Keyline planning is a set of techniques and systems that organizes and manages water across both urban and rural landscapes. A Keyline Plan is designed to absorb and hold water within an area to improve biological diversity, increase soil water holding capacity, and enhance the hydrologic cycle. The plan can also be designed to store surplus water in practical locations to recharge groundwater, provide passive irrigation, create wetland mitigation banks, and provide flood hazard mitigation value. The plan may include systematically placed features of a development, such as roads, buildings, subdivisions, and utilities.
One primary objective of keyline planning is to quickly develop deep soil fertility within a developed landscape. Soil developed in this manner will create a biological soil structure that increases the soil water holding capacity, which is then capable of capturing and using stormwater runoff as a resource. Keyline management techniques quickly improve both the structural stability and the biological fertility of soils to levels that are likely better than existing conditions,which then helps to mitigate soil erosion, dust storms and flood hazards.