Development Aspects Impressum Editors

Discussion and results

1. The rainwater harvesting project

The N-Park rainwater harvesting project showed that a large amount of rainwater can be harvested every month. This is because there is abundant rainfall, averaging between 200 and 500 mm per month. Hence, the lesson learnt is that Malaysia has high rainfall all year round and has great potential for rainwater harvesting. Unfortunately, however, this rich potential is untapped at the moment. Installing a rainwater harvesting system in apartments is fairly easy as most rooftops have built-in gutters and drainpipes trapping rain. The N-Park project showed that the condominium has harvested more rainwater than it could use. To use more of the harvested rainwater, it needs to be diverted to the area where washing activi- ties such as car washing and garbage bin washing take place. During every heavy rainstorm, the 10,000-litre capacity tanks would fill up quickly to the brim (table 1). N-Park is not utilizing all its harvested rainwater for several reasons. First, the PBA taps provide better water pressure and gardeners and cleaners prefer to use the PBA piped water as they can finish their chores faster. Second, there are not that many plants to water in and around the rainfall tanks area in the Block D car- parking block. Third, because of a lack of space, there are no car-washing bays utilizing rainwater in any of the four blocks. Currently, there are two car-washing bays near Block A. Fourth, the rainwater is currently only used for flushing toilets in the badminton court toilets (one male and one female). Fifth, the major landscaped

areas are located on the southern side of all four blocks while the tanks are located on the northern side. It would take extensive piping connections to link the tanks to the southern side.

2. The water-saving fittings in common area toilets

The total number of water-saving fittings installed was 101 units (table 2). The types of water-saving fitting include: dual flush cisterns; automatic push taps; and push urinals. The areas installed with such fittings were the toilets on the ground floor near to the lifts in Block A, Block B, Block C and Block D. Table 3 shows water consumption data for the entire N-Park common area. Before the launch of the rainwater harvesting project (31 October 2009) and water fittings installation (20 April 2010), it was clear that the average water consumption was very high, between 9,000 and 12,000 m³ per two months. After both systems were installed, the water consumption showed a very significant decrease. This was reflected in the May, July and September 2010 water consumption figures which averaged be- tween about 6,000 and 8,000 m³. This is a significant decrease of about 33.3 per cent. Figure 3 illustrates the trend of this significant decrease in water consump- tion. In terms of monetary savings, N-Park Condominium saved RM3,609.1 (table 4), RM3,524.7 (table 5) and RM1,249.2 (table 6) for the billing months of May, July and September, respectively. This gave a total monetary savings of RM8,383.0 over a 6-month period (April to September 2010).

Table 1: Total harvested rainfall from May to October 2010 in N-Park


Table 2: Types and numbers of water-saving fittings installed in the common area toilets in N-Park