Reading this week:
- Education of a Wandering Man by Louis L’Amour
- For Your Eyes Only by Ian Fleming
- The Man with the Golden Gun by Ian Fleming
- Thunderball by Ian Fleming
- On Her Majesty’s Secret Service by Ian Fleming
This week I finally got to stake a pond. As I said before, I am a rural aquaculture promotion specialist, and that means I teach fish farming. To farm fish, you need a fish farm, and step one of that is pond staking.
Technically, I am still in community entry, and therefore not yet responsible to get down to any serious business of teaching fish farming. The main goal of this period is to adapt to living in the village and learn about the community so I can most effectively help them with their needs. However, I am a mission-oriented dude, and I am here to teach people how to farm fish, so I wanted to get down to business. This post is about to get technical, but I thrive on the technical.
The Rural Aquaculture Promotion program focuses on bringing aquaculture to rural farmers, and so that means a focus on using locally available and preferably free materials. Therefore, the fish farming we do is largely performed in earthen ponds, dug out of the ground. Pond staking is the process of measuring out where to dig the pond and build the walls. The tools required for this are wooden stakes, string, a line level, and a mesuring tape.
To stake a pond, you start with a field. Ideally, you want a slope between 1-6%. Since this is rural Zambia, you take what you can get. You start at the highest corner and put in a stake. From here, perpendicular to the slope, you measure out the top wall. The top wall will be, again ideally, 24 meters. The “standard” sized pond in the program and the Department of Fisheries is 20mx15m, and a 24 meter outside dimension, once wall thickness and freeboard is taken into account, provides a 20m waterline.
Once you’ve established the top wall, you measure out a right triangle with 3m and 4m legs and a 5m hypoteneuse. This will ensure the pond is square. Once you’ve put these stakes into the ground, you use them as a reference to measure the side wall. The outside dimension of the side wall is 19m (ideally, etc etc). Now that you’ve got two walls measured out, you complete the square. The outside walls have been measured.
The top of the dike wall should be 1m wide. So you measure one meter inside from all of your outside walls, and stake the four corners. Finally, you measure the pond bottom box. The inside walls of the pond are sloped in order to provide fish an ideal nesting location and to allow for easy access into and out of the pond, and the pond bottom box takes these slopes into account and shows where the flat, bottom part of the pond will be. From the top of the inside wall, you measure 3.3 meters from each wall and place a take. From the bottom of the wall, you measure 3.9 meters and place the remaining two stakes. This should form a trapezoid.
Next, you run a string around all the stakes you just staked, and make sure the string is level. This shows where the top of the dike wall will be, and provides a guide for digging the rest of the pond. From there, there are a few small details like staking out lines showing the slopes, and the cut/fill line, but that is a quick overview of the pond staking process. Since it is the vital first step of digging a quality pond, we went over it a lot in training and I was excited to put my knowledge to use. Next week’s post will be more interesting. Promise.