Holy roads, Batman

London's streetscape changes, exhilaratingly, from day to day. New buildings go up; new roadworks take you to excitingly unfamiliar routes; new potholes form. The streets have an entire tectonic system of their own.

I've been keeping my eye on this growing monster on Waterloo Bridge. It's on the northbound side, near the north end, by the bus stops. It's been patched and filled before, but it's a losing battle. The rock-cracking temperatures of the Snow Events last week, and the sledgehammer bus wheels, keep quarrying away at the Waterloo lithosphere.

It's a whopper! An opencast mine. An extinction-event crater. A rift valley lined with fossils of uncharted taxonomy. It took me five minutes just to clear out the geology field trip from inside it, so I could take a picture.

Well, it's quite big, anyway. Large enough to drown a small mammal in, at least. And I've reported it.

You can report this sort of thing online quite easily. The CTC have a pothole site for example, fillthathole.org. Alternatively, FixMyStreet.com is another high-tech general-purpose reporting website, and allows you to upload photos (always a help).

FixMyStreet also apparently offers an iPhone application: point the iPhone camera at the pothole, fill in a short form, and the iPhone's GPS senses where you are and which council area you're in, and magically sends the complaint with the photo to the relevant officer in the council. Then creates a Facebook group and organises a party to celebrate.

However, according to people who know about these things on Southwark Cyclists' e-group, you're likely to get quickest action on a 'red route' (controlled by Transport for London, usually denoted by red instead of yellow lines at the side) if you report it directly to the TfL website - otherwise it might go to the council instead and involve a delay.

It's a shame the road is so busy, as otherwise it could provide untold adventure-leisure opportunities - boating, bungee jumping etc. Though actually, maybe cycling over Waterloo Canyon is enough of an extreme sport, thanks very much.