I’ve noticed that the soaker hose that runs along the west side of my concrete slab foundation is out of pressure before it reaches the end.
The trip from the faucet to the tip of the hose is about 70 feet. I’m turning the faucet on hard enough that the first 20 feet of soaker hose is not just dripping, but spraying.
Yet the water still doesn’t make it to the end of the hose. A 70 foot run is too much.
The purpose of foundation watering is to keep the water content of the soil under your foundation as uniform as possible. Since you can’t keep out the rain, the thing to do is keep the soils reasonably damp during dry periods.
To be successful, a watering program must keep the soil damp down to a depth of 4 or 5 feet. The more trees and large shrubs that you have, the harder this is to do. Big plants take a lot of water out of the soil.
The way around this problem is to use a combination of regular garden hoses and soaker hoses. To provide even watering and to offset the pressure drops that occur in soaker hoses, a separate water line (or hose) is run to each section of soaker hose.
The soaker hoses will extend no more than 20 feet away from the connections to the water lines.
A typical home will have about 4 zones, each with its own water line and control valve. For a few hundred dollars in hoses and valves (and some hard work), homeowners can build their own systems. Here is a simple diagram.
There is no simple way to determine how much and how often to water. You must use your judgement. The hotter and drier it is, the more you need to water.
How wet the surface is, is not a good indicator of how your watering program is working. It is possible for the surface to be soaked while the soil a foot deep is relatively dry. One way to check, if you have clay soils, is to use a plumber’s probe.
A Plumber’s probe is a 4 or 5 foot long fiberglass pole with a “T” handle on the end. If your soils are too wet, then the pole can be pushed down into the soil with little or no effort.
When the soils are wet, but not too wet, you should be able to push the probe 3 to 4 feet by leaning heavily in the handle. If you can’t push the probe into the ground without banging on it, the soils are probably too dry.
This test will not work well in sandy or rocky soils. Do not use a metal pole to probe the soils. If you hit a buried electrical line with a metal pole, you could be electrocuted. If watering does not work, you may need foundation repair.
technorati tags:soaker, hoses, clay, soil, concrete, slab, foundation