Alta Vista Transportation Corridor Environmental Study Report November 2005 6.0 ALTERNATIVE DESIGNS The Preferred Solution to providing additional transportation system capacity through the AVTC study area, for the Official Plan horizon year of 2021, is a four-lane facility, of which one vehicle lane in each direction is reserved for High Occupancy Vehicles (HOV) and buses. A major recreational pathway would also be an integral part of the solution. The four-lane facility would link Conroy Road (at Walkley Road) at the south end of the Corridor with Nicholas Street (at the Hwy 417 interchange) at the north end of the Corridor. The next phase of the EA process identified and evaluated a set of reasonable alternative designs to implement the Preferred Solution. A detailed report entitled, Evaluation Of Alternative Designs and Assessment of The Preferred Design April 2005" (Appendix G) was prepared and circulated to the study TAC and PAC for review and comment. The following sub-sections summarize this phase of the EA. 6.1 Common Design Objectives Given the nature of the Preferred Solution, together with the locational influences and the Official Plan policy context for the AVTC, the following are the fundamental components and common design objectives of all alternative designs evaluated: The facility, will be designed as an arterial road, in accordance with its designation in the Official Plan and its intended function; The facility will be designed as a low speed arterial road, with a posted speed of 60 kph. Where possible, efforts will be made through geometric and landscape design to reduce and control travel speeds; A 3m wide Major Recreational Pathway will be provided, linking the existing City recreational pathway located on the west side of Conroy Road to the existing NCC pathway system along the Rideau River; The facility will provide an on-road cycling route linking Conroy Road to Lees Avenue, comprising a 2.0m wide dedicated cycling lanes along the outside curb in each direction; Transit supportive features will be incorporated in consultation with OC Transpo; The facility will be designed in a manner that provides for surplus adjacent lands to be utilized in accordance with their designations in the Official Plan and the Plan for Canada s Capital; Opportunities to minimize the effects on adjacent land uses associated with the facility s construction or operation will be investigated; Opportunities will be provided for the use of surplus Corridor lands for Major Open Space uses as defined in the Official Plan, including the relocation of allotment garden plots in the same vicinity; and Between Walkley Road and Riverside Drive, the facility will be designed as a Scenic Route, contributing to the continuity of the City s greenspace network and its open space character. Opportunities to design the northern portion of the Corridor (between Riverside Drive and Hwy 417) as a Scenic Route will also be pursued. The following sub-sections of this report describe the various ways of applying these design objectives to the four geographic sections which together comprise the Corridor. 6.2 South Section Alternative Designs The South Section involves the portion of the AVTC between Walkley Road and Smyth Road. This section is characterized as a wide open space corridor ranging in width from approximately 150m to more than 250m and flanked primarily by low density residential uses and parkland. This section of the Page 46
Alta Vista Transportation Corridor Environmental Study Report November 2005 Corridor is relatively void of physical features that would influence facility alignment, other than existing hydro transmission towers that should be avoided when possible. These are the main features that would influence the design and evaluation of the alternatives. In addition to the common design objectives, the area-specific design objectives for the South Section are to: Minimize effects of the operation of the facility on adjacent uses including residents and parkland users, in an equitable manner along both sides of the Corridor; Connect with Conroy Road at Walkley Road in an manner that corresponds with the existing Conroy Road alignment; and Provide safe and multi-modal connections with Conroy Road, Kilborn Avenue, Pleasant Park Road, and Smyth Road, to maximize community mobility, reduce travel distances, and minimize existing and projected cut-through traffic on local streets. The design variables for this section are based on alignment location and curvature, and median treatment. It is important to note that these designs should be considered as concepts. Specific details such as