Pennsylvania bears a huge responsibility for the despoiling of the bay. The Susquehanna, which drains half the state, pumps in 40 percent of the bay's nitrogen, largely from agriculture, and a gusher of its two other major pollutants - natural sediment and phosphorus from fertilizers and detergents - abetting the decline of the Chesapeake's celebrated fishing industry.
"As goes Pennsylvania," says J. Charles Fox, the Environmental Protection Agency's senior Chesapeake adviser, "so goes the bay."
Lititz Run, all 6.5 miles of it, is a microcosm of the problem. Though much has been done, the pollution runs deep and will be hard to totally reverse. Even as it first burbles forth in the quaint town of Lititz, about 75 miles west of Philadelphia, the stream is laced with harmful nitrogen, likely from decades of fertilizing nearby.
The stream's renewal represents a hopeful but cautionary tale for how difficult a real cleanup will be.
Experts say the efforts in Lititz need to be enhanced and then duplicated across 100,000 streams in the bay's watershed.
It won't be enough, they say, just to curb runoff, alter farm practices, and upgrade sewer plants.
Saving the bay will require a broader range of fixes across a wider swath of the watershed, the tenacity of governments, an influx of money, smarter development, and the long-term cooperation of virtually everyone living here, at a time when the population is increasing dramatically.
"We are 17 million people living in this watershed," says Don McNutt, administrator of the Lancaster County Conservation District, "and we're going to impact it. The farmers are feeding the people, and the people are flushing their toilets. That's the long and short of it."
