QUESTIONS TO MAYOR/RESPONSES - ADDITIONAL PHOTOGRAPHS
Flooding 26 August to 4 October, 2020
Flooding early January, 2021
Flooding 14 January, 20
A close examination of one of the photographs used in the video and measurements on site reveal that the maximum water level was at least 83cm above the open grille covers on the two outlet chambers
The flooding in Marden Quarry Park was reported to NTC in early January but no action was taken until 21/22 January after Northumbrian Watet Ltd (NWL) complained that access to its pumping station (undergoing major modification) was restricted by flood water. The blockage was cleared by NWL and later claimed by NTC to have been caused by 'tree roots' in the pipe running from the lake outlet to its connection with that in the adjoining (scout hut) land pipework owned by NWL. A similar clearance of 'tree roots' by contractors was carried out on 30 August, 2019 and I witnessed the huge increase in flow that followed with the leader of the group that had done the work.
Experienced drainage contractors advise that 'tree roots' will continue to grow and cause further blockage with an accumulation of material entering the pipe, as is occurring in Marden Park. One solution is to replace the blocked pipe run. A less expensive solution is to line the pipe; but this will not stop the more frequent flooding due to floating lake debris (leaves and twigs etc.) blocking the lakeside outlet grille. A solution to this is to use a floating boom with a suitable length and draught, located a few metres from the outlet grille, as already suggested.