Watering Systems

This year (2012) has been hot across much of the USA, and much less precipitation in our area than normal. Where we have in the past been able to rely on our 3200 gal roof catchment cistern, it has been of no help this year. In the past month we have had around .25 inch of rain, which just enough to send a brief trickle into the cistern. We have had to use well water to keep the garden going this summer.

Last year we used 3/4 inch PVC pipe with regularly spaced small holes drilled, per the Mittleiter method. Our garden land has a slope to the row, and we found that we did not have enough water pressure to pressurize the PVC system, so the water just ran downhill, watering the lower end of the row too much, and no water at all at the top end of the row. This turned out to be a complete failure of time, material and effort.

This year, we have installed the commercially common T-Tape drip system, and we love it! The T-Tape system comes to pressure before the water is released from the in-line emitters, and we are finding consistent watering along a drip line with descending slope down the row. The system is simpler to construct and deploy than our PVC pipe system of yester year. These components are used by commercial farmers across the USA, and the system works well.

The watering is done with drip rather than a spray, so less water is lost through evaporation in the air. Some farmers may bury the drip lines and water under the soil.


Components:

Our feed line is a garden hose. There is slip connectors that join the main line tubing with the hose connection.  From the main line, you punch a small hole, and insert a T-Tape fitting that allows you to connect the T-Tape to the main line. At the end of the main line, you insert a plug. At the ends of the T-Tape lines, we tie the tape into a knot.

Our main hose to the garden has a flow rate of 5.5 gallons per minute. With this flow, we are able to pressurize and water up to 15 runs of T-Tape at a length of 90' each. This equals a row run of 1,350 feet. When we turn a zone on, it will take a few minutes to fill the main line and tape with water, and then build to pressure. All lines start to drip at the same time when there is pressure in the zone.

The links below go to the online store were we purchased our components.

Main line. We use 3/4 inch mainline
T-Tape: 8 mil, 8 inch on center
Fittings:
     3/4 inch connectors, including hose connectors
     3/4 inch barbed plugs
     Main line to T-Tape fittings
Tools: Punch for a .400 barb
Hold downs

We are experimenting with a few additional components: an in-line particulate filter, a fertilizer injector and tree drip line circles.


Resources:

• Dripworks (web store)
• Drip Depot (web store)