Before you build a dock for a pond,determine the bottom conditions of the pond. A floating dock is recommended if the soil is very loose. A dock with support posts is suited for soil which is firm and sandy or rocky. Design a plan, either by using existing designs or create your own. Choose the building materials you want to use for the dock construction. According to the Environmental Protection Agency, lumber treated with chromated copper arsenate is suited for dock construction because it withstands moisture. This project requires the help of at least two people.
Drive support posts into the pond bottom. The support posts should be no further than 8 feet apart. The number of posts depends on the desired length of the dock.Place the posts parallel to each other. A ladder can be used if you're working in shallow water. Premade posts which slide into brackets and are available at home improvement centers are an option if you plan to disassemble the dock during the winter season. For a stationary structure, use 4-by-4 posts of pressure treated lumber, ideally treated with chromated copper arsenate for added moisture protection.The height of the post is determined by the desired distance of the dock from the surface of the pond. Drive the posts into the soil using a mallet and to a depth of one foot or more to insure stability.
If posts can't be driven because the ground is too hard or rocky, or because the pond is lined, consider building a floating dock by attaching Styrofoam between the dock's floorboards and its frame.
Construct a frame using 2-by-6 boards of treated lumber. Using a circular saw, cut three boards to the length of the dock design plan. Cut two boards to the width of the design plan.Space the three length boards evenly apart and attach a width board at each end. Butt joints (a width side to length side connection formed at right angles) should be secured with stainless steel lag bolts for added stability. Attach the center length board to the width boards with stainless steel screws. Attach the frame to the posts using stainless steel screws.
Attach 1-3/4 inch decking to the frame. Leave a 1/4-inch space between each decking board. This allows rainwater to drain through the decking. .
Adding bumpers, such as tires, to the outer edge of the dock or attaching a hand rail are individual design choices. Attach stainless steel L brackets to the frame. Tires can be hung off of the brackets to form bumpers.