Storm Water Management

Storm water management practices and strategies applicable to Western Cape. 1. Introduction Storm water management plays a very big role in local communities and all over the country. Storm water management is basically separating two kinds of water, portable water and waste water, in order to prevent pollution. In this investigation a general discussion of storm water management will be included, typical management strategies and practices of storm water management. The purpose of this investigation is to understand the methods of storm water management. The objective of storm water management practices and strategies is to improve the quality of life and to prevent health implications to humans.

2. General definitions of Storm Water Management 2.1 What are storm water management and drainage? Storm water management is the mechanism for controlling storm water runoff for the purposes of reducing downstream erosion, water quality degradation, and flooding and justifying the adverse effects of changes in land use on the aquatic environment.

2.2 What is storm water management? Storm water is the phrase used to describe the excess rainwater that flows from rooftops, roads, car parks and other buildings. This water can contain many pollutants picked up from roofs and highways. In extreme weather conditions sudden heavy downpours of rain can cause major environmental disasters. Using our Rain manager products; storm water cannot only be safely removed, but it can be stored and recycled for commercial and domestic use.

3. Storm water management facilities Storm water management facilities are those facilities, including but not limited to, storm water retention and detention ponds and Best Management Practices (BMPs), which retain water for a period of time to control runoff of storm water runoff. Detention ponds is basically referred to depressed landscaped areas used to detain storm water runoff during heavy rainstorms. The ponds fill with excess water and drain into the combined sewer system at a controlled rate that reduces the chance of sewer surcharge.

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4. Problems associated with storm water management 4.1 Combined sewer overflows Combined sewer overflows are one of the most important urban pollution sources in older parts of many areas in the world due to the fact that storm water flows often exceed the hydraulic capacity of a combined sewer system.

4.2 Sewer inflow and infiltration Inflow and infiltration of both storm water and groundwater into sanitary sewer systems is a common and difficult problem. Recent research has pointed out that sewer inflow and infiltration may actually exceed sanitary flow rates. Inflow is surface water, while infiltration is defined as groundwater that enters the sewer if the water table rises above the pipe level. Both are usually the result of rain or snowmelt. Inflow usually occurs through manholes and illicitly connected storm drains. Careful design of sewer vents and manholes can limit the amount of storm water inflow entering the sanitary sewer. Enforcement of regulations restricting impervious areas from draining into the sewer is a way to limit the amount of illicit storm water entering the sewer. Infiltration can result from storm water including snowmelt recharging groundwater which then enters the sewer through cracks and leaky sewer pipe joints. Other factors leading to sewer infiltration are workmanship, pipe materials, system age, backfill material, tree root intrusion, and vibration from overhead traffic. Infiltration is a function of groundwater elevation above the sewer leak and is usually much more difficult and costly to control than inflow.

5. General principles of storm water management? Good quality storm water management is based on the separation of portable and wast water therefore includes the basic principles of pollution prevention. Water quality requirement is also used for the determination of portable and waste water. According to the book Best Practices Guideline H3 (DWAF, 2007) storm water management often fails to meet its objectives, because the designer does not take into account the wider issues, which are the management and implementation issues.

5.1 Primary Principles The following information is according to the book storm water management (DWAF, 2007) • Keep clean water clean Water must be kept clean and transported by a system to prevent portable water mixing with the waste water • Collect and contain waste water The waste water must be contained in a system separate from the portable water

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Sustainability over mine life cycle This is related to the storm water management plan, such as waste management facilities Consideration of regulations and stakeholders. Regulations must be measured and included to support in the function of the primary principles above.

6. Conclusion Storm water management is mostly concern with the development of water facilities and improving health effects of humans. If guidelines are not set it could result in disasters. According to this study it was found that storm water management must have a plan that is known as the storm water management plan (SWMP). The SWMP must have its own regulation and standards, so that storm water can be manage in a safe and proper manner. In general this research has focused on a more theoretical part of what is storm water management and what is needed to manage storm water.

7. Referencing www.wetlands.com/pro/fr21jul99pte.htm http://www.ene.gov.on.ca/cons/4328e.pdf

Book: Storm Water Management, DWAF, 2007

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