setbacks from adjacent land uses, or the curvatures selected, or the width of medians should be viewed as examples only, and not precise. The objective of the alternative designs is to enable an evaluation of them at a conceptual level, with details to follow when the Preferred Design is refined. South Section Alternative Design 1: Central Alignment with Narrow Median The defining characteristics of this alternative (Figure 6-1) are as follows: The alignment is straight and more or less in the centre of the Corridor; Minor curvatures are present to align with Conroy Road and to maintain the centrally located alignment; The median is a continuous 5.0m width between intersections; and The closest points of proximity to adjacent residential lot lines are approximately: 38m near Conroy Road; 55m south of Kilborn Avenue; and 65m at Pleasant Park Drive. South Section Alternative Design 2: Central Alignment with Wide Landscaped Median The defining characteristics of this alternative (Figure 6-2) are as follows: The alignment is more or less in the centre of the Corridor; Gentle curvatures are present and the facility flares out around strategically located wide medians; The medians vary in width from approximately 40m to 90m; and The closest points of proximity to adjacent residential properties are approximately: 40m near Conroy Road; 45m south of Kilborn Avenue; 35m south of Pleasant Park Drive; and 50m north of Pleasant Park Drive. South Section Alternative Design 3: Meandering Alignment and Narrow Median The defining characteristics of this alternative (Figure 6-3) are as follows: The alignment deviates from the centre of the Corridor as it weaves from side to side; Gentle curvatures are present, creating a meandering alignment; The median is a continuous 5.0m width between intersections; and The closest points of proximity to adjacent residential properties are approximately: 40m near Conroy Road; 50m south of Kilborn Avenue; 35m south of Pleasant Park Drive; and 57m north of Pleasant Park Drive. Page 47
HAIG SMYTH DORVAL PLEASANT PARK KILBORN URBANDALE WALKLEY CONROY LYNDA Figure 6-1: South Section Alternative Design 1
HAIG SMYTH DORVAL PLEASANT PARK KILBORN URBANDALE WALKLEY CONROY LYNDA Figure 6-2: South Section Alternative Design 2
HAIG SMYTH DORVAL PLEASANT PARK KILBORN URBANDALE WALKLEY CONROY LYNDA Figure 6-3: South Section Alternative Design 3
Alta Vista Transportation Corridor Environmental Study Report November 2005 6.3 Central Section Alternative Designs The Central Section encompasses the portion of the AVTC between Smyth Road and Alta Vista Drive. This section is characterized as an approximately 90m wide open space corridor flanked by the Ottawa Hospital Complex to the south and west, and by a high school and technology park to the east. An approximately 30m to 50m wide hydro corridor runs along the east and north sides of the Corridor. Primarily low density residential, institutional, and parkland uses exist to the north of the Hydro corridor, in the Riverview Park Community. The Hospital Woods is a valued environmental feature located in the northeast corner of this Corridor section. These are the key features that would influence the design and evaluation of the alternatives. In addition to the common design objectives, the area-specific design objectives for this section are to: Minimize effects of the operation of the facility on adjacent uses including residents, parkland users, students and employees; Provide a high degree of intersection connectivity to the Smyth Road Hospital Complex and Technology Park; Provide safe and multi-modal connections with Smyth Road and Alta Vista Drive; Protect options to locate a future east-west rapid transit facility in and/or adjacent to the Corridor (as designated in the Official Plan, yet under appeal); Locate pedestrian connections between the Riverview Park Community and the Ottawa Hospital Complex at future signalized intersections (for safe crossings); and Minimize the impact of the project on the Hospital Woods through various means such as reducing the amount of woodlot displaced, retaining a large contiguous core area, and/or providing opportunities for woodlot enhancement or reforestation. Similar to the South Section, the design variables for this section are alignment location and curvature, and median treatment. Based on these variables, four alternative designs were developed for evaluation. Central Section Alternative Design 1: Central Alignment, Narrow Median The defining characteristics of this alternative (Figure 6-4) are as follows: The alignment is straight and more or less in the centre of the Corridor; One long