Water Cycle Study - East Devon District Council

Executive summary
Introduction
Ref EWCS April 2010
Exeter and East Devon Water Cycle Study
The Proposed Changes to the draft Regional Spatial Strategy for the South West propose delivery by 2026 of
around 28,500 new homes within the Exeter and East Devon New Growth Point (NGP) and 5600 homes across
the remainder of East Devon.
The NGP Steering Board appointed Halcrow Group Ltd to undertake this outline Water Cycle Study (WCS) to
support the growth point status and provide an evidence base to inform the preparation of the Local
Development Frameworks (LDF) and Core Strategy of Exeter City Council, East Devon District Council and an
Area Action Plan for Teignbridge District Council.
The purpose of the Water Cycle Study is to ensure that the proposed growth targets can be met without
adversely impacting on the water environment and that required water services infrastructure can be planned
for and brought online alongside new development, in a timely and phased manner.
Background
The vision of the NGP Steering Board is to realise the full economic potential of Exeter as a major regional
centre, providing a range of employment opportunities in conjunction with a self sufficient new community.
Opportunities for growth within the Exeter city boundary are strongly constrained spatially and as a result key
elements of housing and employment are to be allocated at East Devon and an urban extension within
Teignbridge.
The NGP Steering Board aspires towards water neutrality, whilst meeting EU framework targets on water
quality and ensuring sustainable flood management over the longer term through collaborative planning and joint
working with developers and key partners. The large scale of new growth proportional to the existing
population will present a significant challenge to meeting the NGP’s aspiration towards water neutrality.
The effect of development on the water environment forms a key part of the Sustainability Appraisal (SA) and
Strategic Environmental Assessment (SEA), required under the Local Development Framework (LDF) process.
As part of the Core Strategy, a WCS gives planning authorities a robust evidence base to assess development
impacts and to inform the debate over appropriate allocations, phasing of development and developer
contributions.
The water cycle
More development means more potable water demand, increased flows to wastewater treatment works and a
greater risk of flooding as rainwater runs off new houses driveways and roads. Human manipulation of the
natural water cycle can result in negative impacts on the water-related environment, which can indirectly affect
the ecology that is dependant on the natural features of a water cycle.
The study area features important riverine and estuarine habitats including the Exe Estuary (SSSI, SPA & Ramsar
site), the Otter Estuary (SSSI) and the River Axe (SAC). The Exe estuary is considered to have elevated nutrient
levels due to the inputs from WwTWs and diffuse agricultural sources within the catchment. Due to these
elevated nutrient levels, the estuary may be vulnerable to biological instabilities in the future if a nutrient
concentration ‘tipping-point’ is reached.
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