Rainwater Harvesting and using Gray Water

As environmental and financial restraints becoming increasingly onerous, the efficient use of natural resources becomes more and more important.
Rainwater/Gray water harvesting and storage is a much more efficient way of providing water for your garden.

The main issue is usually collection and storage of the water. Water can be collected from existing downpipes from either the house or any garages and outhouses you may have. Whether the water is collected from your roof or from a bath/shower (a more reliable source) it will have to have the leaves, grit, soap, etc taken out to ensure there are no blockages.
The operation of the rain water/grey water harvesting system is completely automatic and will normally require only the same bi-annual maintenance visits as other Auto-Rain systems.

Assuming the tank(s) can be installed without major works in a garage or other outbuilding, the rain/gray water harvesting installation will add about £1000 to the cost of a new irrgation system for a large garden, since it includes a tank and pumps that will be required for the lawn pop-ups. The cost will obviously be far less for a balcony or patio !

Many commercial operations such as car washes, farms, etc have found that their investment in a rainwater harvesting system has paid back 100% in less than three years, purely due to costs saved by reduced water use !

Rainwater Harvesting tanks in a garage

Beating a hosepipe ban

The easiest and most reliable source of waste water is from a bath or shower.
Water from sinks and household appliances contains too many additives to be used without extensive and expensive treatment.
Bath/Shower water can be used directly without treatment, but may become smelly when stored, and will soon block up the the small jets used in irrigation systems.
Fortunately a new filter has been specifically developed to remove soap products fom the water.
A diverter valve is plumbed into the existing bath waste pipe and this automatically sends water to a small (200 litre) collection tank fitted with the special filter, a small mains powered pump and a timer. The filter removes all the soap so that the water can be stored for a day or more.
In the winter, the grey water will run into it's usual gulley.
This would normally allow you to water a single area of your
garden from a single bath. The more baths you take, the more water is available to irrigate your garden !

Phone: 020 8704 1193             Mail: cb@thebotanicalgardener.co.uk