m, meter, metre

weir, spillway, reservoir, dike, forebay, river, levee, reservior, tributary, headrace, fishway, canal, lake, river basin, cofferdam, flume, watercourse, culvert, hydropower, sluiceway, tailrace, embankments, headwaters, flowage, streambed, murrumbidgee river, basin, brahmaputra river, creek, millrace, outfall, silt, riverbed, bighorn river, bailey bridge, water, aqueduct, floodplain, waterway, penstock, trestle bridge, oxbow, dredging, sluices, headwater, bridge, zambezi river, anicut, coulee, sedimentation, salween, downstream, retaining wall, flood plain, wetland, hydro, ponds, riverbank, groundwater, millpond, irrigation, freshet, tsangpo, flood, pumping station, hydrological, estuary, aquifer, breakwater, catchment, hatchery, merowe, hydroelectricity, indus river, lagoon, distributary, quarry, floodgate, impoundment, septic tank, sewage, drainage, revetment, truss bridge, groyne, namoi river, overtopping, floodwater, parana river, waterline, berm, lockmaster, cusec, brook, roadbed, cabora bassa, watershed, drainage basin, landslip, sediment, waterfall, seawall, dams, pier, causeway, embankment, stadium, trestle, billboard, glacier, viaduct, dock, building, raft, asteroid, dune, reform, block, curriculum, democracy, pioneering, pyramid, completed, control, coordinated, democratizing, design, erection, filibustering, fill, hydroelectric

aswan dam, aswan high dam, floodgate, high dam, hoover dam, milldam, water gate, weir

assouan, assuan, aswan, backwater, break, burst, buster, dam up, disfigurement, fish ladder, flashboard, flashboarding, hoover dam, ijsselmeer, lake mead, milldam, spill, spillway, wasteweir, weir, zuider zee

hectometer, hectometre, hm

barrier, block, close up, female, impede, jam, metric linear unit, obstruct, occlude

dam up, decameter, decametre, dekameter, dekametre, dike, dkm, levee