A few weeks ago, we posted an instagram of Shane with a set of divining rods. He was skeptical about their utility at first, but he swears he felt them move on their own in his hands – a “sure” sign of water below. This week, #TeamTomatoJos continued our search for water to feed our thirsty tomato plants once we transplant them into the fields.
We have over 30,000 tomato plants ready to move from the greenhouse to the open field, and each plant will need over 100 gallons of water in order to mature and bear fruit. That’s a lot of water! We blogged about irrigation practices back in August, but with less than a week to go before transplanting, we wanted to update our readers about our specific plans for irrigation infrastructure. We’ll be using drip lines for the nucleus farm, but since we’re not next to a river or any surface water sources, we will need to bring water up from a well, or a borehole.
The borehole
Water Dowsing (also called Water Witching or Divining) is an ancient technique that is still used today in many parts of world to locate everything from gemstones, to buried pipes, to water. The technique itself is straightforward, if a little hokey: the diviner holds one or two rods, sticks, or other devices – called dowsing rods or dowsing sticks – and walks around until the rods “move” on their own. It’s kind of like an Ouija board. This week, the borehole engineer came with dowsing rods made of brass.
The practice of dowsing has never been scientifically proven to work, but #TeamTomatoJos tried holding the rods and they definitely moved more than a couple of times! Our borehole engineer also utilised the Vertical Electrical Sounding technique to determine the electrical connectivity of the subsurface materials. By measuring this connectivity, a 100-meter deep map of the subsurface was created. The engineer explained that this map enables him to select the right location for the borehole: a place where a sufficiently large body of water is present. Now we just have to wait and see if there is actually any water there when we start drilling!
Water storage
Tomato plants only need water when they undergo photosynthesis – this means that they don’t need water at night, but they need a LOT of water during the day. We plan to pump water 24/7: during the day, it will go directly into the fields, and at night it will be stored in large plastic tanks. Each of our one-acre fields is equipped with two 5,000-litre storage tanks. When the plants fruit in a few months’ time, they will need 20,000 litres of water per acre per day so that the tomatoes can grow big and juicy – our water storage system will be absolutely crucial at that stage!
We expect our borehole engineer to begin construction on Tuesday – follow us on instagram and twitter to keep track of our progress!