How do I pump my bath water to my garden for watering?

Question

After my kids have a bath, I want to be able to pump the water out into the garden. They usually just have a bath in water without soap etc. so it's still relatively clean.

Usually I just try to siphon the water out with a hose but this doesn't work very well as the bath level is very close to the level of the garden. The hose also has to go up and out the bathroom window which makes starting the siphon difficult.

Does anyone have any suggestions on what might be a good way to achieve getting the water out of the bath into the garden without spending heaps on a water pump?

EDIT I haven't spent any more time on this yet however my thoughts are to see if I can salvage a water pump from on old washing machine and wire it up to pump the water out...thanks for your suggestions.

Answer 1

Water pumps aren't very expensive if you know where to look -- the submersible pumps for water fountains or hydroponics are often under $20. You may need an adaptor to attach it to a garden hose, or just buy a length of tubing for the pump if you're not going too far with it.

The only issue is that they won't drain 100% of the water. They typically have feet to raise them a little bit off the bottom of their tank, and won't drain 100% of the water.

It's not as versatile as a wet/dry vaccuum, but they're so small you can more easily keep it in the bathroom.

You generally pay more for larger pumps ... they're rated by GPH (gallons per hour), generally the low end (sub $10) ones are under 100GPH (~1.5 gallons per minute) and you can often get 200-300GPH for $20-$30. You just have to decide how fast you want the tub to drain ... but I'd also look to make sure the pump had an appropriately sized outlet to try to couple a garden hose to.

You can also check hardware & automotive stores for 'siphon pumps'. They're inexpensive (about $15), but they're often either hand-powered or battery powered though, as they're frequently used for draining gas cans or automotive fuel tanks ... but they will drain to the bottom, or at least further than most submersible pumps.

Answer 2

Perhaps you could enlist the help of your kids - fill up some water guns and let them loose on the garden!

Answer 3

A relatively low cost (~$100), and multipurpose solution is to purchase a Shop Vac style vacuum with a water pump feature. I have one that I use when my basement floods.

Basically it's a standard canister vac that has a water pump attachment that goes on instead of an air filter and bag. Then you attach a garden hose to a port in the lid and run the hose to your garden. Turn your vac on then put the nozzle right into the tub (careful of toys :)). These are relatively limited capacity, so you may have to let it drain, but if you suck relatively slowly, you shouldn't have a problem.

I bought mine from a big box hardware store, but you can find them on amazon. They aren't cheap, but they are multipurpose.

Answer 4

If you don't mind doing the siphon thing, you can easily get the siphon action going by putting a valve on one end of a hose and submerging the hose into the tub water to purge the air from the hose. Then close the valve (to keep the water in the hose) and put the valve end out the window to a bucket/container outside. Once it is in position (non-valve end is in the water in the tub and valve end is lower outside), opening the valve will start the siphoning going. I imagine you probably already know how that all works but the point I wanted to make is that filling the hose up ahead of time and shutting the valve keeps the water in the hose and makes siphoning the tub a breeze.

I've got a small submersible pump - the kind one might use for hydroponics - that will move maybe 120 gallons per hour. It's not terrible fast but it works quite well. Might have paid $25 for it. My pump will attach to a standard hose. If you didn't want to put a pump like this directly in the tub, you could put it in a 5 gallon bucket and then fill up the bucket in the tub.

I've seen folks use a gray water setup where the tub water drains not down to the septic field or sewer but rather outside to be used in the garden. Probably not easily retrofitted into old construction but the idea is neat.

Answer 5

The most difficult but best option for this is to re-plumb the drains to a separate tank. You could then pump this to the garden at will. This is called water recycling or greywater use. FWIW, I had spoken to the county health dept about this last week and they don't recommend it as any pathogens could be washed off the person and then onto the garden. You may be able to get away with subsurface watering as there would be no splash onto any plants.

But hey who cares pig/cow farmers do it in the fields....