You sometimes see people in city centres cleaning the windows of office blocks using a glorified fishing pole, The absurd length of the pole always makes the process look like a lawsuit in the making, as the pole flexes and threatens either to crown some passer by or smash a window and shower those below with high-speed shards.
A related problem exists for householders in that gutters get blocked (with leaves, slate dust, nests and other aerial crud). Usually, the worst blockages occur in places where it’s hard to get ladder access and you start looking at the terrifying costs of a roofing contractor and his scaffolding.
So today’s invention is a pair of extensible poles of the window cleaning type, long enough to reach roof gutterings of only domestic properties. These would be run in parallel with one pipe connected to a high pressure water hose; the outlet nozzle pointing downward into the gutter. The upper end of the second pipe would have a scoop into which the first would wash debris, before allowing it to become an immovable blockage.
This would avoid washing dirt into the normal downpipe and blocking it, whilst also monitoring the amount of crud dislodged.
Update: someone else’s solution to the problem is now available here.