Presentation Overview

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					                                           Presentation Overview
 DON NARROWS –                             1. Project Location and Background
  Historical and
                                           2. Historical Context – How did the Don
Existing Conditions                            Narrows Come to Be?
                                           3. The Don Narrows Today
  March 29, 2008                           4. Next Steps

                       Where is the                                             What is the
                      Don Narrows?                                             Don Narrows?
                                      • The “Don Narrows” extends ~2150 metres from Riverdale Park
                                        to Lake Shore Blvd; where the Don River enters the Keating

                                      • Engineering works in the late-1880s straightened and widened
                       Narrows          the river channel; cedar posts were inserted into the ground
                                        vertically side-by-side to create new river banks.

                                      • Steel sheet-piles were installed behind these cedar posts in the
                                        late-1940s to mid-1950s to facilitate construction of the Don
                                        Valley Parkway (DVP) and Bayview extensions. Remnants of
                                        the original cedar posts can still be seen in the “Narrows”
                                                          What is the Don                                                           Existing Conditions

•   The location of the DVP, Bayview Avenue and railways along the top of the
    river bank through the “Narrows” are frequently flooded (~2 year return
    period).                                                                                        • For years, strong
                                                                                                      community support has
•   A pedestrian trail along the west side of the river provides the only public                      been expressed to improve
    access to the Don River through the “Narrows”.                                                    the natural habitat
                                                                                                                                    A Vision By the Task Force to
                                                                                                      conditions along and within   Bring Back the Don (2001)
•   Vegetation along the “Narrows” is either absent or limited to a narrow band                       the Don Narrows.
    of opportunistic trees, grasses and shrubs – usually of the invasive variety.                   • In response, TRCA and
                                                                                                      Waterfront Toronto included
•   Heavy sediment loads (mainly sands and silts), and straight, hard channel                         consideration of “In-
    banks that are overly-wide inhibit the formation of good aquatic habitat within                   Channel” naturalization
    the “Narrows”.                                                                                    opportunities for the Don
                                                                                                      Narrows as part of the
                                                                                                      DMNP EA

•   As part of the Step 5 Activities for the Don Mouth Naturalization and Port Lands
    Flood Protection Project EA, TRCA and the Gartner Lee Limited consultant team will
    examine opportunities for improving the instream habitat conditions within the Don
    Narrows (e.g., within the channel banks and immediately adjacent to the top of banks
    between the DVP on the east and railway tracks on the west).

•   The EA team will examine:
     – Options for providing instream structures designed to improve aquatic habitat quality; and
                                                                                                                    Historical Context
     – Where vegetation can be planted or transplanted (in the case of phasing out invasive
                                                                                                               How did the Don Narrows end up this way?
     – Naturalization cannot increase the frequency of flooding on the Don Valley Parkway (DVP),
       Bayview Avenue, nor the railway tracks on the west side of the river (which are currently
       flooded almost every year in sections);
     – Naturalization features cannot increase water levels during the Regulatory Flood Event;
     – Naturalization features cannot increase the risk of failure for transportation and utility
       infrastructure running parallel to the Don Narrows.
                                                            Don Narrows
                                                 Early 1800s
                                                                                Don Narrows
                  Future Queen
                                                                                Mid 1800s
                                                                              • By 1857, the Grand Trunk Railroad had
                                                                                established a rail crossing over the Don
                                                Early to mid 1800s, the         between Palace Street and Front Street
                                                Don River originally exited     (adjacent to existing location).
                                                into the Ashbridge’s Bay      • By late 1850’s, crossings at Gerrard Street (then
   Front Street
                                                Marsh near what would           known as Bell’s Bridge) and Queen Street were
                                                become Eastern Avenue.          built.
                                                                              • Between late 1850’s and 1890, numerous other
                                                                                road bridges were built and either destroyed or
                                                                                removed south of Queen Street
                                                                              • Late 1850’s small ships and scows travelled up
  Vidal, 1815
                                                                                and down the river as far as Gerrard.

