Municipal Water and Booster Pumps

Hey everybody!

So I'm wondering if anyone has any experience with using municipal water for a sizable market garden ( I have over an acre and some rows that are 100 feet). We have a decent riser that has I believe a 2" pipe going to it but the blocks are all spread out and just have garden hoses going from the riser to individual blocks. It takes several hours to get a good soaking with this system and most of the blocks just be split into sections of 8-12 rows as well.

This is my first year on the plot and I'm realizing the water cost has been prohibitive. I've come across a few potential options such as using a booster pump (or two or...) or running hundreds of feet of poly tubing to each block to maybe create a bit less friction loss. Has anyone had any experience with this? What did you do? How about anyone ever use a chlorine filter... What kind?

Thinking of maybe switching this plot over to mainly growing perennial herbs anyway but would be nice to fix some of this either way. Thanks in advance for your help and happy growing!

Hi Oliver! Help me out -- I'm a little unclear on what you're asking.

I assume your water is metered, so increasing the pressure with a booster pump will speed up the watering but it won't reduce your bills.

Gardeners here don't seem to worry too much about chlorine. It doesn't seem to hurt plants, though I don't know about effects on the living soil biota. When I truck in a cube (1000 litres) of municipal water it gets well aerated/mixed and sits in open tanks or barrels for a day before I use it. There is little smell of chlorine the next day. No problems noted so far.

With the low pressure I am having to run the water for up to 3 hours since it goes downwards so much instead of soaking out sideways. With proper pressure I should be able to water for only, say 30 minutes, maybe an hour...as far as I understand.

Oliver Aurand wrote:I've come across a few potential options such as using a booster pump (or two or...) or running hundreds of feet of poly tubing to each block to maybe create a bit less friction loss.!

It's true that narrow pipes (like a garden hose) have a lot of internal friction that restricts flow. If you can create central hubs that are fed with large diameter pipe, you will typically have better flow.

Are you using drip tape? I am going to guess so since you are talking about length of the beds and the water just going down.

The water going down is more dependent on the SOIL type and consistency then the pressure of the water. If the soil is porous (say sand) the water will not pool and will not spread out.  

As to the volume of water and how much area that waters it will remain constant. If you are trying to get 1 inch of water on your beds it will take the same amount of water if it all comes over 30 minutes or if it happens over 3 hours. There are benefits to doing it over 3 hours because the water will seep in better and really soak the ground. Where as if you do it quickly the water may run over the surface rather than seeping into the soil.

I would look at the issues you shared more from the side of "What are you trying to achieve" are you trying to be efficient in time to water or are you trying to be efficient in amount of water used? If you want to be efficient in time then overhead sprinklers may work better but if you are trying to be efficient in amount of water then drip is best (not most drip that I have seen needs to be at under 25 psi to work correctly - so that gives you a limit on water pressure you can use).

Unfortunately the description of your problems do not provide enough information for people to help you.

In my area, the water department has special, cheaper rates for water for agricultural use. We have to prove we have a farm business, and we have to have a backflow prevention system which must be certified once a year by a plumber. As long as we do the paperwork we get a very good rate on water. Not every area has this, but it might be worth contacting your water department about.

Chlorine can kill beneficial bacteria in your soil. I prefer to build up good bacteria as much as I can. One way to get rid of the chlorine is to build some tanks to hold water before it goes to the farm. The tanks need to have a way to let the chlorine off gas, such as being open to the air. (However, you don't want a bunch of branches or junk getting in there, there are many ways it could air out.) Tanks could also increase your water pressure and give you a small buffer from any shortages.

If it's allowed in your area, you could later attach water catchment to the tanks.

If you have some slope on your property, you have some better options to irrigate without so much expensive piping.