This article continues a series reviewing the open houses held by Metrolinx about the Draft Environmental Impact Assessment Review (EIAR) for the Ontario Line. Here I will focus on the section of the route from Gerrard north to Eglinton (Science Centre Station), and in a third article to follow, I will review the southern section from Gerrard to Exhibition.

See also:

• Ontario Line Environmental Assessment Open Houses: Part I – General Thoughts
• Open House of February 22
• Open House of February 24

The material here is organized by topic rather than in the order that questions were posed. Some topics and locations had no information beyond the basic Metrolinx presentation either because nobody asked, or because a pre-submitted question was not chosen by the moderator.

Although Metrolinx claimed that it would answer all of the pre-submitted questions through the meeting web pages, as I complete this article on March 11 few replies have been posted.

In my consolidation of the discussions, there are three sections tagged as below:

• Q: A précis of the question asked (this might consolidate related questions).
• A: A précis of the Metrolinx response
• Comment: My comment on the Q&A, if any.

I make no excuses for whatever Metrolinx might have said, or omitted, in their answers. Nobody is quoted by name, but if anyone thinks I have misrepresented their position, please leave a clarification in the comments.

This is a long read condensed from about four hours of meeting recordings.

Thorncliffe Park

Originally, I planned to include a discussion of Thorncliffe Park in this article, but that section kept growing along with the complexity of the issues. I will publish a separate piece on this in coming days.

An overall urban design exercise is needed for Thorncliffe, not just for the immediate location of the line and the Maintenance and Storage Facility (MSF). This would include considerations such as:

• future housing growth,
• the use of land such as parking lots and the low-rise industrial/commercial buildings,
• how services will be provided if there is even more population added to an already crowded area,
• urban design issues including streetscape and parks,
• how Thorncliffe relates to the south end of Leaside even though they are separated by the railway.

Many comments and responses to date have only addressed individual components of this rather than looking at the whole. This should not be just an exercise in threading a transit line from the Don Valley to the Eglinton.

Traffic Effects

An important issue for the construction period received comparatively little discussion, probably because the effects downtown received much more publicity.

Although there is a Traffic and Transportation Analysis in the EIAR, it contains detailed plans showing station layouts, construction laydown areas and haulage routes only for the downtown portion of the Ontario Line. This material was produced to obtain Toronto Council’s approval of Metrolinx plans. Effects on the north segment are described only in text. Unlike the downtown segment, the road network serving the northern segment has fewer options to relocate traffic.

See: Ontario Line Downtown Construction: VI – Executive Committee Debate and site-specific articles linked there.

Here is the description in the presentation deck:

Traffic and Transportation

Construction will be carried out in a safe manner and work sites kept separate from the public, by diverting pedestrian and vehicular traffic around work zones, and using effective wayfinding.

Approach to maintaining traffic flow
• Construction at Pape and Cosburn Stations will aim to avoid main thoroughfare routes, minimizing disruptions to traffic in the area.
• The crossover construction near Sammon Avenue will be planned and staged to minimize the duration of traffic diversions.
• The elevated guideway will be constructed adjacent to main routes where feasible avoiding major disruptions to Overlea Boulevard and Don Mills Road.
• A grade separation will be constructed at Beth Nealson Drive with traffic temporarily rerouted from the work zone.
• Bus terminals at Pape and Science Centre stations will remain operational throughout construction to avoid any service disruptions.

Source: Metrolinx Presentation Deck February 22 & 24, 2022

In practice, details listed in the Traffic and Transportation Analysis are more substantial. Some of these will be long-lasting, while others are short-term.

