Surface storm water management solutions should be integrated into the overall design and planning of an area and involve a multidisciplinary team of professionals. This addresses technical and aesthetic issues in all design phases. Consider maintenance requirements in the design and budgets in order to guarantee performance and quality.
Combine water management solutions with the need for recreation and nature in the city, and introduce other green city solutions such as green roofs and green streets. Be sure that the solution appropriately meets land use. Make stormwater visible in the design of public and private open spaces. Water features add to the amenity value of urban public green space. Create ways to not only buffer water but also to use in times of drought.
All newly paved surfaces should be compensated by extra open water which equals at least 10% of the paved surface area.
Trees are very effective at slowing runoff. They intercept peak rainfall, improve the infiltration capacity of the soil, and can improve the quality of the water that is buffered. Trees can bring groundwater up to the surface where some evaporates, and the soil is kept moist. Conifers are 3x more effective than deciduous trees.
Biofiltering wetlands can be designed as functional and aesthetic solutions to surface water pollution. As water gradually filters through the plants into a series of basins, pollution sediments settle to the bottom. Careful attention to plant selection is essential.
Solve runoff problems closer to the source in urban areas with surface storm water management instead of draining all the water into the sewer system.
|harvesting||above or underground cisterns||rainwater use||fountains, pools, etc|
|bioretention||shallow landscaped depressions which drain by filtering through the vegetation and soil||water treatment||landscaped element|
|biotopes||ecologically stable landscape of plants and animals||water treatment||wetland, biofiltering wetlands|
|gravel/sand filters||above or below ground chambers to treat runoff||water treatment||edging along green spaces, channels, buildings|
|rooftop retention||extensive or intensive green roofs or brown roofs||detention + infiltration||green roofs|
|permeable paving||paving that allows water to pass to a gravel subgrade where it can evaporate, infiltrate or be drained||detention + infiltration||parking areas, paved areas|
|infiltration zones||planted areas with layers for retention, filtration||detention + infiltration + infiltration||open spaces trenches and parks|
|swales||linear planted drainage feature which allows water to travel downstream or infiltrate||detention + infiltration||open spaces and parks|
|geocellular systems||prefab underground structures to store and slowly infiltrate water||detention + infiltration||use in high density urban settings|
|detention pond (dry)||surface storage basin holds storm water and slowly drains and settles particulates (otherwise dry)||detention + infiltration||landscape and recreational uses|
|detention pond (wet)||surface storage basin stores/holds rainwater and circulates through other treatment techniques||detention + infiltration||ponds, lakes, recreation|
|channels||open storm water channels instead of sewerage||conveyance pipes underground||channels, streams, canals|
|passive||all green spaces with vegetation evapotranspiration||evapotranspiration||urban green spaces, gardens|
|active||use water to directly influence temperature or evapotranspiration||evapotranspiration air quality||rainwater walls, pools, fountains|
In new development:
Consider surface storm water management needs and solutions from the beginning of the planning and design process in order to provide the best integrated solutions for future runoff.
In existing development:
Reduce the area of impervious surfaces by replacing them where possible with the surface stormwater techniques (see next page) based on size, capacity, budget and surrounding development.
Conifer trees used in the Netherlands:
Abies, Picea, Pinus, Pseudotsuga menziessii
Deciduous trees used in the Netherlands:
Acer, Aesculus, Fagus, Quercus, Tilia, Ulmus
Plants used in biofiltering wetlands in The Netherlands
Lysimachia nummularia, Sagittaria sagittifolia,
Phragmites australis, Carex, Menyanthes trifoliata,
Pontederia cordata, Sparganium emersum
Combining the use of native plants and biofiltering capacity in landscapes, research in Australia provides a list of plants and their suitability and tolerance for managing water runoff.
Biofilter vegetation guidelines