Flooding issues in Willingham

A huge amount of work has gone into trying to understand exactly what went wrong over the Christmas period. The parish council is grateful for the considerable assistance received from our county and district councillors and, in particular, our local experts who have the detailed knowledge to ask probing questions and are part of the working group that has now been formed.

The parish council will be meeting with Anglian Water in April and they have provided the response below to our initial enquiries. A further, more detailed list of questions has been put to Anglian Water and we anticipate a response to these by the end of March.  

Anglian Water Questions and responses

  • The theoretical capacity of the main sewers in terms of population, bearing in mind that the current infrastructure was designed and installed when the village was a third of the current size?

Sewerage systems are designed to a 1 in 30 storm event rather than on population capacity. We make growth capacity assessments based on the proposed use class, the amount of flow the site would produce, the connection regime (gravity or pumped) and the connection point. We do not make it solely on the number of properties.

  • The proportion of surface water to raw sewage that they carry.

The amount of surface water within a sewerage system is weather dependent so it is not possible to say what the proportion of surface water to raw sewage as this proportion constantly changes. The majority of customers in Willingham currently receive surface water removal from Anglian Water according to our billing information. We do rely of customers telling us if they have a separate surface water soakaway/system – and would encourage any customer who has a separate surface water soakaway to inform us (as this would reduce their water bill). 

  • What plans, if any, AW have to reinforce the current infrastructure?

We currently have a scheme underway to add additional capacity at Over Water Recycling Centre (WRC) which would increase the capacity to store water from heavy rain events.

  • What capacity is left for further development in terms of population growth and whether or not this takes account of climate change?

There are currently no capacity issues predicted in the network as a result of known planned development. Anglian Water has a legal obligation to accommodate growth via treatment capacity at our water recycling facilities (WRCs) as and when it occurs. Willingham is part of the Over WRC catchment and biological capacity at Over WRC is almost double the current population equivalent served by Over WRC. Over WRC also has a storm tank scheme currently underway (mentioned above) to increase storm capacity in the WRC.  

It is also important to note that we are not statutory consultees to individual planning applications and we therefore self-monitor the 65 Local Planning Authorities in our region. We have a statutory duty to connect all new premises and we cannot reject a connection irrespective of network capacity under section 106 of the Water Industry Act. This section also states that the applicant only needs to provide us with 21 days’ notice of their intention to connect. It is therefore critical for us to monitor Planning Applications. We offer a service to our customers where, if they have concerns about a planned development, they can provide us with the planning reference and we will assess the impact. This service is provided free of charge. For each request, one of our Planning Engineers will assess the impact of the growth and provide a written report to the Local Planning Authority. You can find more information on this service on our Planning Services webpage.