Related by context. Frequent words. (Click for all words.) 52 dam 51 streambed 51 canal 51 Friant Dam 50 dams 50 irrigation canal 49 underground aquifer 49 tributary 49 irrigation ditches 49 watercourse 49 aqueduct 48 flume 47 creek 47 river 47 groundwater 47 canals 47 Taum Sauk 47 waterway 46 riverbed 46 rivers 46 tributaries 46 earthen dam 46 Creek tributary 46 roadbed 46 sewer pipes 46 sediment 46 sewage 46 reservoir 46 waterways 45 kilovolt transmission line 45 drainage canal 45 spillway 45 silt 45 groundwater pumping 45 irrigation ditch 45 streambeds 45 outfall 45 levee 45 riverbeds 45 sewer mains 44 irrigation canals 44 aqueducts 44 aquifers 44 sedimentation 44 hydropower dams 44 headwaters 44 drainage ditches 44 dike 44 Salton Sea 44 underground aquifers 44 hydroelectric dams 44 Indus river 43 silted 43 Cowlitz River 43 Truckee River 43 culverts 43 fish hatchery 43 seepage 43 septic tanks 43 river basin 43 storm sewers 43 raw sewage 43 culvert 43 drainage ditch 42 aquifer 42 Kosi river 42 Sheyenne River 42 Hetch Hetchy 42 Tuolumne River 42 Amur River 42 Nisqually River 42 snowmelt 42 drainage pipe 42 Songhua 42 snow melt 42 roadway 42 Elwha River 42 levees 42 hydroelectric plants 42 lagoons 42 drainage pipes 42 reservoirs 42 Raw sewage 42 outfalls 42 wetlands 42 Karakoram Highway 42 beaver dam 41 water mains 41 floodway 41 septic systems 41 sluice gate 41 spawning habitat 41 hydrologic 41 meltwater 41 estuary 41 Ogallala Aquifer 41 impoundments 41 spillways 41 River tributary 41 mountain snowpack 41 creek bed