Typically rainwater harvesting systems consist of a catchment area, a treatment process, a storage tank, and piping to the intended use, as shown in . For most domestic rainwater harvesting systems the catchment areas consists of the roof. The treatment, size of the storage tank, and the building’s extensiveness of the piping system all depend on the final use of the rainwater’s rainwater. Figure 17: Rainwater Harvesting System (Zhang, 2008) There are a variety of ways to ensure water quality of rainwater. A very common feature of a treatment system is a first flush device. A schematic of a first flush diagram is shown in . The device works by filtering the rainwater to separate debris, and then storing this runoff in a chamber, allowing contaminants to settle and be released through a small hole in the bottom. The cleaner water at the top of the chamber is allowed to flow to the storage tank (Cross and Duncan, 2007). This device prevents larger debris from entering the storage tank. Figure : First Flush Device (Cross and Duncan, 2007) After the water is filtered by a first flush device it is stored in a tank. The size of the tank greatly affects the economic feasibility of the system, as the cost of tank installation tends to be the largest component of rainwater harvesting cost (Chilton et al, 2000). Therefore when designing a rainwater system’s harvesting system it is very important to size the storage tank correctly. The quality of rainwater collected also needs to be monitored if it is to be used for drinking. This is because rainwater can be contaminated with microbes,
Typically rainwater harvesting systems consist of a catchment area, a treatment process, a storage tank, and piping to the intended use, as shown in . For most domestic rainwater harvesting systems the catchment areas consists of the building’s roof. The treatment, size of the storage tank, and the extensiveness of the rainwater’s piping system all depend on the final use of the rainwater. Figure 17: Rainwater Harvesting System (Zhang, 2008) There are a variety of ways to ensure water quality of rainwater. A very common feature of a treatment system is a first flush device. A schematic of a first flush diagram is shown in . The device works by filtering the rainwater to separate debris, and then storing this runoff in a chamber, allowing contaminants to settle and be released through a small hole in the bottom. The cleaner water at the top of the chamber is allowed to flow to the storage tank (Cross and Duncan, 2007). This device prevents larger debris from entering the storage tank. Figure : First Flush Device (Cross and Duncan, 2007) After the water is filtered by a first flush device it is stored in a tank. The size of the tank greatly affects the economic feasibility of the system, as the cost of tank installation tends to be the largest component of rainwater harvesting system’s cost (Chilton et al, 2000). Therefore when designing a rainwater harvesting system it is very important to size the storage tank correctly. The quality of rainwater collected also needs to be monitored if it is to be used for drinking. This is because rainwater can be contaminated with microbes,
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