Stormwater Runoff
Historically, conventional drainage was designed to remove rainwater, as quickly as possible from the point at which it has fallen, to a discharge point. As population and developments grow, this approach has a number of damaging results.
Conventional Drainage Issues
Surface Run-Off - Surplus water from hard paving and roofing can significantly increase the risk of flooding downstream as well as causing sudden rises in water levels and flow rates in watercourses.
Contamination - Surface water run-off potentially contains contaminants such as oil, organic substances and toxic metals. Cumulatively, at low levels, they can generally cause poor water quality in rivers and groundwater, affecting biodiversity, amenity value and potential water abstraction. After sustained periods of dry weather, heavy rain can cause the first flush to be highly polluting.
Water Courses - By capturing rainfall in piped systems, water is prevented from soaking naturally into the ground, depleting ground water and reducing flows in aquifers and watercourses in dry weather. As a direct consequence many urban watercourses are lifeless and unattractive, and are often hidden in culverts under the ground.
Our Solutions for Conventional Drainage Issues
Addapave TP AddasetInfiltration - Infiltration is governed by two forces, gravity and capillary action. Smaller pores offer greater resistance to gravity, very small pores pull water through capillary action in addition to and even against the force of gravity.
The rate of infiltration is affected by surface characteristics including ease of entry, storage capacity and transmission rate through the soil.
Attenuation - Modern building and agriculture methods often mean that water, falling as rain or formed from melting ice or flooding, cannot return to the ground to form groundwater. Instead, it often flows away from the locality where it is generated, depriving the ground of its beneficial effects and overflowing normal drainage systems, leading to flooding, erosion and general disruption to the environment.
Providing attenuation systems which lengthen the period during which water is held at a location where it arises, e.g. at a storm area, for dispersal into the ground at that area without flowing away, is one solution.
