At least near Harvard Square, the answer is "yes!" Leslee captured a group of people jumping off the Weeks Footbridge into the Charles the other day.
Posted under this Creative Commons license and in Universal Hub pool on Flickr.
Attendants stand by with syringes full of hepatitis serum, and a portable eyewash station.
http://www.crwa.org/water_quality/daily/daily.html provides daily reports of water quality, but only from July to October. And they only report if the river is safe enough for boating, which is a less strict standard than for swimming.
Is there not enough rowing traffic in the spring to justify daily water testing?
The CRWA provides the numerical data for its testing. All you need to do is click on the flagging site of interest to get the data. For safe swimming, The MA standard for fecal coliform bacteria is a threshold of 200 colony forming units per 100 milliliters (cfu/100 mL). For safe boating, the MA standard is a threshold of 1,000 cfu/100 mL. Much of the time, unfortunately not all the time, the water does meet the swimming standard, especially in the Lower Basin.
As for testing earlier in the year, I am confident that the CRWA would want to do so if you could provide the funds.
Checking out the bacteria levels on-line before a dip is a good idea. Generally, I understand that the water in the Charles has gotten much better over the years (thanks CRWA, CRC, DEP, et al!) but you might want to not swim after a big rainstorm. Additionally, the water might be improved, but that's not saying that what's in the muck at the bottom is all that safe to kick up. Lots of heavy metals and assorted ka-ka in there. Wear some old sneakers or some tevas or something.
I am both thrilled ("they think it is safe enough!") and horrified ("eeccchhhkkkk!!!").
I have gotten tetanus shots for the sole purpose of *sailing* on the Charles, but I still
confess to a secret desire to swim in it one day...
(You have to have been around here a looong time to get that one.)
There has been swimming in Charles for awhile. Don't know if you have to check the
toxicity levels for months or years to pick a date. But it has been done.
Ear infection, anyone?
I agree with these posts. It's gotten better water quality-wise. I have jumped on various occasions, and have never gotten sick. I've never touched bottom when jumping, but my taller, heavier friend claims he has. You have no idea whats down there, a bike or a bathtub or two. Don't dive!