A lock is a wooden trough that is designed to transport water from one area to another by letting gravity do the work. Natural springs or underground streams are excellent sources of water that can often be diverted to a pond area or create a source of running water in your garden. If your lift slopes work to allow you to cast your gate downhill, the water can be moved for free without the aid of pumps for years and years at no cost.
I was fortunate to have an underground water table that is so high in the ground that my basement has a year-round creek that runs along the base of a wall in a concrete channel. This channel exits the basement through a four-inch tube in daylight about eighty feet or so from the building. At the point where the pipe meets daylight, the pipe itself is approximately four feet above the ground on a stone retaining wall. The area slopes downward and outward from that point and generally ends about ten feet below where the ground flattens out. The lower property has a small stream that winds its way down to our eight-acre lake. The creek is year-round except for the driest summers. I’ve seen the creek dry out only once in thirty-five years and that was only for a few weeks or so. Over the years, I have designed lawn areas from the house to the lake (approximately 750 feet) that provide beautiful areas for walking. Some benches here and there, some shaped yews and potted deer resistant plants and for me it is heaven in the summer to sit quietly and listen to the summer winds. My children and grandchildren have played here for years and now they have started adding their own keys to the property. One day while sitting I stared at the pipe that came from the basement of the house and thought it was a great way to create a free waterfall or small pond if only I could get the water in there. The idea for a hatch quickly became a reality after a short discussion with the wife and we went to look for building materials.
I decided to use pressure-treated wood for the lock as it would last for many years and after a few years of running water through it it shouldn’t be harmful to plants or fish. I chose boards six inches wide by sixteen feet long, as they were the longest the lumberyard had. I installed my sawhorses and began to build my lock. I built the base using two boards side by side, which made it a foot wide. Adding a few short thirty-centimeter-long pieces to the side as suspenders provided additional strength to keep it from falling off. The sides were then made from a board, each making the finished channel a foot wide and six inches deep. I used good galvanized screws for mounting as they will not back off over time and a drop of good silicone caulk on each joint would provide a good temporary seal between the boards.
Over time, as the sealant aged and failed, dirt, leaves, and other debris would seal the joints from the inside, making the airlock virtually impervious against leaks. Starting at the point where the water was coming out of the basement drain pipe, I placed the first gate with one end to capture the water and the other pointing towards where I wanted to create a small pond and garden area. I later found out that I had to add a baffle board at the water entry point to funnel the water into the lock when the water flows were high enough to shoot past the lock rather than just falling into the lock . I built a total of three sixteen foot long lock chutes and zigzagging them down the hillside moved the water nearly forty feet horizontally from where it started. It requires very little slope for the water to run. I was lucky enough to have a six foot tall rock that by placing the last gate on top of the rock and letting it hang in the air several feet created a six foot tall waterfall that falls on a small fish. pond I built underneath. I place goldfish in this little pond every summer for the children to feed and watch. The water constantly falling from the lock keeps the water well aerated and fresh throughout the summer. My gate has been in place for about twenty years and except for an occasional removal of excess blades and slight realignments, it has performed well without further maintenance.