Resources
Find the resources you need to understand the 3D Hydrography Program.
HydroAdd3D
Hydrographic addressing is a powerful way to link observations – flow measurements, water-quality measurements, water intakes and outfalls for example – to the broader hydrographic network. HydroAdd3D makes hydrographic addressing to the 3DHP network available to users without additional software or licensing.
Mainstems
Mainstem rivers are the backbone of a connected network of hydrologic units that cover the landscape. A mainstem connects a headwater source area to an outlet. This data release identifies the same mainstem paths in hydrographic datasets for the conterminous US.
Flow Network Derivatives
The flow network in 3DHP data is what gives it its analytic power. Flow Network Derivatives (FNDs) boost this power by pre-calculating several network characteristics to make network analysis faster and easier.