From low flush toilets to sustainable urban drainage systems we take a look at some of the water saving measures currently available.
Every day a person uses on average 150 litres of water, of this 50 litres is for WC flushing, representing 35% of all household consumption. To help minimise the impact on scarce water resources and to alleviate the increasing environmental problems of flooding and pollution associated with traditional urban drainage systems, it is important to take greater control of water use and disposal and to implement sustainable water conservation and drainage systems.
The following measures can drastically reduce the amount of water we consume:
The installation of low flow appliances such as supply restrictor valves, low flow showerheads, spray taps and dual flush toilets.
There now exists complete washroom control systems for the non-domestic market that regulate water supply, lighting and ventilation, supplying services on demand. Advantages include: minimal additional build/installation cost, up to 40% reduction in water usage for user, an additional selling point for developers.
Directing all roof run-off via water butts.
Advantages include: minimal additional build cost, reduced ‘peak-flow’ surface water run-off and ready supply of water for irrigation purposes.
Grey water recycling through reusing the water used in washing for toilet flushing.
Advantages include: significantly reduced water consumption and additional selling point for developers.
Sustainable Urban Drainage Systems
SuDS is an approach to managing surface water run off absorption into the ground as close as possible to the point where the rain falls. SuDS are being promoted by many organisations (including the Environment Agency and SEPA) and through government guidance (e.g. PPG25 Development and Flood Risk) to encourage their widespread use as an alternative to traditional piped drainage systems and as a means of reducing flooding, reducing pollution, conserving resources and creating habitat.
SuDS are a flexible series of options that allow a designer to select those that best suit the circumstances of a particular development. It is essential that these issues are considered at the earliest point of the design stage. A basic summary of the main components and their advantages over traditional drainage systems are as follows:
The use of permeable hard and soft surfaces, such as block and sand, gravel, grasscrete etc to aid water absorption.
Advantages: reduced peak flows to watercourses, filtration of pollutants, reduced need for deep drainage excavations, tailored so that construction costs suit the proposed usage and design life and costs are comparable to, or lower than, conventional surfacing and drainage solutions.
Installing Green or Brown Roofs comprising growing medium plus grasses, Sedums etc.
Advantages: regulates and reduces water run-off, improved aesthetics, improved insulation values, reduced particulate pollution, improved biodiversity, minimal maintenance, up to 25 year guarantee.
Infiltration trenches and basins – excavations that have been back-filled with stone to create underground reservoirs that gradually infiltrate into the subsoil.
Advantages: costs are comparable to or lower than traditional piped systems, pollution filtration and replenishment of groundwater supplies.
Retention ponds- where large non-permeable hard surfaces are unavoidable, such as substantial road provision. Advantages – acts as buffer at peak flow times and can offer wetland habitat creation opportunities and a recreational facility.
