Blocked gully pot

The gully pot immediately west of the drive into 1 Nunwell Cottages is full to the top. The ditch upstream (east) of our drive was cleared recently (although material dumped on the verge is already falling back in - why can't this be removed from site?) and we keep the culvert under our drive clear. There is an outflow from the gully pot into a culvert under the road and into a ditch on the north side but the water can't flow through. Instead it flows down the road, scouring the tarmac and can potentially be icy and hazardous in very cold weather. I mentioned the blocked gully to the contractor when they were here recently (9th Jan I think) but while they acknowledged this would cause problems they were unable to do the work as it wasn't on their works ticket. I'm afraid we are unable to clear the gully pot out as the cover is too heavy to lift. Other works to ditches here with grips cut, are ineffective due to the direction and location of the water flow down the road. Thanks.