Harvard Raft Race, circa 1980

Once upon a time, when I had the misfortune of assisting with an entry in the annual Charles River Raft Race for Unusually Bored Harvard Undergrads, I was informed by one of my rather moist companions that Harvard University Health Services recommended tetanus shots for anyone who had come in contact with the Charles. No one was standing at the finish line to administer said shots, and our raft didn’t make it anywhere near the finish line anyway, so I simply went home, had a hot shower, and scrubbed very, very hard.

Now, it’s the week of the Head of the Charles, and no one is talking about injecting rowers with anything at all. The Charles River is safe for boating and safe for swimming below the Massachusetts Avenue bridge most of the year, according to the Charles River Conservancy. It hasn’t always been safe to swim. Heck, the lower Charles River wasn’t even a fresh-water river until 1910.

Therein lies the tale; human intervention nearly destroyed the Charles River, and human intervention has been restoring it to  health, or at least safe swimming.

Waltham's Watch Factory along the Charles River, photo by Josh Reynolds for the Boston Globe

The Charles River was once a free-flowing tidal estuary, with salt water tides bathing the Back Bay mud flats. Europeans changed all that. The Back Bay was filled with gravel and charming townhouses, and the Charles River Watershed Association reports that by the end of the 19th century, there were more than 43 mills along the Charles and 20 dams. The dams blocked the river’s flow, the mills dumped pollution right into the water.

Despite the river’s transformation from a seaside water course into a strong-smelling industrial waste channel, far-seeing landscape architect Charles Eliot saw that it could become Boston’s most prominent park. As the landscape architect for the Massachusetts Metropolitan Park Commission from 1892 until his death in 1897, Eliot said the Charles River was “destined to become the central ‘court of honor’ of the Metropolitan District, and “lobbied hard” to create a fresh water basin at the mouth of the Charles, according to the Esplanade Association’s history of the Charles River. After Eliot died, banker and former Harvard crew team captain James J. Storrow convinced legislators to finally finish the job and make the Charles River fresh forever by damming it in 1910.

Charles River Dam, built in 1978

But sometimes a river feels not so fresh. The mills closed, and many dams were abandoned, but in the 20th century the Charles started suffering from another problem; raw sewage. More people moved to the suburbs along the Charles, and local sewage treatment simply failed. As the Charles River Watershed Association writes,

“By the mid-1960’s the river was in sorry shape after several years of lower-than-average rainfall. Raw sewage flowed from outmoded wastewater treatment plants. Toxic discharges from industrial facilities colored the river pink and orange. Fish kills, submerged cars and appliances, leaching riverbank landfills, and noxious odors were routine occurrences.”

Over the next two decades, the Charles River started turning around (well, it still flowed downstream). The Charles River Watershed Association (CRWA) was founded in 1965 to clean up this mess. Strangely enough, that was also the first year the Head of the Charles Regatta was held by members of the Cambridge Boat Club. I cannot confirm that the CRWA was founded in response to the foul conditions for the Regatta, but I do wonder.

Gentle Giant Rowing Club, photo from the Boston Globe

The CRWA was energetic from the start, but it had a lot more success in getting sewage plants and industrial polluters to stop fouling the river after the federal Clean Water Act was passed in 1972. In 1974, the Army Corps of Engineers started to protect the Lower Charles from flooding by buying wetlands in the Upper Charles River, eventually acquiring 8,103 acres in Massachusetts. The final push to get the Charles River cleaner came from the Conservation Law Foundation, which sued federal and state officials in 1983 to force them to clean up Boston Harbor. You can’t clean the harbor if there’s sewage coming downstream, so state was compelled to start cleaning up Combined Sewer Overflows (CSOs.)

CSOs are very simple structures that have terrible effects. In older sewer systems, the same pipes that carry sewage to wastewater treatment plants also carry storm water away from streets when it rains. If it rains too much, the pipes can’t handle the water, and the overflow goes into a CSO… and straight into the nearest pond, river, or stream. In his recent Boston Globe piece on the Charles River’s recovery, columnist Derrick Jackson writes:

“For recreational kayaker Roger Frymire, a paddle between the Museum of Science and the BU bridge 14 years ago was disgusting. ‘I passed under the Longfellow bridge and I started smelling something awful. I kept following the smell upriver until I went under the Mass. Ave. bridge. I traced the smell to a spot near the MIT crew house. There was a grate underwater that was bobbing up and down with turds.’

That’s what a CSO smells like. Frymire found 40 discharges just like that between the Watertown Dam and the Museum of Science. Frymire, the Charles River Watershed Association, the Environmental Protection Agency, and dozens of other people have worked since 1988 to get CSOs on the Charles shut down, and it’s worked; by 2013, it’s projected that annual CSO discharge into the Charles will be one half of one percent of 1988 levels.

You may not have noticed how much the river has improved, but the fish have; shad are returning to the Charles River where they haven’t lived in significant numbers since 1850. The Charles River Watershed Association is stocking them, to give the wild fish a bit of company; the Association estimates the Charles could support 30,000 shad, as long as they keep away from Boston fishermen.

This year, the Head of the Charles Regatta anticipates 300,000 spectators watching 9,000 competitors rowing close to 2,000 boats. There will be plenty of people at the finish line, but no vaccinations–and probably no shad. If I were a fish, I’d head for the Upper Charles until all the boats, the crowds, and garbage-eating gulls are long gone. Personally, though, I haven’t acted like a fish in the Charles since my last Raft Race, so I’ll try to get there and see the lovely river in its beautiful, clean, completely unnatural state.

Meg Muckenhoupt is the author of Boston’s Gardens & Green Spaces. For more information about the Head of the Charles Regatta, scheduled for this Saturday and Sunday (October 22-23), see this blog post from the 2010 Regatta. Information is all the same, just swap in those 2011 dates!