Few saw it coming, but the General Assembly approved a sleeper environmental bill that will require thousands of homes in Maryland to install more costly nitrogen-removing septic systems to keep the polluting nutrient out of rivers and the Chesapeake Bay.
Bay advocates are hailing the septic legislation's passage as a significant boost for the beleaguered Chesapeake, coming as it did near the end of a legislative session dominated by budget woes.
"It's really, really amazing," said Sen. Michael G. Lenett, a Montgomery County Democrat and the lead sponsor. "For too long we have known exactly what we needed to do to clean up the bay, and yet we have been unwilling to do what's necessary."
Lenett confessed he was surprised by the bill's success in the last days of the legislative session that ended Monday. He figured it was a "long shot" that would require at least a couple of years of debate and tinkering before enough lawmakers would go along with it.
The last time anyone made a serious run at this was a decade ago. Gov. Parris N. Glendening's proposal died in committee amid an outpouring of protest from builders and real estate agents.
The opposition was fierce again this year, as critics complained that the added cost of the enhanced septic systems would hurt an already crippled housing industry and unfairly burden rural homeowners.
The measure was scaled down to require the nitrogen-removing technology only for new systems in the "Critical Area," land near the Chesapeake, its tributaries and coastal bays. It passed the Senate by a single vote, 24-23, then cleared the House over the weekend after a lengthy, emotional debate.
Supporters argued it was high time Maryland did something to curb nutrient pollution from septic systems, a primitive waste treatment technology that allows homes to be built beyond the reach of sewer lines. There are 420,000 septics statewide, with thousands more added every year.
"Septics are really an uncapped, untouched source" of pollution, said Kim Coble, Maryland director of the Chesapeake Bay Foundation, which lobbied for the bill.
Baywide, septic systems produce only about 5 percent of the nitrogen fouling the water and causing fish-killing dead zones - far less than comes from farm fertilizer or sewage treatment plants. But in bay rivers where homes on septics crowd the waterfront, they can account for 25 percent to 30 percent of the nitrogen pollution, experts say.
Indeed, some of the rivers in the poorest health - the Patuxent, Severn, South and West - are those where many homes are on septic systems, said William C. Dennison of the University of Maryland Center for Environmental Science.
While a conventional septic system is designed to capture solids in a tank and neutralize disease-causing bacteria, the nitrogen seeps out unchecked through the drain field into groundwater and nearby streams.
In contrast, nitrogen-removing systems use motorized fans or pumps to inject air into the waste, stimulating bacteria that remove nitrogen from the wastewater, converting it to a gas, which is then expelled into the air. Such systems can reduce nitrogen levels in effluent by half or more, said Thomas H. Miller of the Maryland Cooperative Extension.
The state has been encouraging homeowners to voluntarily upgrade their septic systems, offering to cover the roughly $12,000 added cost of nitrogen-removing technology over a conventional system with funds raised from a $30 annual fee assessed on all current septic owners. To date, the Maryland Department of the Environment has underwritten 638 upgrades or replacements of old, failing septic systems.
At least three counties - Anne Arundel, Queen Anne's and Worcester - already require nitrogen-removing septic systems for new homes along the waterfront.
When signed into law by the governor, the state legislation will require the special systems for any new or replacement septic system within 1,000 feet of the Chesapeake and its tributaries, as well as along the coastal bays near Ocean City. Officials estimate there are 51,000 septics in those environmentally sensitive zones.
The measure requires the Department of the Environment to help homeowners pay for the added cost of a nitrogen-removing system, but only "if sufficient funds are available."
Realtors and homebuilders complained that the state should be required to pay for the systems if it was going to mandate them. Rural legislators also bridled at the requirement, which they said could hit the pocketbooks of struggling farmers and watermen.
"It's another increase in the cost of housing," said Michael Harrison of the Home Builders Association of Maryland.
But advocates said that while there is ample money to pay to replace existing septic systems near the waterfront, they did not believe the state should have to pay for pollution reductions that ought to be a condition of building a new home by the bay.