This area features a well-developed incised escarpment valley with terrace valleys and broad floodplain features continuous with an extensive drowned meander valley on the Lake Ontario Plain. There is rare Carolinian flora present. The Lake Ontario Plain forest is very poorly represented in existing protected areas.

This area includes the Ball's Falls Conservation Area, and the deep valley at Balls Falls, two escarpment terrace valleys on either side of this valley and the broad, valley mouth, floodplain basin forest at Jordan. This area presents a landscape unit which expresses a wide variety of geomorphological features that are representative of this section of the Niagara Escarpment.

The major feature is the long, well-developed, deep, incised valley of the Twenty Mile Creek which, after cutting across a portion of the Vinemount Moraine atop the escarpment plain, forms a 110 foot high water falls and lower rapids; this permanent creek has formed an indirect valley into the escarpment and into the Whirlpool Terrace.

At the mouth of the valley is a broad floodplain basin with well developed annual alternate stream channelization on scree; this extends to the north towards the drowned meander valley alluvial wetlands of the Jordan Harbour area.

Contiguous with the main valley to the west is a moderately well developed terrace valley and partially buried escarpment face. On its eastern side is a more complex buried escarpment terrace slope and valley terrain.