Christie Point TIA Review (Opus International)

Christie Point TIA Review

In response to your request, Opus International Consultants (Canada) Limited (Opus) has conducted a review of a Traffic Impact Assessment (TIA) conducted by Bunt & Associates. Our review consisted of the following:

1. Site Visit: Opus staff drove along Island Highway in the morning, mid-day and afternoon peak hour as well as observed traffic queue lengths at the intersection of Island Highway/Craigflower Road at Admirals Road intersection.
2. TIA Report Review: Opus reviewed and made notes on the following:
   • Traffic count data and historical traffic growth rate assumptions;
   • Trip generation assumptions and future background traffic assumptions;
   • Site parking assumptions;
   • Appropriateness of signalization of Shoreline Drive (from a proximity perspective with Admiral Road);
   • Merge lane length recommendations.

1. Existing Network Conditions

The TIA was conducted by Bunt & Associates for the Island Highway/Craigflower Road at Admirals Road and Island Highway at Shoreline Drive intersections for the afternoon peak hour only. The Island Highway/Craigflower/Admirals Road intersection is signalized with the following lane configurations:

• Northbound (Admirals Road) double left turn lane, one through/right turn lane;
• Southbound (Admirals Road) channelized right turn lane, two through lanes and a left turn lane;
• Westbound (Craigflower Road) through/left turn lane, through/right turn lane which merges beyond the intersection east of Shoreline Drive;
• Eastbound (Island Highway) left turn/through lane, through lane and right turn channelized lane.

The Island Highway at Shoreline Drive intersection is a stop controlled T-intersection where the outside westbound lane on Island Highway terminates as a right turn onto Shoreline Drive and the Shoreline Drive southbound to eastbound left turn movement is protected by a median on Island Highway. The intersection is also approximately 150 metres from Island Highway/Craigflower Road at Admirals Road intersection.

The Bunt report stated the Island Highway network is nearing capacity during the afternoon peak hour. This is consistent with our findings during our on-site observation of the intersections on February 3, 2017 for the PM peak hour. The findings of our site visit indicates major delays in the westbound, northbound and southbound directions at Island Highway/Craigflower Road at Admirals Road intersection from approximately 3 pm to 5:30 pm.

During the morning peak hour, there were delays along Island Highway but the bottleneck occurred west of Admirals Road near Helmcken Road. Traffic is steady in the eastbound direction and queues were no more than 10 vehicles at the Island Highway/Craigflower Road at Admirals Road intersection in all directions.

We document these findings in Appendix A.

2. Trip Generation

The TIA was based on redevelopment of the site from 161 to 517 rental units of similar size and number of bedrooms. This number of units may be reduced to 478 and the number of 2 or 3 bedroom units has not yet been defined by the developer. The trip generation rate used by Bunt was based on one day count and estimated at 0.28 trips per unit for the afternoon peak hour which is lower than the trip generation rates established in the ITE trip generation manual, a widely used industry standard. The primary reason for the use of the lower rate was based on a demographic assumption of higher retirees and home based businesses as well as based on promoting alternative transportation strategies such as cycling and transit with less reliance on the vehicle for travel. This represents a ‘best-case’ scenario. As a conservative measure, our team believes a higher trip generation rate similar to the one presented for mid-rise apartments or condo/residential row house in the ITE manual of 0.39 to 0.52 should be considered because the introduction of more rental housing could change the demographics of the area.

The change in the number of trips from the original analysis using a lower number of units for the development but higher trip generation rates is shown below. The table shows a trip rate of 0.39 would increase the number of trips predicted for this development by approximately 40% more than the original report when using the lower number of units forecasted.

Table 1

*removed trips generated from the existing 161 units as these units will be demolished.

Based on Bunt’s assumptions, the increase in traffic from Christie Point redevelopment is expected to increase the number of vehicles from existing by approximately 1.8% at the intersection of Island Highway/Craigflower Road/Admirals Road. The Bunt report states this increase is considered negligible and a relatively modest net impact will occur from a traffic capacity perspective compared to the current conditions. This is correct as existing traffic is causing the significant delays along the network in the afternoon peak hour. Changing the number of trips will likely not change the results significantly at Shoreline Drive for left and right turn movements as the existing LOS was modelled at F during the afternoon peak hour and will continue to be modelled at F when development is added if there is no mitigation measures implemented. As stated in the Bunt report, the limitations of traffic counting when there is a metering effect caused by the lane drop at Shoreline Drive will likely not accurately model the field conditions of the signal at Island Highway/Craigflower Road/Admirals Road intersection. Modelling will also likely not change the results of this intersection if there is a change in the trip generation rate.

The modelling analysis was not completed for the morning peak hour where higher number of southbound left turn movements for work trips into downtown Victoria will likely occur from the additional housing units. Although the afternoon peak hour shows there are capacity issues near the proposed development along Island Highway under current conditions and the likely reason for the analysis being completed for this peak hour only, the impact of the morning peak hour should also be considered in the analysis to show this peak period would not significantly be impacted by the additional development.

