Royal Rouge Trail Erosion Control Project - Toronto and Region ...

Projects (Design Criteria), which seeks to reduce and eliminate existing flood, erosion and
slope instability hazards and to rehabilitate valley and stream corridors on private and public
lands (Appendix A).
1.3 Site Description
The study area is located in the East Scarborough community of Rouge, a suburb located
along the eastern most boundary of the City of Toronto. The site is bounded by Rouge Park
to the north, residential lands to the east and west, and a residential road (Royal Rouge Trail)
to the south.
In general, surface water in East Scarborough is directed to drain into the Rouge River, which
flows from the north-northwest to the southeast and empties into Lake Ontario. In the
immediate vicinity of the study area the Rouge River flows generally from east to west in the
valleylands of the Rouge Park, to the north and east of Royal Rouge Trail.
The ten single-family residences from Nos. 30 to 48 Royal Rouge Trail back onto the Rouge
Park, and are located at varying distances from the crest of the valley wall. Measurements of
the closest distance from three points on each house, as well as from swimming pools (if
present) to the crest of the valley wall are documented in Table 1.
Table 1. Closest Distance from the Residential Dwellings to the Crest of the Slope.
CLOSEST DISTANCE TO SLOPE CREST
Lot No.
West Corner of Centre of East Corner of
Dwelling Dwelling Dwelling
Pool
#30 26 20 22 -
#32 19 15 16 -
#34 17 18 21 -
#36 24 22 32 -
#38 31 11 18 10
#40 15 18 22 -
#42 23 14 22 -
#44 23 15 16 4
#46 19 14 18 -
#48 16 15 17 4
Source: Terraprobe, 2008.
The valley wall at the project site is approximately 20 to 30 metres (m) high and exhibits a
slope angle between 0.25 - 0.05 : 1 (horizontal : vertical or h : v) to about 1.1 - 1.35 : 1 (h : v)
(Terraprobe, 2008). The slope appears well vegetated with trees of varying maturity with the
exception of slope segments most severely affected by the erosion.
In the vicinity of the project area, sections of the slope are saturated several metres down
from the crest of slope and in several areas, gullies have formed to channel the water down
to the floodplain at the base of the slope. There is no evidence of water being directed from
pools or drains over the slope crest, and it is assumed that the groundwater is from natural
sources (rainfall etc)
The predominant vegetative community found on the valley wall adjacent to the project site is
a Hemlock-hardwood mixed forest with common species such as; Eastern hemlock (Tsuga
4
Project Plan
Toronto and Region Conservation Authority
Royal Rouge Trail Erosion Control Project January 2010