Mississauga covers 288.42 kmē of land fronting a 13km shoreline on Lake
Mississauga is bound by Oakville and Milton to the west, Brampton to the
north, Toronto to the east, and Lake Ontario to the south. Halton Hills borders
Mississauga's north-west corner. With the exception of the southern half of the
border with Toronto (Etobicoke Creek), Mississauga shares a land border with all
previous mentioned municipalities.
Two major river valleys feed into the lake. The Credit River is by far the
longest with the heaviest flow, it divides the western side of Mississauga from
the central/eastern portions and enters the lake at the Port Credit harbour.
This indented, mostly forested valley was inhabited by native peoples long
before European exploration of the area. The valley is protected and maintained
by the Credit Valley Conservation Authority (CVCA).
Etobicoke Creek forms part of the eastern border of Misssissauga with the
city of Toronto. North of there is passes through Pearson Airport, where there
have been two infamous aviation accidents where aircraft slid into its banks.
This valley experienced some heavy flooding with some homes along its edge being
swept into the lake as a result of heavy rains from Hurricane Hazel. This creek
and its tributaries are administered by the Toronto and Region Conservation
Most land in Mississauga drains to either of the two main river systems, with
the expection of the smaller Mary Fix Creek which runs roughly through the
center of Mississauga entering the lake just east of Port Credit. Some small
streams and resevoirs are part of the Sixteen Mile Creek system in the far
north-west corner of the city.
The post-glacial Iroquois Shoreline roughly follows the Dundas Street
alignment, although it is not noticeable in some places and in others the
shoreline affords a view of downtown Toronto. The land in Mississauga in general
slopes gradually downward from almost 190m ASL in some northern spots to lake
level (76m ASL), a 110m difference over an averaged 15km distance.