Although rainwater harvesting has its disadvantages, the overall system is an effective way to conserve water. As a group, we've learned that the negatives of such a project does not outweigh the positives and benefits one can reap after constructing a rainwater harvesting system. A summary of the advantages and disadvantages are listed below. (11)
Advantages
- It’s easy to maintain. Maintenance for a rainwater harvesting system requires very little time and energy.
- It reduces water bills. Water harvested can be put to many functions including drinking and non-drinking such as irrigation. Harvesting water can lead to large reduction in utility bills such as the water and energy bill for houses, small businesses, and even at the industrial and commercial level.
- It can be used for irrigation. Because rainwater is free of any chemicals that can be found in groundwater, it is the perfect choice to use for irrigation and landscaping.
- It can be used to control fires. Having large storage tanks that contain harvested water are great in areas known for forest fires as the tank is a readily available water source
- It can reduce floods and soil erosion. It can reduce pesticides from fertilizers that lead to run off water which results in cleaner lakes.
Limitations
- The rainfall is unpredictable. Precipitation is extremely difficult to predict and sometimes no rainfall is supplied meaning the system can’t harvest water.
- Initial Costs. The costs of such system can sometimes take anywhere from 10 to 15 years to see any profit.
- Maintenance. While the time and energy might be small these systems can be prone to algae growth and mosquitoes. Thus, this requires regular maintenance of the systems.
- Roofs. The roofs of buildings are the catchment area for most harvesting system. Depending on the roof type, they could allow for unwanted chemicals and animal droppings to enter the system
- Storage. The storage is the highest cost of harvesting systems. There is also the fact the sometimes harvesting systems may not be able to hold all the water that the roofs catch leading to some of the water to enter drains and rivers.