gentle curve is provided where the alignment transitions from north-south to east-west; The median is a continuous 5.0m width between intersections; Three intermediate intersections are provided; and The closest points of proximity of the travel lanes to adjacent residential properties are approximately 90m at Riverview Park and 200m at Browning Avenue. Central Section Alternative Design 2: Central Alignment, Wide Landscaped Median The defining characteristics of this alternative (Figure 6-5) are as follows: Gentle curves are provided where the alignment transitions from north-south to east-west, and where the facility flares out around the wide medians; The medians widen out to approximately 50m in two locations; Three intermediate intersections are provided; and The closest points of proximity of the travel lanes to adjacent residential properties are approximately 55m at Riverview Park and 150m at Browning Avenue. Page 51
Alta Vista Transportation Corridor Environmental Study Report November 2005 Central Section Alternative Design 3: Meandering Alignment, Narrow Median The defining characteristics of this alternative (Figure 6-6) are as follows: The alignment deviates from the centre of the Corridor as it weaves from side to side; Gentle curvatures are present throughout the section, creating a meandering alignment; The median is a continuous 5.0m width between intersections; Three intermediate intersections are provided; and The closest points of proximity of the travel lanes to adjacent residential properties are approximately 70m at Riverview Park and 180m at Browning Avenue. Central Section Alternative Design 4: Shared Use of Ring Road The defining characteristics of this alternative (Figure 6-7) are as follows: North of Smyth Road, the alignment veers to the west and follows the route of the existing Hospital Ring Road; The alignment follows the southern portion of the Corridor, with a slight meander; The long curve that is provided where the alignment transitions from north-south to east-west is very gentle; The median is a continuous 5.0m wide between intersections; Five intermediate intersections are provided; and The closest points of proximity of the travel lanes to adjacent residential properties are approximately 91m at Riverview Park and 220m at Browning Avenue. Page 52
ROGER GUINDON KEATS RIVERSIDE OLD RIVERSIDE CN RAIL ALTA VISTA PETER MORAND SMYTH Figure 6-4: Central Section Alternative Design 1
ROGER GUINDON KEATS RIVERSIDE OLD RIVERSIDE CN RAIL ALTA VISTA PETER MORAND SMYTH Figure 6-5: Central Section Alternative Design 2
ROGER GUINDON KEATS RIVERSIDE OLD RIVERSIDE CN RAIL ALTA VISTA PETER MORAND SMYTH Figure 6-6: Central Section Alternative Design 3
ROGER GUINDON KEATS RIVERSIDE OLD RIVERSIDE CN RAIL ALTA VISTA PETER MORAND SMYTH Figure 6-7: Central Section Alternative Design 4
Alta Vista Transportation Corridor Environmental Study Report November 2005 6.4 Riverside Section Alternative Designs The Riverside Section involves the portion of the AVTC between Alta Vista Drive and the approach to the Rideau River crossing. This section is characterized by the complexity of routing a facility that intersects with Alta Vista Drive and crosses the CN Rail line, the Southeast Transitway, Old Riverside Drive, and Riverside Drive. Existing hydro towers and the adjacency of apartment buildings are also important features to be considered. West of Riverside Drive, the alignment must have regard for a landfill area, the Rideau River Park Woods, and the Rideau River shoreline and flood plain on the east and south side of the River. These are the key features that would influence the design and evaluation of the alternatives. In addition to the common design objectives, the area-specific design objectives for this section are to: Minimize effects of the operation of the facility on adjacent uses including residents, and parkland users; Protect options to provide a recreational pathway and cycling connections to the existing NCC recreational pathway along the Rideau River; Protect options to locate a future east-west rapid transit facility in and/or adjacent to the Corridor (as designated in the Official Plan, yet under appeal); Provide safe and efficient multi-modal connection with Riverside Drive, which is a designated arterial road, in order to provide a quality connection to the Ottawa Hospital Complex from the arterial road system; Grade-separate the proposed facility by passing under the existing CN Rail line, passing over the Transitway, and terminating Old Riverside Drive with cul-de-sacs; Realign Riverside Drive and pass the proposed facility over it, to enable the rail