Imperial units commonly used units for length are (li), (tseung/cheung), (tsek/chek), (tsun/chun), (fen/fan) in descending scale order. These units are now rarely used in daily life, the imperial and metric systems being preferred. The imperial equivalents are written with the same basic Chinese characters as the Chinese system. In order to distinguish between the units of the two systems, the units can be prefixed with "Ying" () for the Imperial system and "Wa" () for the Chinese system. In writing, derived characters are often used, with an additional (mouth) radical to the left of the original Chinese character, for writing imperial units.
Imperial Reservoir attempt to enter the Imperial Reservoir from western Arizona, south of the Bill Williams River: the Bouse and Tyson Washes. Both washes end on the eastern perimeter of the Colorado River Indian Reservation along the Colorado River. Neither enters the river proper, except in extreme flood stage. No "lengthy" watersheds flow eastwards from California; all are short distance, in the extreme aridity of this desert region. Imperial Reservoir The Imperial Reservoir is an artificial lake formed by the construction of the Imperial Diversion Dam across the Colorado River in the Lower Colorado River Valley of Imperial County, California, and Yuma