Related by context. Frequent words. (Click for all words.) 79 basins 67 river basin 66 Basin 62 River basin 61 drainage basin 61 river basins 60 reservoirs 60 reservoir 60 Basins 56 estuary 56 tributary 56 River Basin 55 aquifer 55 headwaters 55 sediment 54 watersheds 54 rivers 54 tributaries 54 lake 54 groundwater recharge 54 lakes 53 catchment 53 groundwater 53 underground aquifer 53 water 52 watercourse 52 sediments 52 river 52 freshwater 52 aquifers 52 catchments 52 Reservoir 51 dam 51 wetland 51 Aquifer 51 waterway 50 hydrologic 50 hydrological 50 outfall 50 drainages 50 floodplain 49 wetlands 49 underground aquifers 49 River tributary 49 lakebed 49 sedimentation 49 creek 49 silt 49 riparian 49 freshwater lake 49 ponds 48 drainage 48 stormwater 47 watershed 47 dams 47 Reservoirs 47 dredged material 47 canal 47 impoundments 47 irrigated agriculture 47 riverbed 47 estuaries 47 weir 46 upstream 46 groundwater pumping 46 River 46 streambed 46 creeks 46 shoreline 46 lagoon 45 siltation 45 Sediment 45 waterways 45 subsurface 45 spawning habitat 45 Reclamation 45 inlet 45 Middle Fork 45 river valleys 45 lagoons 44 silting 44 landmass 44 flood plain 44 hydrology 44 spillway 44 dewatering 44 leachate 44 Groundwater 44 geological formations 44 salinity 44 gravels 44 Dam 44 canals 44 rainwater 44 tailings 44 Catchment 44 freshwater lakes 43 undrilled 43 cistern 43 Watershed 43 treated effluent