Connecting Water Butts

Find out how to connect two or more water butts to multiply available water storage capacity

A water butt (1) is a vital component of any small to medium size rainwater (2) or greywater (3) harvesting system. While larger systems utilise 1,000+ litre underground water storage tanks and require professional installation, a water butt can be set up by anyone very easily in conjunction with a suitable rainwater diverter (4) or greywater diverter (5).

Empty water butts of around 200 litres capacity can easily be handled by one person, they are very affordable, and they are very easy to find (new, used, and recycled), but 200 litres is the equivalent of just three average UK baths. To increase this water storage capacity while retaining the ease and flexibility of using a relatively small and lightweight storage vessel, multiple water butts can be connected together in a chain.

Connecting Water Butts Together

Two water butts connected together to double water storage capacity

Typically the connection between two water butts is made between the high water marks of each butt as pictured above. This is because the bottom of each water butt is likely to accumulate debris (leaves etc) over time which would block the connecting tube if it were connecting the bases of the water butts.

Note that a tap is needed for each water butt in the chain.

Connected in this manner (as illustrated above), when the first water butt (Butt 1) in the chain is full, water will start to flow into the second water butt (Butt 2). It is essential that the water outlet from Butt 1 is below the height of the rainwater/greywater input (arriving from the diverter), and that it is also a couple of centimeters above the water input hole of Butt 2.

Further water butts can be added to the chain in exactly the same way. Five 200 litre water butts connected in this way would give around 1,000 litres of water storage capacity for far less than the cost of one 1,000 litre water storage tank.

The majority of any debris washed down from the roof will accumulate in Butt 1 and so the water in Butt 2 will be cleaner and more suitable for use in a porous pipe (6) irrigation system. A filter placed between Butt 1 and Butt 2 will clean up the water without any increased risk of a water butt overflowing. (If the filter does get blocked then any overflow from Butt 1 will be automatically diverted down the drain. However, if a filter between the downpipe and Butt 1 got blocked, either Butt 1 or the guttering could overflow.)

The Physical Connection Between Water Butts

The connection between the water butts can be made very cheaply with a length of old hosepipe which is then glued and silicon sealed into place. However, this is not very reliable and could start to leak. A better alternative is to purchase a dedicated Water Butt Connection Kit such as the one pictured below.

These water butt connection kits include a 1-2 metre length of very flexible hose, and all the fixtures and fittings necessary to make a secure watertight connection to each water butt - plastic bolts and rubber washers.

These kits cost from Ł10-15, but you could probably put one together for a bit less purchasing the individual parts from a local plumbing trade shop.

Another alternative is to purchase a couple of water butt hosepipe connectors such as those pictured below from Hozelock for under Ł10, fit them to the water butts, and then connect them via a length of standard hosepipe.

Water butt fittings - connect a hosepipe to a water butt

Web Link References

(1) http://www.reuk.co.uk/Water-Butts.htm
(2) http://www.reuk.co.uk/Collect-Rainwater.htm
(3) http://www.reuk.co.uk/Greywater.htm
(4) http://www.reuk.co.uk/Rainwater-Diverter.htm
(5) http://www.reuk.co.uk/Greywater-Diverter-Valve.htm
(6) http://www.reuk.co.uk/www.self-sufficient.co.uk/Porous-Pipe-Plot-Irrigation.htm

Article from REUK.co.uk:
http://www.reuk.co.uk/Connecting-Water-Butts.htm
Published: 1st June 2007
Š REUK 2009