Still floods after rain after drain cleaned out recently

Been reported many times over 4 years. Recently a lot of mud was removed and put out of harms way in the grass. However, a heavy down poor last week saw the underpass flood again (see photos), flooded in the morning, slowly drained during the day. So some more pipe/gully clearing needed. Gullies looked at are not on your map (no green dot in the right place). One drain (plain steel plate cover) cleared (now has a red X sprayed on it) is on the outside of the sharp bend at the bottom of the map/plan. The other main gully(?) is at the end of the subway in the centre of the roundabout (very close to the bottom of the pink half face grafitti in 1 photo. While it was flooded, all the other gulleys in the middle of the roundabout were full but not over flowing. Also, after the gully clearing the other week, an awful lot of thin mud/slurry was left all over the cycle track/footway surface. Not only does this present a slip hazard to cycle users, but also means pedestrians get it all over their shoes. Could a small (to get under the subway) street sweeper be used to clear up the mess please.