BRIDPORT'S sewer system has been deemed 'very high risk' of being incapacitated during flooding - and is unable to cope with demand from new developments.

That's according to Wessex Water, which manages Dorset's sewer systems. The issue of sewer incapacity has been brought to light after recent flooding and heavy rain saw raw sewage discharged at swimming spots in the sea and rivers along west Dorset's coastline, including at West Bay and Charmouth.

Under heavy storm conditions sewer capacity can be exceeded and built in safety valves, called storm overflows, permitted by the Environment Agency, can operate to prevent sewer flooding.

According to Wessex Water the Bridport area has very risk for sewer incapacity, and there are frequent storm overflows.

Wessex Water is following a methodology to investigate and make improvements - however the company has warned that new developments proposed in Dorset Council's Local Plan are likely to put additional pressure on the system - and that upgrades will be needed to the sewer infrastructure, paid for by developers.

A Wessex Water spokesman said: "Development at Vearse Farm, Bridport is promoted through the plan and has recently obtained planning permission for 760 new homes and approximately 4 hectares of employment land. The Joint Local Plan Review preferred options (October 2018) confirms Land at Vearse Farm “is designated to meet the long term needs of the town”. The review identifies additional sites within the original Vearse Farm allocated site which could deliver a further 170 homes.

"To support growth strategic improvements to the sewer network will be agreed with partners to accommodate growth at Vearse Farm."

New developments can also increase rainwater runoff into drainage networks, causing an increase risk in surface water and potentially sewer flooding. "We have a policy that surface water connections to the foul sewer system is not permitted," the spokesman added.

The issue of sewage being pumped into the sea and rivers has been the subject of public scrutiny after MPs, including west Dorset's Chris Loder, voted against an amendment to the Environment Bill that would have seen water companies forced to upgrade sewer networks.

Interactive maps created by charities Surfers Against Sewage and The Rivers Trust have highlighted where emergency storm overflows have been used in west Dorset.