• Partial closure of Pape at Sammon for road decking in support of the crossover construction at that location.
• Full closure of Cosburn west of Pape for road decking as part of the station construction. This will require diversion of transit service.
• Restrictions at Pape Station loop for buses and pedestrian access. “The number and location of bus bays are expected to be modified. The roadway connectivity of the bus loop is still being evaluated.”
• Full closure of Beth Nealson Drive for 1.5 years for grade separation of the road from the Ontario Line by a new underpass will sever the eastern link between the Leaside industrial area and Thorncliffe Park. This will affect the 88 South Leaside route.
• Utility relocations north of the Gerrard Portal will require bus route detours on Riverdale and Carlaw Avenues.
• Erection of elevated guideway structures will require lane closures on Millwood Road, Overlea Boulevard, Don Mills Road and Eglinton Avenue and some full weekend closures where the guideway crosses roads.
• Construction of the Minton Portal will require off peak lane closures of the DVP northbound, and full weekend closures will be needed for erection of the Don Valley bridge.
• The Science Centre Station bus loop will be restricted by guideway construction.

• Sidewalk closures, lane closures or width reductions on Bain Avenue, Gowan Avenue, Gamble Avenue, Pape Avenue, Gertrude Place, Lipton Avenue, Minton Place, and Hopedale Avenue.
• Sidewalk, lane and road closures for utility relocations just north of the Gerrard portal on Langley Avenue, Riverdale Avenue, Pape Avenue, and Carlaw Avenue.

• Parking will be restricted in several locations including the Science Centre, and the TPA lot at Pape Station will be closed.

• Effects on cycling routes are yet to be confirmed.
• Cyclists will be affected by lane closures and increased traffic volume on what remains.
• Trails in the Don Valley and south of the Science Centre will remain open, but with temporary intersections where they cross construction roads. Short-duration closures are likely during erection of bridge elements.

• Hauling routes for the north segment have not yet been defined, but these could “result in increased delays and travel times along designated haul routes”.
• Access plans for emergency services and deliveries to the north segment have not been defined.

Construction Staging

Q: What will be the construction staging at each site for construction and pre-service fit-out? Will there be hazardous materials?

A: The type of materials at sites will be the usual type of thing one would expect for a construction site. Metrolinx will ensure that materials are stored safely.

Comment: As noted above, information for the north segment of the line is not included in the Transportation and Traffic appendix.

Q: How much will be removed from tunnel construction at Minton Place, how many truckloads?

A: Minton Place is a portal and emergency exit, but is not a site for removal of spoil from tunnel boring. Spoil from the north tunnel will be removed at the Gerrard site. Information on volumes and trucking are in the construction backgrounder. Metrolinx will try to access sites via major roads like Gerrard.

There is also a construction site at Pape and at Cosburn stations.

Comment: The removal plans are in the Transportation and Traffic appendix, but they are much more detailed for downtown stations than for the northern segment.

Q: Will spoil be removed 7×24?

A: There will be two shifts of tunneling with the third (overnight) shift used for maintenance. Spoil will come out 16 hours/day. If there is a need to tunnel overnight, spoil will be stored to concentrate removal during the daytime. An alternative would be to have an enclosed building, but that is not likely.

Q: What closures do you expect on Pape north of O’Connor? Do you expect to close the DVP?

A: Metrolinx is working with City Transportation Services on road closure plans for the north section. These will come to council for approval of all closures longer than one year. In this section, few closures are expected because stations are shifted off of the road alignment. DVP closures would be at night during existing maintenance shutdowns. Closures for hoisting beams would be “quite limited in nature”.

Comment: See the section above about the Transportation and Traffic appendix. There will be road restrictions on Pape at Sammon, a closure of Cosburn west of Pape and temporary closures at various locations between Minton Place and Science Centre for erection of the elevated guideway. The report is quite clear that some temporary closures would be weekend-long, not overnight.

Q: When do we find out the construction impacts at Danforth and at Cosburn.

A: Metrolinx is already working with BIAs at Pape/Danforth. This is a difficult site, but the construction impact will be minimized because of the alignment shift. There will be Construction Liaison Committees (CLCs) for ongoing co-ordination with businesses and communities.

Comment: The detailed plans for Pape Station have not been published. This is also likely to become a Transit Oriented Community (TOC) site for development by Infrastructure Ontario, but there are no details yet. Construction will affect bus loop operations and some surrounding streets, and there will be a cut-and-cover site at Sammon and Pape for construction of a crossover between the northbound and southbound tunnels.

Q: When will the CLCs be formed?

