Constructor damage to pipeline at Sainsbury’s site, North East Hook
The Whitewater Valley Preservation Society (WVPS) expressed concerns when the development of 500 houses on a site in North East Hook, adjacent to the roundabout on the A30, was first considered by Hart District Council.
The main reason for our concerns was the fact that the entire site sits on a slope (the West side of the river valley) which exposes the river not only to run-off from construction but, once built and sold, problems with the sewage generated by the site, given the lie of the land.
During the construction phase, there were indeed incidents of pollution to the river, despite assurances from Hart, and now the entire sewage system is reliant upon pumping of effluent into tanks on the site when the Thames Water network cannot handle the flow.
Whilst touring various pumping stations susceptible to sewage discharge recorded on the Thames Water sewage discharge map, WVPS committee member John Fleming, visited Holt Lane. Here it was apparent that flooding was occurring in the field next to the River Whitewater. A Thames Water engineer informed Mr Fleming that builders on the Sainsbury’s site had damaged a sewage pipe carrying effluent to the storage tank on site. Thus putting all of the houses at risk of flooding with sewage effluent from the damaged pipeline.
The only solution available to Thames Water was to divert many tankers to the location of the damaged pipe, to collect the effluent and transport it to the Holt Lane storage tanks.
Holt Lane pumping station links into the system leading to Hartley Wintney treatment works, but at times of heavy rainfall, the system is overwhelmed and effluent must be stored until capacity is available.
Since Holt Lane is known to need tankers to avoid having to discharge into the river, in these heavy rainfall conditions, the problem at Hook will inevitably lead to discharge into the Whitewater.
WVPS Chairman, Candy Burnyeat, and Mr Fleming feel this is sufficiently important for members to be informed and to write to the new Chief Executives of Hart and the Environment Agency.
WVPS believes there should be a full investigation into and report on the damage caused to the river, and actions proposed to alleviate the environmental impact on its chalk stream ecology.
The working of the current system and its reliance on holding tanks, especially in view of the changing climate and therefore weather patterns, should be the subject of an urgent review. There is a need to increase the capacity of the wastewater system to Hartley Wintney, thereby removing the constant danger of effluent discharging into to River Whitewater.