Sorry, don't read any further if you actually think the answer will be contained within. You will be surely disappointed. I had my first Council surgery yesterday with one taker which was a bonus since it hadn't been advertised. The issue raised was the long awaited 20mph zone in West Street, Carshalton. This has been on the agenda for a number of years but has failed to materialise. I noticed that on the list of items that Sutton Council produce each year to bid for funding, the 20mph zone had disappeared. It was confirmed that this was because the funding was there so no more excuses.
The existing plan, however contains speed bumps to help slow the traffic. These are all situated outside houses that are very close to the road so you can imagine those residents are not happy. There has been one fatal accident and one near-fatal accident in the last few years so something needs to be done. There is agreement in this but not in the method.
West Street is very narrow but is nonetheless an arterial road out of Carshalton. The £150k disaster of the speed bumps in Woodmansterne Road should teach us something. There are alternatives. Flashing signs, speed cameras, signals, something but let's not just get the navvies in to dump their excess tarmac without giving it just a little thought and, surprise us, just a little consultation. I shall certainly be asking everyone what they want. (Feel free to leave a comment here, though it would help to state if you were a resident or not.) Anyway, I have started you off with alternatives in my suggested sign above.