Friday, July 6, 2012

Cool Technology of the Week

Continuing my series of farm related cool technologies, today's post is about solving a practical agricultural problem.   How do you keep water flowing in the barn during the freezing temperatures of winter?

Of course, you could use electrically powered pipe heating tape but what if the power fails on a cold winter night?

For over a hundred years, farms have solved this problem by using a freeze-less yard hydrant such as the Woodford Model W34

The idea is simple.

In Massachusetts the frost line is between 30-35 inches.  

At our farm, all water pipes are buried 4 feet or greater, ensuring they never freeze.

A yard hydrant connects to water sources below frost line.   When the handle is opened, a 4 foot rod moves a gasket so that water can flow up the hydrant.   When the handle is closed, a siphon below the frost line is opened, draining the hydrant.    Thus, there is never standing water in the hydrant that can freeze.

Our hydrant has 27 inches above ground and 48 inches below ground.   We also created a dry well around the hydrant and siphon to prevent any runoff from accumulating around the pipe.

A simple technology that uses the insulating properties of the ground instead of electricity to keep water flowing in the winter.   That's cool!

By the way, a weather station on our barn provides detailed data for Sherborn, Massachusetts to most popular internet weather sites and the National Oceanic and Atmospheric Administration.    This winter I'll be able to track the temperatures and ensure our animals and infrastructure are protected from the cold.

2 comments:

Andrew said...

John - a couple words of warning on these hydrants. In NC our frost line is about 3-4 inches! but we still use these hydrants on our horse farm - buried about 2 1/2 feet. However, over time the bleeder nipple at the base has a tendency to take in enough debris to interfere with the seal. So I always wrap the valve with a piece of stocking before burying and try really hard to use clean gravel around the base....although I have done it many times, digging up a leaky frost free hydrant is not my idea of fun - I would rather spend that time working on sustainability for heath transformation!

Tomcat said...

Dr. Halamka,

Then there is this home made, passive, zero energy ice box/refrigerator by a fellow in Massachusetts:

http://fourmileisland.com/IceBox.htm