The redevelopment will cause the southbound left movement from Shoreline Drive to Island Highway to fail further than the current situation as more trips are anticipated during the morning and afternoon peak hour from this development at Shoreline Drive. Our site visit found that drivers trying to turn left out of Shoreline Drive during the afternoon peak hour could only maneuver when westbound vehicles stopped to let the drivers make the turn.

3. Future Background Traffic and Total Conditions

The Bunt analysis did model future background and total traffic conditions where 2016 data was increased at a 1.5 % annual growth rate to the opening day of development (2018) and 10 year horizon (2028). However, there was no basis provided on how this growth factor was derived. The report later disregarded future background traffic increases and did not show the results of modelling the future total conditions with mitigated solutions stating these volumes are overstated as the network in its current configuration did not have the capacity to add such an increase in background traffic. Essentially it focused on showing modelling results for mitigated solutions caused by the development with existing traffic while ignoring any future background traffic increases. The results of the background traffic increases with the development for the mitigated solutions should also be included in the traffic modelling analysis.

We reviewed historical information from the CRD traffic count website (https://www.crd.bc.ca/about/data/traffic-counts) from 2012 to 2015 for Island Highway near Admirals Road and found the traffic was consistent in 2012 and 2014 east and west of Admirals Road but increased in 2015 west of Admirals Road. However, there is not enough data to determine a growth or declining trend and we believe until there is a policy in place limiting development, background growth based on an agreed upon assumption with the Town should be considered in any analysis. The 24 hour count also provides an indicator of how much more traffic the road can handle. The numbers below indicate the single lane roadway per direction is handling volumes more in line with arterial type roadways and likely the reason for drivers travelling at a crawling speed during the afternoon peak hour. The addition of the McKenzie Interchange to the north at Highway 1 may change the traffic distribution and monitoring is recommended.

Table 2 – Island Highway West of Admirals Road – 24 Hour Count

Table 3 – Island Highway East of Admirals Road – 24 Hour Count

4. Parking

The current off-street parking bylaw is a minimum of 1.5 parking spaces per dwelling unit for row houses or apartments of 1 to 2 bedrooms and 2 spaces for three bedroom apartments. According to the Bunt report, the current demand at the site is 1.32 spaces per unit. There is also 0.14 visitor spaces per unit for a total of 265 on-site parking spaces. The report states that renters have lower vehicle ownership than homeowners and therefore recommends to lower the rate to one space per unit and to use a rate of 0.15 for visitor parking spaces.

However, as the ratio of 3 bedroom vs. 1 or 2 bedroom units is not yet defined by the developer for the site, a parking rate of 1 stall for a 3 bedroom unit would be quite low and we believe the rate should be adjusted to at least 1.5 per unit for 3 bedroom housing type units and a rate 1.3 for 1 to 2 bedroom type units. The visitor parking rate of 0.15 seems appropriate.

Bicycle stall parking was also discussed in the report. The increase of Class 1 secure spaces for bicycles from 1 to 2 spaces per unit seems reasonable and in line with achieving sustainable transportation strategies.

5. Transportation Demand Management

The Bunt report provided a discussion of incentives to reduce vehicle use and promote sustainable transportation modes. The improvement of trails are also important in promoting sustainable transportation options. A commitment of improving the trail from Shoreline Drive at the school to Island Highway should also be considered if this development proceeds. Improvements to this trail, such as paving the surface, will make cycling more attractive for people looking to travel west along Island Highway and back to the development site.

6. Intersection Control and Lane Configuration of Shoreline/Island Highway Intersection

6.1. Intersection Control

The final recommendation in the TIA report was the introduction of a full traffic signal and pedestrian crossing at the Island highway at Shoreline Drive intersection. The recommended spacing between accesses for collector type roadways is around 60 metres and for minor arterials within developed locations around 200 metres¹ and to ensure mobility. The spacing between Shoreline Drive and Admirals Road is 150 metres. If the intent is to treat Island Highway as a collector road to just east of Shoreline Drive, the current speed limits of 50 km/h and 30 km/h for the school zone are acceptable as is the intersection spacing. Electronic speed reader boards should be considered to help with enforcement of the school zone speed limit. The Bunt Report classified Island Highway as a major arterial. This classification would likely require re-consideration of the recommended traffic signal at the Island Highway with Shoreline Drive Intersection. Therefore Opus recommends Island Highway near the school be considered a collector road.

