O'Shannassy Reservoir

O'Shannassy Reservoir supplies water to Silvan Reservoir, which distributes it to most parts of Melbourne. The dam was completed in 1928 and is an earthfill embankment with reinforced concrete core wall.

O'Shannassy photograph

Rainfall figures for O'Shannassy Reservoir

Storage and rainfall data

Use our interactive web application to view current storage levels and catchment rainfall for O'Shannassy Reservoir:

Key rainfall facts (mm)

 

​Month Wettest​ Driest​ Average​
​January 174.2 (1956) 1.8 (1990) 64.7
February​ 246.4 (1939) 0.4 (1991) 62.3
March​ 189.0 (1970) 3.6 (1951) 71.9
April​ 295.7 (1935) 13.2 (1963) 101.6
May​ 364.2 (1960) 3.0 (1934) 124.1
June​ 438.4 (1952) 23.0 (2006) 135.2
July​ 310.4 (1964) 45.0 (1994) 148.5
August​ 433.1 (1939) 49.8 (1982) 168.8
September​ 280.8 (1992) 34.0 (1961) 148.9
October​ 315.5 (1934) 22.4  (2015) 133.9
November​ 252.5 (1952) 25.9 (1927) 110.5
December​ 231.6 (1930) 9.4 (1972) 97.1
Total rainfall​ 2166.9 (1952) 829.4 (2006) 1367.5

Historical rainfall data (1927-2019)

graph showing O'Shannassy Reservoir rainfall data

Location of O'Shannassy Reservoir 

View map of O'Shannassy Reservoir

 

Last updated:
19 November 2020