A: North segment construction will not happen until 2023, whereas in south it is happening now. A CLC acts as a sounding board for virtual open houses. The goal is to get them up and running in 2022 to start getting feedback. Metrolinx expects to set them up by year end for the north area, maybe by late summer.

Q: (From a Minton/Hopedale resident) Where have you seen similar applications of this technology for a partly over/underground line in a similar climate to validate that projections will happen. What changes have taken place in this plan over past 18 months based on Environmental Impact Assessment (EIA) feedback?

A: An EIA is a constant feedback cycle. Locations where changes were made include:

• Don Valley to Thorncliffe Park alignment was improved by running on the north side of Overlea vs the middle of the road.
• Near the CNE some corners were smoothed out coming into Bathurst Stn.
• The alignment was shifted at the NE corner at Don Mills/Eglinton for connectivity to the bus transfer station. Also this incorporated the Eglinton crossing in the OL project so that a future interruption for extension will not be required.
• A lot of sites have been moved out of roadways to improve station construction. Sequential excavation (mining) will be used at some sites rather than open cut construction / SEM rather than open cut // Three companies have looked at JC noise work to validate

Noise and vibration models use industry (US) standards, and the modelling files have been vetted by Metrolinx’ regulator (the Ministry of the Environment) who are “confident” of the results.

Process

Q: Why is the review period so short compared to requirements in EA legislation?

A: The Ministry of Environment code of practice is a general document. For transit projects there is a separate Transit Project Assessment which has its own guide with a 30-day review period.

Comment: The assessment process for “priority” provincial projects was also reduced by the Building Transit Faster Act.

Q: How do people track that mitigations promised are actually met.

A: Some specifics are already announced such as vibration controls. Others will be identified during construction planning, so mitigation details to come later.

Property Effects

Q: What does an easement under a home mean? How is compensation determined? What is it compensating for? What is the effect on renovations?

A: The value of an easement is based on an appraisal report by a 3rd party expert on a case by case basis. Owners can have their own appraisal done at Metrolinx’ expense.

Comment: Metrolinx did not answer the questions posed. For readers unfamiliar with the term, an easement can have two forms: temporary and permanent. A temporary easement could be for something like occupying property for construction access. A permanent easement could be for a tunnel running under land that Metrolinx does not own.

Q: On Pape, our house sits on sand and the water table is only 20 inches down. Can we they get an engineering assessment of effects? Is this something Mlx does?

A: Metrolinx needs to talk to the property owner to better understand their location vs the project. Property-specific conversations will be done via direct contact between owners and Metrolinx.

[From a separate part of the discussion] Metrolinx is working on satellite imaging of entire alignment to get current conditions and measure the height of ground & buildings. This will create a profile to measure whether and how much buildings move. This already happens seasonally and satellites pick this up. This will give a baseline for all seasonal movements so that Metrolinx can see if works in the area are affecting ground and buildings.

Q: What is the status of existing condition reports?

A: Metrolinx will perform precondition surveys on buildings that are likely to be impacted by construction, and will not just rely on satellite info. That tool is good overall, but they will do more detailed work including monitoring points.

Noise & Vibration

Q: Health impacts are both acute and chronic, and there are studies setting acceptable levels, notably from the WHO. What will Metrolinx do to ensure dB levels do not exceed daytime/night levels of 55/50 dBA respectively.

A: “Management of noise is top of mind for us.” Metrolinx worked very closely with MOE, and criteria are provided by them. They are different for things like the Maintenance and Storage Facility (MSF) and for train movements. All targets refer to existing noise levels, and typical levels around the OL are higher than the 50/55 dBA levels cited in the question. It is the existing levels Metrolinx is working to stay within, and these will be included as criteria in contracts. OL trains will be quieter than existing road traffic.

Comment: The basic goal, according to Metrolinx, is to avoid making the situation worse than it is now, more specifically not to raise the average noise level by more than 5 dBA. As per their own study, this cannot be achieved in all locations without some form of mitigation, and even then this could be a challenge for some areas such as buildings overlooking a surface or elevated guideway.

