Tattenhall and District Modified Neighbourhood Plan - Regulation 16 consultation

Comment

Representation ID: 17187

Received: 09/07/2026

Respondent: Welsh Water

Thank you for consulting Dwr Cymru Welsh Water on the Tattenhall & District Modified Neighbourhood Plan 2025 – 2045 Regulation 16 consultation. We appreciate the opportunity to engage in the Neighbourhood Plan process, and we offer the following representation for your consideration. Please note that we are the statutory undertaker for foul drainage in Tattenhall; however, we are not responsible for potable drinking water supply in the area.

Policy 4: Local Facilities we welcome that the policy states that proposals for development will be required to identify their likely impact on local infrastructure, services and facilities and to demonstrate how any such impacts will be addressed, in accordance with the provisions of Local Plan (Part One) Policies STRAT 11 (Infrastructure).

Policy 7: Site Allocations identifies a proposed new housing allocation for 600 homes at Frog Lane. We are pleased that the policy specifies the requirement for early engagement with wastewater providers to ensure that site constraints and capacity are appropriately addressed.

Sewerage Network: Adequate drainage infrastructure is key to ensuring new development sites are sustainable, viable and deliverable. Given the size of the proposed allocation, the developer would be required to undertake a Hydraulic Modelling Assessment (HMA) of the sewerage network. Once commissioned and completed the HMA would identify suitable connection points and/or the necessary reinforcement works required to the public sewerage network to accommodate the development (for example upsizing sewers, additional storage tanks etc). Developers would be strongly recommended to fund investigations at pre-application stage. Should the HMA establish that reinforcements are required to the network costings would be provided to the developer at detailed design stage. The developer would need to fund a scheme by way of the requisition provisions of the Water Industry Act or via a legal/commercial agreement with Welsh Water. The delivery of any necessary reinforcements to the sewerage network can controlled by including a suitable worded condition on any future planning permissions granted.

Alternatively, developers could also explore if the removal of surface water flows from the public sewerage system could offset the new foul flows from the proposed development. This approach could release capacity within the sewerage network for further development; we would welcome early engagement with the site developer.

There are existing sewerage assets crossing the site (125mm diameter pressurised rising main sewer, 225mm & 300mm diameter foul sewers, and 150mm diameter surface water sewer) and protection measures in respect of these assets will be required, usually in the form of an easement width or in some instances a diversion.

Wastewater Treatment Works (WwTW): The WwTW serving the village of Tattenhall does not have sufficient capacity to accommodate a further 600 homes, as such additional capacity would need to be created at the WwTW to accommodate this level of growth.

Welsh Water’s capital investment is undertaken through a five-yearly Asset Management Plan (AMP) programme. The AMP8 programme is currently being delivered which covers investment for the period 2025-30, this will be followed by AMP9 for 2030-2035, AMP10 for 2035-2040, and AMP11 for 2040-45.

Welsh Water is required to put forward a business plan for investment for each AMP cycle. Funding for capital investment is raised through customers’ bills, therefore, to ensure that customer’s money is invested appropriately we require some certainty in terms of growth areas and site development proposals. An adopted Local Plan with allocated growth helps strengthen the case Welsh Water can put forward to our regulator Ofwat in relation to WwTWs requiring AMP funding. Given the Cheshire Local Plan & Neighbourhood Plan is anticipated to have a timeframe to 2045, infrastructure investment required at Tattenhall WwTWs may be considered for delivery in future AMPs.

If a development site comes forward in advance of any confirmed AMP investment, the developer would need to undertake a Developer Impact Assessment (DIA) to establish the reinforcement works needed at the WwTW to accommodate their site. There are provisions available for developers to make financial contributions to secure the necessary reinforcements, subject to the outcome of a DIA. If there is a future AMP scheme planned to provide the required capacity, then a suitably worded Grampian style planning condition can be included on planning permissions to control occupation of development to the delivery date of the WwTW scheme.

Tattenhall WwTW is located to the north-west of the proposed allocation, and the proposed allocation would bring residential properties in closer proximity to the WwTW. As such we would recommend that the Local Planning Authority discuss the potential allocation with their Environmental Health Department to establish whether there is the potential for odour nuisance for future residents.