Climate Change SPD
Chapter 8: Water efficiency measures
Reducing the risk of drought is crucial in adapting to a changing climate. There is a need for a significant reduction in personal water consumption.
The Environmental Improvement Plan (2023) states that sustainable drainage systems (SuDS) will become mandatory in all new developments by 2024. SuDS, which include a range of eco-friendly measures such as ponds, reed beds and shallow drainage channels, will be required in all new developments in order to reduce the risk of flooding, storm overflow discharges and pollution caused by surface water runoff.
The Colchester Water Cycle Study (WCS) concluded that, allowing for the planned resource management of Anglian Water Services South Essex Resource Zone, Colchester would have adequate water supply to cater for growth over the plan period. However, the WCS identified that there are long term limitations on further abstraction from the raw water resources supplying the Borough and that there is a drive to ensure the delivery of sustainable development for Colchester. Hence there are key drivers requiring that water demand is managed for all new development in order to achieve long term sustainability in terms of water resources.
Policy DM25 of the Section 2 Local Plan requires residential developments to meet the Building Regulation optional higher water efficiency standard of 110 litres per person per day, as set out in Building Regulations part G2. To reduce the demand for water, all development proposals should include water efficiency measures. Applicants should submit a water efficiency calculator report to demonstrate compliance with the policy requirement for 110 litres per person per day water efficiency standard. Applicants should consider reducing water use to the lower water efficiency standard of 80 litres per person per day.
To reduce water demand, water use should first be minimised through efficient fittings. Rainwater harvesting systems and water reuse systems further reduce water usage and the incorporation of these systems should be considered in all new developments.
There are simple measures that can easily be included in new buildings, and retrofitted to old, to help reduce householders' water usage often at little or no cost to the developer. For example: aerated and low flow showerheads reduce the flow and amount of water but don't compromise on pressure; dual flush toilets; A rated appliances.
A rainwater harvesting system allows residents to collect, filter and store rainwater within an underground tank. When stored underground, the rainwater captured remains clean and fresh. Rainwater harvesting also helps manage surface water. As a minimum, all homes should be provided with a water butt.
Water re-use, or greywater recycling, collects, processes and stores greywater for subsequent re-use as non-potable water, ie for toilet-flushing, clothes-washing machines, and irrigation. Greywater is the wastewater from showers, baths and wash-hand basins.
Green-blue infrastructure can contribute to making areas less vulnerable to flood risk whilst ensuring development doesn't increase flood risk to third parties. Through its key role in sustainable drainage, drought mitigation, flood and water stress reduction, providing opportunities for attenuation or infiltration that can help to recharge aquifers, and maintaining levels in watercourses or other blue infrastructure features. The incorporation of sustainable drainage systems (SuDS), that mimic natural drainage and encourage its passive infiltration and attenuation, will be required in all new developments. To avoid increased flood risk and make effective use of existing and planned drainage infrastructure, rainwater should be managed as a valuable resource rather than a waste product. A multi-functional approach to the delivery of SuDS provides multiple benefits such as the provision of public open space and increase biodiversity. The Council has adopted the Essex County Council SuDS Design Guide as SPD and development proposals should demonstrate how they have complied with this.
There is a target for 75% of water bodies to be 'good' status by 2027. Currently only 7% of water bodies in Essex are 'good' status. SuDS are important for water quality benefits and it is important that the SuDS management train or 'treatment train' is followed.
Essex County Council are preparing an Essex Water Strategy and applicants should have regard to this.