Q: The EIA says there would be an increased level of noise at portals. The speaker has stood beside TTC portals as a test. If the actual experience is that noise levels are not acceptable, what monitoring and correction will be provided?

A: The operating conditions will be monitored, and Metrolinx will do further investigations if needed. Problems can be caused, for example, by wheel flats, but through good maintenance Metrolinx will limit these. Noise problems are usually due to maintenance (i.e. fixable) as opposed to a base level condition. Automated trains have a large amount of data collection including flat detection. Systems will notify operators if there are problems. Braking profiles are designed to not create flats in the wheels, and with automatic operation these profiles will always be used.

Comment: Decades ago, when the Scarborough RT was touted by the province, there were claims of low noise levels because the wheels would not be used for the primary tractive effort. (The linear induction motors interact with the reaction rail on a contactless basis.) However, designers missed the fact that wheels bounce for various reasons including rail irregularities. This sets up a condition of rail corrugation similar to that found on dirt roads, although on roads the corrugations are more widely spaced because rubber tires bounce at a lower frequency. In turn this generates load wheel noise and it is a self-perpetuating condition. The situation is compounded on the SRT by the use of small, lightweight wheels.

The SRT requires constant rail grinding to maintain quiet operation in residential areas. Metrolinx’ confidence that they can control noise by avoidance of flats will address some of the problem, but this is an integral part of railway technology affecting both the existing subway and streetcar networks.

Q: Will noise be below 55/50 dBA? How will buildings on Pape be affected? What might be the effect on conversions in progress (Commercial to Residential)?

A: Metrolinx repeated the explanation of noise level profiles and that regulatory guidance allows for up to a 5dB increase over existing levels, whatever those might be. Metrolinx targets a 0dB change. See Appendix A6 for tables of existing and predicted conditions.

On Pape, rubber “pucks” will be under the track structure to limit noise and vibration to nearby buildings.

Comment: The Noise and Vibration Report recommends different mitigation (including none at all) to various sections of the line depending on the amount of dampening required to stay within the target levels. Anyone asking about a specific location should cross-check this info.

Specifically for Pape Avenue, the most common recommended mitigation is a “Light Mass Spring System” which offers less reduction that the floating slab technique Metrolinx cites repeatedly. See table 7.5 in the N&V Appendix for Pape, and tables on surrounding pages for other sections.

In fact, floating slab is only recommended in a few locations, and notably through Thorncliffe Park, no mitigation is recommended at all. This is a direct contradiction of Metrolinx presentations, and they should clarify their position on what will actually be built. Retrofits are complicated to install after the fact.

See tables beginning at 7.4.2 Impact Assessment Results on page 139 of the N&V Appendix pdf (numbered as page 112).

Q: Crossovers and switches will have an effect on noise and vibration. There are locations where these appear to be missing from the base map. What is the effect on noise modelling?

A: At the Science Centre, the crossover will be north of the station for a far end turnarond. If the line is eventually extended, the turnback would be done at the new terminus.

Comment: It does not matter where the actual terminus will be as a crossover at Science Centre would remain in place for emergencies or for scheduled short turns service. The base map (using the version in the Noise and Vibration appendix) appears to be missing some of the special work, and this begs the question of whether the model reflects the actual design. The locations on the base map are:

• West and East of Exhibition Station
• East of Queen Station
• In the West Don Portal
• North of Pape Station (Sammon Ave)

No special trackwork is shown on the N&V base map at Science Centre nor for the junction with the MSF, although this track does appear on presentation maps.

Q: Re noise at Pape & Gerrard by Pape school: what will the depth be near school just north of the portal as compared to Pape Station?

A: The transition from above to below ground will have a fairly steep grade, and the tunnel will not be as deep as at Pape Station. The portal area will be another TOC site – IO is thinking about this. There won’t be any perceptible noise and vibration at the school because of the deep dive plus mitigation. Because the surface level rises northward on Pape, the tunnel gets deeper more quickly than just from its own grade. It will be 7m underground at the school.