Signalization for collectors at approximately 215 to 400 metre intervals depending on the cycle length for a running speed of 50 km/h is generally acceptable. It is preferable to space signals farther apart for arterial type roadways to improve progression with a spacing on the order of 415 to 695 metres depending on cycle length and running speeds of 50 km/h². If running speeds are lower at 40 km/h, then signal spacing on arterials can be reduced to between 335 to 555 metres. Running speed is defined as the 85th percentile speed of all vehicles along a specific roadway³ (usually between two major intersections) as determined by distance and running times. Running speeds are impacted by traffic volumes.

The Bunt report indicates that signals are not warranted based on the current vehicular volumes with or without the development volumes. However, there was no warrant information available for the development scenario to prove this statement. Opus also noted the warrant was based on the one hour count with the volumes repeated for the remaining 5 hours at 90% of the peak. They did show adding pedestrians at the location warranted a signal at Shoreline Drive under current conditions. We did a sensitivity analysis, using the same assumptions as the Bunt report and the analysis showed a signal would be warranted at Shoreline Drive when development volumes are added to the June count but not warranted with the November count (See Appendix B). This indicates signalization at this location is sensitive to the volumes used and if a higher trip generation is assumed, it could, in fact, trigger the warrant for a signal for vehicular traffic as well as pedestrian usage.

The intersection spacing is not ideal for signalization and there is potential for spillback towards Island Highway/Craigflower Road at Admirals Road intersection. However, there is only one access out of the development site as the area is surrounded by water and with the introduction of more housing units, southbound left turns will inevitably increase and cause a safety concern during the morning and afternoon peak hour. A signal would alleviate the long delays and improve pedestrian access along Island Highway. We agree with the Bunt report that if a signal is installed at Shoreline Drive, the proximity of this intersection with Island Highway/Craigflower Road at Admirals Road can be mitigated by signal coordination and adding a westbound merge lane from Shoreline Drive to approximately the location of the pedestrian bridge. With the intersection located on a horizontal and vertical curve at Shoreline Drive, advance warning signals may be required in the eastbound direction. This would be determined during the preliminary design stage.

The report mentioned the potential for a roundabout at Island Highway with Shoreline Drive Intersection. Our team reviewed this option and agree with the findings of the Bunt report that the footprint for an effective roundabout would require too much land and the substantially high volumes along Island Drive would still cause delay potential for southbound left movements.

The report also mentioned the potential for ‘half signals’. Although the report preferred full signals to half signals, Opus does not recommend installing half signals due to potential safety and operational issues.

6.2. Westbound Merge Lane at Shoreline Drive

According to the Bunt Report, a westbound merge lane is recommended along Island Highway west of Shoreline Drive for a minimum of 100 metres. This would allow the outside westbound right turn lane between Admirals Road and Shoreline Drive to become a through/right lane with more travel distance for the northbound dual left turn, southbound right and westbound through movements to merge into the westbound single through lane. The bottleneck would essentially move westward and away from the Island Highway/Craigflower Road/Admirals Road intersection. Micro-simulation modelling would be required to determine whether there would be continued spillback to the intersection of Island Highway/Craigflower Road with Admirals Road intersection.

We do agree that adding a merge lane will provide benefits to the network. The 2007 Transportation Master Plan (Bunt & Associates) recommended a westbound merge lane extending to the pedestrian bridge along Island Highway.

The length of the merge lane shown in Exhibit 2.6 (Bunt’s Christie Point TIA report) should be extended approximately 180 metres west of the intersection with an 85 metre taper to meet TAC guidelines for a 50 km/h design speed⁴ (TAC Figure 2.3.9.2 and 2.3.10.1). This length would bring it close to the location of the pedestrian bridge. Clear signage and paint markings would be required.

7. Conclusions and Recommendations

The trip generation rate was based on a one day count. As a conservative measure, we believe, a trip generation rate of 0.39 to 0.52 should be considered for this development. Due to the capacities issues already existing, modelling results will likely not change significantly by changing the trip generation rate.

Our drive and observations of the area near the proposed development showed there are capacity issues along Island Highway under current conditions and the likely reason for completing the analysis for one peak period only. However, the impact of the development increase to the morning peak hour should be considered to show that this peak hour would not significantly be impacted. The report should provide comments on the effect of the proposed development to the morning peak hour.

The new McKenzie Interchange may have an impact on the traffic volumes along Island Highway and Admirals Road. Considerations and comment of this impact should be considered in the analysis as it may affect the background traffic volumes and warrant for signalization at Shoreline Drive. If data is available, we

¹ Transportation Association of Canada, Geometric Design Guide for Canadian Roads, 1999 Edition, Part 2, Page 2.3.1.12. ² Transportation Association of Canada, Geometric Design Guide for Canadian Roads, 1999 Edition, Part 2, Page 2.3.1.17. ³ Transportation Association of Canada, Geometric Design Guide for Canadian Roads, 1999 Edition, Part 1, Page 1.2.3.3. ⁴ Transportation Association of Canada, Geometric Design Guide for Canadian Roads, 1999 Edition, Part 2.