                                                                                                                                    Chewett, 1866

 Don Narrows
 Late 1800s
• Don River “Improvements” occurred
  between 1887 and 1890

• Objectives were to straighten and deepen
  the channel from Gerrard Street to the
  Grand Trunk Railway crossing.

• Goals were to provide flood protection,
  prevent ice jams and attract industry.

• The “Improvement” project was one of
  Toronto’s greatest political boondoggles in
  the late 19th century as it accomplished
  none of the goals, and took far longer to                                                                                 Cedar Pile Bank Protection along
  construct and at a much higher cost.
                                                                              Skating on the Narrows
                                                                                                                                                the Narrows
                                                                   Don Narrows
                                                   Late 1800s &
                                                    Early 1900s                        Don Narrows
                                                                                       Early 1900s
                                                           • By 1890, the Canadian    • Pollution in the Don River increased
                                                             Pacific Railway built      during the 19th and early 20th century
                                                             railway lines up the       due to agriculture, logging, milling,
                                                             Don Valley along the       industrial and animal wastes, and
                                                             west side of the Don       human sewage. Pollution accumulated
                                                             River, occupying lands     in the lower Don and Ashbridge’s Bay
                                                                                        Marsh contributing to disease
                                                             that were made
                                                             available by the Don
                                                             River “Improvement”      • The Toronto Harbour Commissioners
                                                             project.                   devised the 1912 Waterfront Plan,
                                                                                        calling for the transformation of
                                                                                        Ashbridge’s Bay Marsh into a port that
                                                                                        provided industrial, commercial and
                                                                                        park land uses.
  • By 1912, the Keating Channel was completed, which effectively diverted the Don
                                                                                      • The Port Industrial District was
    River entirely to the west, into the Inner Harbour.
                                                                                        completed between 1912 and 1952.

                                                                                                                                                Don Narrows
                                                                                                                                             Mid 1900s
 Don Narrows
 Early 1900s
                                                                                      • The DVP & Bayview             Metropolitan Toronto
                                                                                        Extension were built along    Map, 1960
                                                                                        the east and west banks of
• Major ice jam floods occurred in the Don,                                             the “Narrows”, respectively
  in February of 1918 and 1925.                                                         in the mid-1950s.
• In 1928, the Grand Trunk Railway over
                                                                                      • The Gardiner Expressway
  the Don River was raised 6 metres onto
                                                                                        was completed by the
  an earthen viaduct
                                                                                        early 1960s, providing an
                                                                                        elevated expressway from
                                                                                        the DVP to Toronto’s
                                                                                        downtown core.

                                     Don Narrows
                                     In 2002        Gerrard St.

What are the Physical
 Conditions Today?
                                                    Dundas St.

                                                     Bayview                              Queen
                                                    Extension                              St.
                                                   Subdivision                            Eastern
                                                     (CPR)                                 Ave.

                                                       Old Eastern Ave.
                                                          CN (Grand
                                                         Trunk) Bridge
                                                     Gardiner Express

                    Don Narrows                                                   Don Narrows
           Flood Levels in                               Flood Levels in
              the Narrows                                   the Narrows
                    (2 Year Flood)                                        (2 and 100 Year Flood)
                                                                  Don Narrows                                                                                                                                                           Don Narrows
                                               Flood Levels in                                                                                                                                                Channel
                                                  the Narrows                                                         75
                                                                                                                                Bed Profile of Don Narrows as Surveyed in 2003                             Morphology
                                              (2, 100 Year, and Regulatory Flood)                                    74.5

                                                                                     Elevation Above Sea Level (m)

                                                                                                                                                                                                            Height (m)

                                                                                                                     73.5                                                                                                 75
                                                                                                                      73                                                                                                  72
                                                                                                                                                                                                                               0   10   20         30    40   50
                                                                                                                                                                                                                                             Width (m)

                                                                                                                      72                                                                                                  76

