Recently I installed a Rainwater harvesting system on a 1200 sqft ranch home in surburban Allentown, Pennsylvania. You can likely duplicate this system in your home or business.
The collection system stores water in a basement, filters it, pressurizes it and distributes it to the toilets, garden hoses, and washing machine.
The system should save about 5000 gallons per year per person in your household (if you size the collection vessel(s) properly.)
It may sound a little tricky to install, but I have included pictures, a YouTube video, basic instructions, and a spreadsheet of all the parts/ tools you will need to take on this endeaver. You can do this with minimal plumbing knowledge!
1) Decreases your water bill by around 5000 gallons per person per year
2) Decreases load on the storm system in your neighborhood
3) Decreases the amount of water that will try to seep into your foundation
4) Decreases the amount of power consumed by your water utility, indirectly allowing them to keep costs lower for you.
5) Decrease costs associated with maintaining your water softener - as less water will need to be softened
6) Increase water softness so that clothes and vehicle wash more easily &you can use less laundry detergent / soap - thus polluting less
7) Eliminates sudden temperature/pressure changes in a shower when someone flushes a toilet, uses the washing machine, or a garden hose.
8) Increases anticipation of arriving storms - it's essentially raining free money for you to enjoy!
If you are feeling really ambitious and are able to collect the grey water from your bathroom sinks, showers, tubs, and laundry - this water can be recycled and filtered one more time in an auxillary system to supply water to the toilets and the garden hoses - though you will have to ensure that all of your soaps are bio friendly. Depending on your location, installing an inline UV sterilization filter may also allow you to use the water you collect for consumption.
Note: You should not collect the water from a kitchen sink, toilet, dishwasher as this becomes known as black water and must be sent into the sewer or septic system.