Anamitra Khan, General Manager – Operations, Green Systems Ltd, New Delhi, explains the concept of water sensitive urban design (WSUD) which is a smart and effective approach to managing groundwater, wastewater and water supply in an urban environment.
Water sensitive urban design (WSUD) is an approach to the planning and design of urban environments that supports healthy ecosystems, lifestyles and livelihoods through smart management of all our waters. Water sensitive urban design also leads to land planning and engineering design approach which integrates the urban water cycle, including stormwater, groundwater and wastewater management and water supply into urban design to minimise environmental degradation and improve aesthetic and recreational appeal.
WSUD looks to manage the impact of stormwater from development. It works at all levels – at the lot level, street and precinct level, as well as regional scale – with the aim of protecting and improving waterway health by mimicking the natural water cycle as closely as possible.
The necessity for water sensitive urban design applications in India is quite high due to urban sprawl and lack of planning. Even rural India is seeing new opportunities in agricultural segments with innovative technologies and subordinate irrigation systems. The need of WSUD therefore belongs to the entire society and can be developed on a vast term as well as regional and local applications.
In terms of growth of industries and rapid commercialisation, there will be a clinch of natural resources due to indiscriminate use of those integral parts which not only destroy the micro and macro-habitats but also in long run affect human life badly. The question arises as to what could be the answer to this situation. Hence, the concept of WSUD has been adopted worldwide.
Water sensitive urban design is an approach to urban planning and design that integrates the management of the total water cycle into the urban development process. It includes:
- Integrated management of groundwater, surface runoff (including stormwater), drinking water and wastewater to protect water related environmental, recreational and cultural values;
- Storage, treatment and beneficial use of runoff;
- Treatment and reuse of wastewater;
- Using vegetation for treatment purposes, water efficient landscaping and enhancing biodiversity;
- Utilising water saving measures within and outside domestic, commercial, industrial and institutional premises to minimise requirements for drinking and non drinking water supplies
Key principles of WSUD
- Protect waterways
- Protect waterways within urban developments so that they can remain valuable community assets that enhance livability and support the ecosystems that rely on them.
- Manage storm water in the landscape.
- Manage storm water in the landscape rather than drain it all to waterways. This reduces the volume and frequency of storm water drained and increases the quality before storm water reaches waterways.
- Add multiple benefits while minimising development costs
- Provide for a range of benefits such as alternate supply, improved amenity and safety, and contribute to enhanced livability by enhancing natural features such as rivers and lakes. WSUD minimises the drainage infrastructure development costs by reducing pipe sizes and potentially replacing other large scale reticulated water systems with local solutions.
Key applications of WSUD
WSUD applications can include a range of applications, including grassed or landscaped swales, infiltration trenches and bio-retention systems, gross pollutant traps, wetlands and sediment ponds, rainwater tanks – stormwater harvesting and reuse, grey water harvesting and reuse, rain gardens, rooftop greening and urban forests, porous pavements, and aquifer recharge and reuse.
Now, India also has advanced technologies to offer the best solutions in terms of stormwater management, aquifer recharging, grey and freshwater harvesting, water treatment facilities and landscaping solutions in an integrated manner so as to provide specific solutions towards achieving water sensitive urban designing processes.
- Individual site conditions and catchment characteristics (e.g. location, geography)
- Building function and occupancy (e.g. residential, commercial, industrial)
- Development or redevelopment scale and type (e.g. greenfield, brownfield, infill)
- Water use and demand (e.g. garden irrigation demand, industrial use etc.)
- Water sources available, including local climate (e.g. rainfall seasonality)
- On-site catchment area (e.g. roof and surface)
- Urban landscape design (e.g. architectural and landscape)
- Greenhouse gas emissions
In few of the areas, this has been adopted; for instance, a very large PSU in Madhya Pradesh has planned to install drip irrigation network throughout the golf course to reduce water consumption and make it water effective after doing complete watershed management consultancy and water audit.
A large automobile industry in Haryana made has become water positive by adopting rainwater harvesting for recharging the aquifer and also recharging through water body development after doing water resources management consultancy.
Many commercial buildings and residential complexes are adopting energy efficiency through energy audit and energy efficient lighting, and solar hot water supply using rooftop solar power.