                                                                                                                                                                                                             Height (m)
                                                                                                                                             Minimum Waterlevel in 2003 - Lake Ontario                                    74
                                                                                                                     71.5                                                                                                 73
                                                                                                                                             Mean Waterlevel - Lake Ontario

                                                                                                                      71                                                                                                  70
                                                                                                                                             Average Bed Slope of Don Narrows Approximately 0.09%                              0   10   20          30   40   50
                                                                                                                                                                                                                                             Width (m)

                                                                                                                            0          500                    1000                       1500       2000
                                                                                                                                                                                                                          Typical Channel Cross-Sections
                                                                                                                                    Distance Upstream From Lakeshore Boulevard (m)                                                    in the Don Narrows
                                                                                    Bed Profile of Don Narrows in 2003 with Typical Lake
                                                                                    Ontario Waterlevels and Minimum Lake Ontario Water
                                                                                    Levels (in 2003) included.

Remnants of original cedar piles from 1880s
    Don River “Improvement” Project

                                                               Don Narrows          Don Narrows
                                                Riverdale Park                      Riverdale Park
                                                Section (2007)                      Section (2007)                                                                                                   Looking downstream at Riverdale Park
                                                                                                                                                                                                    Pedestrian Bridge and Gerrard St. Bridge
                                                                                  Looking upstream from Gerrard St. Bridge
                                                              Don Narrows
                                                Park Section

                                                                                                                                                  Don Narrows
                                                                                                                                Under Gerrard
                                                                                                                                 Street (2007)
 Looking downstream from Riverdale Park
  Pedestrian Bridge at Gerrard St. Bridge

                                                                                                                             Looking downstream from Gerrard St. Bridge
                                       Looking upstream from Gerrard St. Bridge

Don Narrows                                                                       Don Narrows
Under Gerrard                                                                     Under Gerrard
Street (2007)                                                                     Street (2007)
                                                                                                                        Don Narrows
                                                                                                              At Queen
   DVP upstream from Queen St. Bridge                                                                     Street (2004)

                                             Don Narrows
                                            At Queen
                                        Street (2007)      Looking downstream from Queen St. Bridge

                                             Don Narrows                                              Looking upstream at Eastern Ave. Bridge

                                            At Queen
                                        Street (2007)

                                                           Don Narrows
                                                           At Eastern
                                                           Avenue (2004)
Remnants of Cedar Piles Under Queen
           Street Bridge
                                                               Don Narrows   Don Narrows
                                                At Eastern                   At Eastern
                                             Avenue (2004)                   Avenue (2003)

                                                                             Looking downstream from
                                                                              Old Eastern Ave. Bridge
                        Looking downstream from Eastern Ave. Bridge

                                                               Don Narrows
                                             At CN Railway
                                            Crossing (2005)

                                                                             Don Narrows
                                                                             At CN Railway
Looking upstream from CN Railway Crossing
                                                                             Crossing (2007)            Looking upstream at CN Railway Crossing
                   Looking downstream from Underneath CN Railway Crossing

                                                                            Don Narrows
                                                                            CN Railway
                                                                            Looking upstream prior
                                                                            to completion of bridge
                                                                            widening construction

Don Narrows
At CN Railway
Crossing (2007)

                                                                                                 Bala Pedestrian/Cyclist Underpass – West Don Lands

              Flood Protection Landform & Don River Park – West Don Lands

Don Narrows                                                                 Don Narrows
Other Works Adjacent                                                        Other Works Adjacent
to Don Narrows                                                              to Don Narrows
                                             Don Narrows   Don Narrows
                                   Other Works             Other Works Adjacent
                                    Adjacent to            to Don Narrows
                                   Don Narrows

Don Landing – West Don Lands

                                                           Possible Enbridge Utility Bridge Modifications

  Next Steps
         A Site Walk and Working Session to
      Discuss Ideas for the Naturalization of the
             Don Narrows will be held on

                     Saturday May 24, 2008