How does that old song go? 'When the weather is fine you know it's the time...For messin' about on the river'. Actually, it's the time to sort out the mess on the river, as Thames21 announce their spring/summer programme of volunteer days. All you need to do is email the listed person here, and turn up in old clothes. They'll provide all equipment. Most events are open to families, but children under 16 must be accompanied by an adult.
Some highlights below - you can find further details and dates on the Thames21 web site.
Fri 30 April, Isle of Dogs foreshore cleanup, 9-11.30am
Sun 2 May, Battersea foreshore cleanup, 11.20am-2.pm
Sat 8 May, Thamesmead river cleanup, 9-11.30am
Tue 1 Jun, Galleon Lake, Thamesmead cleanup, 12-3pm
1-13 Jun, Three Rivers cleanup (Ravensbourne river)
It's not all about cleaning. Thames21 also organise many activity days where you can enjoy London's waterways. Again, see their site for more details.
Image by thegirlg in the Londonist Flickr pool.