Complex sentence: Butter Brook reservoir was constructed in 1915 and opened in 1916 to supply water for Ivybridge however by 1994 it was only supplying 20 households with water but in 1994 it closed down.
Split into simpler sentences: Butter Brook Reservoir was constructed in 1915 to supply water for Ivybridge and opened in 1916. However, by 1994 it was supplying only 20 households with water and it closed down.