air – and likely into the lungs of their passengers.
“Researchers at National Jewish tell us they see a lot more asthma attacks that are very likely induced by school bus rides on diesel school buses that are not retrofitted,” Silva said. “That’s an immediate effect. Long-term, there have been studies that show exposure to mobile source air toxins can do permanent damage to the lungs by the time a child is 18.”
Rural riders particularly at risk
The problem is particularly acute in the state’s rural areas, where students may spend upwards of two to three hours a day on board buses. That doesn’t count time spent traveling to and from sporting events, which can add additional hours of bus travel.
Buses by the numbers
- Nationwide, an estimated 24 million children ride school buses every day.
- Almost 400,000 diesel school buses are in use – their average age is 10 years old.
- More than 75,000 buses have been on the road since before 1990.
- 20-year-old buses are estimated to emit six times the number of toxic particles as buses built before 2004 – and as much as 60 times more than buses built since 2007.
- But at a cost of $125,000 to $175,000 per bus, school districts are slow to replace old buses with new ones.
The emissions seep in through the doors opening and closing at stops, but also come in from under the hood. The exposure to these toxins is greatest inside the school buses, but non-riders can be exposed while waiting with children at bus stops or stopping behind an idling bus.
Children are at greater risk than adults because their lungs are smaller and because their respiration rate is faster. While adults average 12 to18 breaths per minute, young children may inhale 20 to 40 times per minute. And with each breath they could be inhaling carbon, formaldehyde, and other toxic chemicals found in diesel exhaust fumes.
“Students could be breathing this in twice a day, five days a week, nine months a year for 12 years,” said Greg Davis, Mobile Sources Program Manager for the EPA in Denver, which oversees the Clean Diesel grants. “With each $1 you put into reducing pollutants, you get more than $1 back in reduced health care costs.”
Buses built before 2007 – the year emission control devices became standard on new buses – are eligible for the retrofits, which involve up to three pieces of equipment:
- Diesel oxidation catalysts, which replace the existing bus mufflers and which decrease tailpipe emissions by 50 percent for hydrocarbons and 20 percent of particulate matter.
- Crankcase filtration units, which collect burnt oil particles and other emissions that sweep in from under the hood, and reduce them by 95 percent.
- Engine pre-heaters, small motors that reduce idling by reducing the time buses need to warm up in the morning. Pre-heaters can save 1 gallon per bus per day of diesel fuel.
The cost to retrofit a bus with all three pieces of equipment averages about $3,500, though not all buses have received all three.
Metro districts further along than rest of state
In the Denver metro area, nearly all eligible buses have been retrofitted to reduce tailpipe emissions and many have been fitted with the engine pre-heaters. But fewer have received the crankcase filtration units.
“Done is relative,” said Steve McCannon, mobile sources program manager for RAQC. “The work will never be done. But we’ve definitely made more progress in the metro area than in the rest of the state.”
He said a lot of metro area school districts have also moved to install GPS systems on their buses. His office has provided 350 of those.
“The benefits to GPS are great. The first piece is knowing where the buses are. We can tell what buses are out there and not moving. We can see if a bus driver is wasting money just sitting in a parking lot. We can also do route optimization,” McCannon said.
The CDPHE and RAQC programs have excelled at getting federal funds, particularly federal stimulus dollars, to pay for these programs. But in February, President Obama’s proposed budget eliminated funding for the Clean Diesel Program, which has proven hugely popular and has bipartisan support.
Nationwide, an estimated 24 million children ride school buses every day and almost 400,000 diesel school buses are in use. Their average age is 10 years old, and more than 75,000 have been on the road since before 1990. Twenty-year-old buses are estimated to emit six times the number of toxic particles that buses built since 2004 emit, and as much as 60 times more than buses built since 2007. But at a cost of $125,000 to $175,000 per bus, on average, cash-strapped school districts are slow to replace old buses with new ones.
That’s why the retrofitting program has been so popular: Relatively speaking, it’s an expensive way to dramatically curb emissions without buying a whole new bus.
“This seems like kind of a no-brainer,” said Lauri Smock, transportation coordinator for the Gunnison Watershed School District, which has been waiting for two years for the state to retrofit its 19 buses.
“We’ve been trying, unless it’s stupid cold, to turn our buses off when they get to the schools and not keep them idling, because schools say they know when buses pull up because they can smell the fumes. The other thing is, in the winter we have our buses plugged in all the time,” she said.
“Those are big engines that have to stay warm. We’re using a lot of money on electricity keeping the buses warm so they’ll start when it’s 20 below outside. But with the pre-heater, it’s timed, it will come on a couple of hours before the driver gets there in the morning and the driver won’t have to plug the bus in, so it will cost us less. It will be just a wonderful program for us.”
GPS tracking touted for bus use
In the Adams County Five Star School District, all 160 buses are now equipped with the latest emissions equipment.
Transportation director David Anderson said that district is exploring all the ways in which even fancier bells and whistles – like GPS – can be used to curb pollution and boost fuel efficiency.
“GPS has been an amazing tool,” Anderson said. “We know where every bus is at a given moment. I can tell you how long the engine has been running, how long it’s been idling. I never thought it would be as wonderful as it is. At my fingertips, I get instant reports if a vehicle has been idling more than 10 minutes. Think how much fuel that can save.”
Cost to install GPS is $600 per bus. Anderson said he recouped the cost within the first year.
Last year, the district also installed card readers on all its buses, which automatically track when individual students get on and get off. That information helps district officials keep track of ridership, and lets them reconfigure bus routes to avoid empty seats and increase fuel economy.
It also is a student safety tool.
“I don’t think a day goes by when we don’t have a lost elementary kid,” Anderson said. “They get on the wrong bus or get off at the wrong stop. The little ones get easily disoriented. Now, if a first-grader gets lost, I can tell he got off at 1st and Main at 3:20. In the past, it was just a guess. Now I have true documentation that’s instantaneous.”