and Transitway grade-separations while maintaining acceptable roadway grades and safe road operating conditions; Bridge structure clearances are assumed to be 4.8m minimum for the high pavement point to the bottom of structure for a road overpass, and 5.0m minimum from the high pavement point to the bottom of structure for a rail overpass; Minimize site alteration of existing landfill areas, to lessen risks and potential costs related to potentially contaminated soil and groundwater in that area; and Minimize the impact of the project on the natural features of the Rideau River, by diminishing the amount of woodlot displaced, and by curtailing site alteration along river banks and flood plain. Given the nature of the design influences and objectives for this Section of the AVTC, the range of alternative design approaches is restricted. Design variables for this section are primarily alternative means of connecting to and crossing the realigned Riverside Drive. Three alternative designs were developed as described below. As well, the original 1994 RMOC concept for this section was also reconsidered. Riverside Section Alternative Design 1: Hincks Lane Connection The defining characteristics of this alternative (Figure 6-8) are as follows: West of Alta Vista Drive, the facility passes under the CN rail line, over the transitway, and over a realigned Riverside Drive; Old Riverside Drive is terminated with cul-de-sacs along both sides of the proposed facility, as there would not be sufficient vertical separation to allow it to pass under. Emergency vehicle access is provided to the north section of Old Riverside Drive from the westbound on-ramp to the Transitway; The alignment proceeds along the west side of the landfill mound area and along the east side of a wooded area adjacent to the Rideau River; Page 57
Alta Vista Transportation Corridor Environmental Study Report November 2005 A two-way full-movement road link would be provided to Riverside Drive west of the existing Hincks Lane intersection; The alignment allows for a possible future signalized intersection to adjacent NCC lands, if required; and The approach to the Rideau River crossing is designed to align with a potential connection to Nicholas Street at the Hwy 417 interchange. Riverside Section Alternative Design 2: Hincks Lane and Frobisher Lane Connections This design (Figure 6-9) is similar to Alternative Design 1 for this Section except that two connections between the proposed facility and Riverside Drive are proposed. The first connection is a one-way westbound connection from Riverside Drive at Hincks Lane to the proposed facility. The second connection is a one-way south/eastbound off-ramp connection from the proposed facility to realigned Riverside Drive at Frobisher Lane. Riverside Section Alternative Design 3: Frobisher Lane Connection This design (Figure 6-10) is similar to Alternative Design 2 for this Section except that the connection to the proposed facility from Riverside Drive at Hincks Lane is not provided. Riverside Section 1994 Concept This option (Figure 6-11), that influenced the City s acquisition of the portion of the existing AVTC between Riverside Drive and the Rideau River, involved the westerly diversion and extension of Riverside Drive (near Hincks Lane) across the Rideau River to a connection at the Nicholas and Hwy 417 interchange. The facility would connect with Riverside Drive in a clover-leaf format just north of Frobisher Lane. Riverside Drive and the Alta Vista Parkway would then merge into the same four-lane road for a distance of approximately 600m, before diverging back into their own corridors. The 1994 design concept was evaluated by the Study Team and was considered to fail because the roadway geometry used at the time was not consistent with current standards, and because the short distance of Riverside Drive (between its westerly diversion and the Alta Vista Parkway clover-leaf connection to it) provided insufficient weaving and merging distance for combined traffic volumes that would be using it. Significant safety and traffic operations issues would exist, and the short merging of two at-capacity arterials for a 600m distance would cause the common section of road and the intersections at either end to fail. Page 58
417 LEES 417 RIDEAU RIVER RIVERSIDE ALTA VISTA NICHOLAS BRUNSWICK LEES CHESTNUT SIMCOE SPRINGHURST RIVIÈRE RIDEAU OLD RIVERSIDE CN RAIL Figure 6-8: Riverside Section Alternative Design 1
417 RIDEAU RIVER LEES 417 RIVERSIDE ALTA VISTA NICHOLAS BRUNSWICK LEES CHESTNUT SIMCOE SPRINGHURST RIVIÈRE RIDEAU OLD RIVERSIDE CN RAIL Figure 6-9: Riverside Section Alternative Design 2