Novel tools and techniques might provide for designing and/or implementing a drainage system for an agricultural area, based at least in part on three-dimensional soil modeling. In some embodiments, a computer system might identify one or more elevation points at each of a plurality of locations within the agricultural area, based on 3-D topographical surveys and 3-D soil profiles. A location of one or more outlet points within the agricultural area, where water will drain out, may be identified. The computer system might also determine location, length, and/or cross-sectional size for each of one or more drainage pipes (including main, sub-main, and lateral drainage pipes), based at least in part on optimization of location and/or costs based at least in part on the 3-D topographical surveys, the 3-D soil profiles, the one or more elevation points, and/or the location of the one or more outlet points.