National eDirectives System: provides detailed Engineering Tools & Documents under various Directives including Handbooks: National Engineering Handbook, National Agricultural Land Evaluation & Site Assessment Handbook (under Land Use), National Water Quality Handbook and National Handbook of Conservation Practices (under Technology); Manuals: National Engineering Manual, Emergency Watershed Protection Manual and Watershed Program Manual (under Project Development & Maintenance); and Engineering Technical Notes, Technical Releases, and User Guides (includes tools and computer models / software)