Blenheim Stormwater Strategy - Action Plan Glossary AEP Annual Exceedance Probability. A statistical term defining the probability of an event of a given size being equalled or exceeded in any year, expressed as a percentage. For example, a 5% AEP event has a 5% chance of being equalled or exceeded in any one year. BMP Best Management Practice. Methods (programmes, systems or structures) used to control or prevent contamination of receiving environments. CMA Coastal Marine Area CSC Comprehensive Stormwater Consent. The purpose of a CSC is to consent multiple activities associated with stormwater management and discharge within urban catchments3. Contaminants Includes any substance or heat that when discharged into water or onto land, changes or is likely to change the physical, chemical or biological condition of that land or water onto or into which it is discharged. MDC Marlborough District Council Modified Watercourse A watercourse or river that has always existed in some form in the general area. However, the watercourse has been modified by engineering works to alter is original form or alignment such as, for example concrete or gabion lining, or channel straightening works. River Is a continually or intermittently flowing body of freshwater and includes a stream and modified watercourse, but does not include any artificial watercourse (including an irrigation canal, water supply race, canal for the supply of water for electricity power generation and farm drainage canal). RMA Resource Management Act 1991 Sediment Eroded material that can include adsorbed contaminants. SMAP StormwaterManagement Area Plan Stormwater Water that falls to the ground, runs off the surface into streams, lakes, marine areas or underground aquifers and includes the contaminants washed off surfaces by water. Stormwater Management A unit which represents the areas catchment (area within which Area Plan runoff is carried under gravity drainage system to a common outlet) plus, selected adjacent areas where the aspiration is for those areas to be managed by the same network or process 3 In the context of these guidelines, an ‘urban catchment’ is considered to be a defined urban area for which a CSC is sought. The defined urban catchment may be the entire urban area from which rainfall is collected and consist of many hydrological sub-catchments. It is likely to have multiple stormwater discharge points to receiving water that are located both within and beyond its boundaries. Beca // 28 May 2009 4260171 // NZ1-1630756-12 0.12 Page 107