located in the Yorkshire Dales National Park Gaping Gill - "highest" unbroken waterfall in England, with water falling 110 m from the surface into an underground
stopped almost all water flow over Niagara Falls on March 29, 1848. Fischer، Nancy (23 يناير 2016). "Niagara Falls is going to go dry – again". بوفالو نيوز
cams turned by a novel two-stage chain drive system that teams with a semi-dry-sump lubrication technique and plated aluminum cylinder bores to keep the
ICPRB. District of Columbia Water and Sewer Authority. "STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1930 - 2018, BY WATER YEAR, near WDC". USGS. 2019