Trenching involves making a system for collection, supply, or drainage of water, whether stormwater or waste water. When planning and constructing trenches, it’s very important to figure out how water will be supplied to a house and how it will drain into a septic tank or public sewer, and eventually end up in a water purification system. Pipes laid into trenches are usually 20 cm in diameter, while horizontal fittings slope at about 2%. You can connect to a public sewer only if you’ve obtained an approval based on the planning permission. Check out other advice we’ve prepared, and use our calculator to check the cost of this work. You can also always contact our experts, who’ll be more than happy to reply.