In the summertime, drinking water is a precious resource that's often used when unchlorinated water would do. Rainwater barrels supply water that can be used for activities like gardening and outdoor cleaning.
As for compost bins, they recycle organic waste while considerably reducing the amount of organic matter sent to landfill. Furthermore, composting provides many benefits for gardening including enriching and rebalancing the soil.
To learn more about this project, see the press release.