Esquesing Township, of which the greatest part went to form Halton Hills, was favourably described in 1846: The town is bisected by the
Niagara Escarpment from southwest to northeast, and a significant portion of the rural area is located within the
provincial Greenbelt. Above the Escarpment, a large proportion of the rural area is classified as environmentally sensitive wetlands, and there are several sites that are licensed for aggregate extraction, for which expansion requires detailed environmental assessment. Below the Escarpment, the rural area is mainly agricultural, with the exception of an industrial area currently being developed between
Highway 401 and Steeles Avenue. The town also forms part of three watersheds: :* to the west of Acton, a small area flows toward the
Grand River :* the northern half flows into the
Credit River, including the Black Creek and Silver Creek tributaries :* the southern half flows into the
Sixteen Mile Creek The
Water Survey of Canada operates two hydrometric monitoring stations in the town, on the Black Creek below Acton, and at
Norval on the
Credit River.
Vegetation Halton Hills is located in the transition zone between the Huron-Ontario Forest Section of the Great Lakes-St. Lawrence forest zone to the north and the Niagara Section of the
Carolinian forest zone to the south. Both forest zones are part of the
Mixedwood Plains Ecozone. The natural vegetation in the Huron-Ontario Section is dominated by mixed wood forests. It is a transitional type between the southern deciduous forests and the northern coniferous forests. The forest communities of the Niagara Section are dominated by broad-leaved trees. Overall, Halton Hills consists predominantly of agricultural lands with scattered woodlands and wetlands. The woodlands are mainly deciduous forest and the wetlands are either
cedar swamp or
cattail marsh.
Endangered and threatened species American ginseng exists in the town, and is protected under the
Endangered Species Act, 2007.
Butternut trees are also threatened by the butternut
canker. The
hooded warbler and the
Jefferson salamander are also designated as threatened species.
Brook trout had been eliminated from the Black Creek watershed for many years, following the ongoing environmental disaster due to the excessive consumption of faecal mater as well as the trailer park polluting the water in the town of Erin. The trout have not returned, and anglers report that most of the fish have almost entirely disappeared from the area. and distribution of surface material in the Town of Halton Hills are the result of glacial activity which took place in the
Late Wisconsinan Substage of the
Pleistocene Epoch. This period of time, which lasted from approximately 23,000 to 10,000 years ago, was marked by the repeated advance and melting back of massive, continental ice sheets. The Niagara Escarpment dominates the physiography of the town and greatly influenced the pattern of glaciation in the region. The Escarpment, formed by erosion over millions of years, is a high relief bedrock scarp which trends to the north through the central part of the town. To the west, on the upper surface of the Escarpment, hummocky
morainic ridges deposited by glacial ice form part of the Horseshoe Moraines physiographic region. To the southeast below the Escarpment, is a smooth glacial till plain partially bevelled by
lacustrine action, which forms part of the South Slope and Peel Plain physiographic regions. The Town of Halton Hills is underlain by
Ordovician shales of the
Queenston Formation east of the Niagara Escarpment, and by
Silurian dolomites of the Amabel Formation west of the Escarpment. The escarpment face exposes a complex succession of
shales,
sandstones,
limestones and
dolomites of the
Clinton and Cataract Groups. Red shales of the Queenston Formation underlie the eastern half of the town and are generally covered by more than 15 m of glacial sediments, predominantly the Halton Till. There are several areas of thin drift cover south of Georgetown. The
quarrying of limestone has been undertaken since the 19th century, and the
lime industry was once quite prevalent. In 1886, the Toronto Lime Company had operations in Limehouse and Acton, employing a total of four draw
kilns and eleven set kilns, producing
common lime and
water lime. At Limehouse, rock from the Clinton formation yielded green and brown
shales and blue
marl, which were used in the manufacture of
mineral paints. with oil being discovered in 1912, significant strikes did not occur until 1954. The town is located in an area that is considered to be of low seismic potential, and the largest recent earthquake to take place within its limits was of
magnitude 3 on 29 June 1955. There is a
POLARIS seismic monitoring station located just west of Acton.
Climate Halton Hills has a
humid continental climate (Köppen climate classification
Dfb). The Town has two distinct climate zones: • Zone 5a - north of the Niagara Escarpment • Zone 5b - south of the Escarpment
Environment and Climate Change Canada operates one climate monitoring station at Georgetown. == History ==