Comment: If this will be a TOC development site, then Metrolinx should address noise that will be radiated from the open track structure at Gerrard. Some but not necessarily all of the OL structure might be covered by future development, but not the station which sits on a bridge over Gerrard and Carlaw.

Q: At the Don Valley there will be fairly constant noise from bridge because trains run frequently. Is there any thought of mitigation such as the subway bridge at Rosedale Valley Road?

A: Metrolinx repeated its claim that new subways are quieter because there is no hard braking or acceleration, continuous welded rail and sound deadening technology under the tracks. A lot is available today that was not available when the subway was built.

A few years ago Metrolinx was collecting noise level data. Existing noise conditions are similar to urban environments such as road noise from DVP. OL trains will be quieter than existing subways. One of the immersive sound demonstration locations is at the north end of Minton Place. Metrolinx is not proposing an enclosure because the source is quieter.

Q: In Thorncliffe Park, the report says that vibration levels are anticipated to be low and not cause structural damage. How many types of structures have been considered?

A: Metrolinx will develop a communications protocol re construction work and a complaints procedure.

Q: What is a “timely” response?

A: Site specific mitigation and monitoring includes a two tier alert sytem. There will be advance notice of expected work. The timeline for mitigation will depend on the root cause as mitigation materials might have to be acquired.

Q: How do you determine where “sensitive receptors” are and monitoring locations will be? [Note that “receptor” is a term used in studies as a generic name for places where there could be N&V effects.]

A: A receptor can be any location that could be affected by noise and vibration. First there is a desktop review of the line, then field work to identify receptors. These are grouped, and those nearest the project are modeled in detail. This was done both for construction and for operations. The same locations were not necessarily used in each case because the sound origins and effects differ. “Receptors” were for modelling purposes and monitors will track actual conditions through construction. This information will be shared via the CLCs.

Q: In the N&V study, pdf page 107 has a chart [Table 5-9] with day/night existing/future Lpassby values for for Hopedale. How was the 64dBA level determined? How will Mlx ensure that noise levels stay at WHO/MOE 55/50 dBA levels? What mitigation will be provided?

A: Different models and lenses are used for noise. One of the provincial requirements is LPassby [the sound profile of a passing train]. The table shows what sound will be at various locations. Metrolinx looks at the existing noise environment. Where it is very quiet, MOE requires the 55/50 levels, but at most urban locations the existing levels are higher. The Metrolinx target is as quiet as possible. Averages will be 56/51 (day/night) and so very similar to the existing noise environment.

Valley Crossings

Q: How will construction protect cycling and pedestrian routes in ravines? How do the plans work with the city’s Vision Zero and Ravine strategies?

A: The plan supports Vision Zero by reducing traffic and increasing transit use, and by providing an “effective alternative” for residents.

Comment: This line is a piece of Metrolinx mythology than simply cannot go unchallenged. Many, many studies including Metrolinx’ own regional plan have shown that, at best, all of the transit projects they are building will only keep traffic at existing levels. The reasons for this are quite simple: demand exceeds supply, and is constantly fueled by population growth. Vision Zero requires fundamental changes beyond building a few more rapid transit lines.

A: The OL fits well with the Ravine Strategy. Metrolinx will minimize impacts, and compensation activities go above and beyond regulatory requirements. The Walmsley Brook area [the valley separating Thorncliffe Park from Leaside extending west from Don Mills Road] is in a degraded state and will be enhanced with bank protection. Metrolinx will partner with TRCA for “voluntary compensation” in priority areas in the Don Valley.

Comment: Note that, as with other locations where Metrolinx projects have an environmental effect, the compensation does not necessarily occur at the same location. The premise is that, on average, the environment of the city or GTA gets a bit better.

Q: What will be the effect on wildlife? Near Minton Place there is a large forested area with a herd of deer. What will happen to them? Is there someone responsible for monitoring wildlife impacts?

A: Metrolinx will implement “best management practices” including wildlife fences, planning work around timing/seasonal cycles and design to minimize impacts. There will be limited tree removals and post-construction they will restore the area to past conditions. Metrolinx will require environmental inspectors as part of their contract with the builder.

Q: Will the bridge over the Don Valley be built in the valley and concurrently with other projects.

A: The schedule will be developed with the contractor. The bridge will be built out from a central pier, subject to confirmation by the proponents, with four piers erected from the valley floor. They will be 50-70m tall, and their locations are on the map in the EIAR executive summary.

Q: How will Metrolinx measure problems such as subsidence?

A: Metrolinx talked about Zones of Influence (ZOIs) and precondition surveys, project output specifications and strict settlement criteria. Tunnels are very deep and/or under roadways, and Metrolinx claims that these are locations where there will be no subsidence. Nonetheless, they will use GPS satellite measurements of all building positions and the latest tunnel boring technology to prevent settling when they are in soil.

Pape Station

Q: What is the precise alignment of the Pape tunnel? Can you talk about vibration impacts?

A: Pape is a vital station. The alignment has been shifted out of the street corridor east and north to maintain traffic during construction. The line is very deep under Pape Station, and noise and vibration will be “very negligible”. Modelling shows that this will below a perceptible level due to the deep tunnel and mitigation. An immersive demo of noise in a nearby basement is available online.

Q: Our property backs onto what looks like a staging area at Pape Station, and there is a laneway that is the access to parking garages. What sort of noise can we expect in the staging area? Will there be restrictions on work hours? Will there be hazardous materials? What will be the site security? What are plans for the use of the lot later?

A: This station site is part of Infrastructure Ontario’s TOC program. Detailed proposals will come out in due course. There will be a Pape Station CLC in about 6 months, and it will operate on a rolling 2 month basis.

Work will start with on the TTC station to facilitate continued bus operations, then utilities, then selective demolition. There will be minor works in 2022, more in 2023. Station construction will begin in 2024.

Construction hoardings will be 10ft which is normal (this varies depending on local standards). Hazardous materials are generally not allowed to be stored on site. Metrolinx does not want to bring dangerous materials onto the site.

Q: (A resident of Hazelwood Ave S of Pape/Danforth) There is no profile showing the depth of the line. What is the depth to top of tunnel? What is the expected post-construction noise levels? What reactive measures are available post-construction to remediate?

A: The tunnel is about 30m deep at Pape Station. Metrolinx is “quite confident” that noise and vibration mitigation will make for “negligible transmission”. The point about flat wheels being the major problem (see above) was repeated.

Gerrard Station

Q: Gerrard/Carlaw will be covered by two bridges, and there is a massive staging area. How will you do traffic management and provide for the fire station and local businesses? The dog park dog park was to be replaced but this appears to have disappeared. We are worried that it will be impossible to move for years.

A: Metrolinx will occupy existing dog park for construction. We are working with Toronto Parks to find a temporary or permanent dog park. When the work is done, the park will be larger.

The launch shaft is in the No Frills plaza. The existing GO bridge will remain. OL bridges are west of there, and they are long spans which will partly be for the station and partly for the lead to the portal. Work will be staged from the dog park plus extra land. [Metrolinx is acquiring land at the east end of First Avenue where it abuts the dog park.]

There will be a traffic management plan including emergency services and for trucks carrying construction materials.

Q: Having now read about 8000 pages of various reports, this line belongs underground. There are impacts especially at Gerrard Station: a seniors’ home and Pape school. The mitigated noise levels here for day and night tunelling is 82 dBA. The lowest level in the area is 71 dBA. Metrolinx is over its own target levels. What mitigations did you use in the model, and what further mitigations will you use during construction? How long will you need this staging area?

A: Metrolinx modelling assumes a 5m barrier around the site plus enclosures around equipment. They acknowledge that they are above their targets at some places and need to look at how to further mitigate this.

There are other locations along the project where the projected noise levels might be over the targets. Metrolinx will set rules for the contractor and it is their job to figure out how to achieve them.

The North Civils contract starts in 2024. First there will be construction of the launch shaft which will take about 9 months. Then the tunnel boring machines much be assembled. They will travel 10-15m per day, and with 2.6km of tunnel, this will be about 200 days’ work. Overall, this will be a few years from start to finish.