TIA Addendum No. 1 – Helmcken Rd. / Watkiss Way Intersection

MEMORANDUM

Date: September 29, 2023 To: Ivan Leung, P.Eng., Town of View Royal Cc: Vasile Dumitru, AScT, WestUrban Developments LTD. From: Andy Kading, P.Eng., WATT Consulting Group Our File No: 2755.B01 Subject: TIA Addendum No. 1 – Helmcken Rd. / Watkiss Way Intersection

INTRODUCTION

WATT Consulting Group was retained by WestUrban and the Town of View Royal to complete an addendum in response to comments regarding an earlier Traffic Impact Assessment (TIA) completed on August 17, 2023¹. The TIA provided an assessment in support of a proposed development located at 9 Erskine Lane, in the Town of View Royal.

The objective of this addendum is to provide context on the impact of different intersection control options at the intersection of Watkiss Way / Erskine Lane on the traffic operations at the intersection of Helmcken Roady / Watkiss Way. All analysis and recommendations presented in this Memo are complementary to the original TIA document.

EXISTING CONDITIONS

According to analysis presented in the TIA (see Table 1), the intersection of Helmcken Road / Watkiss Way currently operates as a signalized intersection, with LOS E and F experienced by select movements during both the AM and PM peak hours. Consistent with current traffic control, the intersection of Watkiss Way / Erskine Lane was modeled as a stop-controlled intersection, which provides an acceptable LOS A on all movements.

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¹ 9 Erskine Lane TIA, August 17, 2023, WATT Consulting Group

Table 1: Existing Traffic Operating Conditions

Constrained geometry at Helmcken Road / Watkiss Way has resulted in a long cycle length with split phasing for northbound traffic, which sacrifices (in the form of increased delay) the minor Chancellor Way in favor of predominant east / west through movements along Helmcken Road. Of note is the low v/c ratio for the northbound and southbound (Watkiss Way / Chancellor Way) left turning movements which demonstrates that although these movements perform poorly in terms of delay, the total amount of traffic they serve is relatively low compared to Helmcken Road volumes.

IMPACT OF TRAFFIC CONTROL SELECTION IN FUTURE HORIZONS

In the post development opening day (2023) and future (2033) scenarios, northbound and southbound left turning traffic at the intersection of Helmcken Road / Watkiss Way is anticipated to experience a decrease in LOS (i.e. increased delay) as presented in Table 2 and Table 3. However, similar to the existing conditions, low v/c ratios indicate that these movements support lower traffic volumes and on their own do not trigger any intersection improvements.

Table 2: 2023 Traffic Operating Conditions

Table 3: 2033 Traffic Operating Conditions

Further to recent discussions with the Town of View Royal, it is understood that various traffic control options are being explored for the intersection of Watkiss Way / Erskine Lane, including a roundabout and traffic signal alternative.

As shown in Table 2 and Table 3 the Watkiss Way / Erskine Lane performs at LOS A with stop-control. The Town of View Royal is exploring other traffic control options for the intersection including a roundabout and a traffic signal. From a traffic operations perspective, both the roundabout and traffic signal provide perform at LOS A for all approaches in both the 2023 and 2033 post development scenarios (Table 4 and Table 5). However, it is of interest to consider any potential impacts to the downstream intersections.

Table 4: Traffic Control Options – 2023

Table 5: Traffic Control Options – 2033

It is noted that the type of intersection control selected for any given location has direct influence on the LOS experienced at that intersection alone. The operating conditions of upstream and downstream intersections are driven by the flow of traffic into/out of those intersection, and not the preceding intersection’s form of traffic control (except in highly congested corridors where queuing is present, which is not the case here). In other words, the operational performance of the Helmcken Road / Watkiss Way intersection is not influenced by the traffic control at Watkiss Way / Erskine Lane or vice versa.

Operating conditions presented in Table 4 and Table 5 indicate that there are no operational concerns for the post development horizon for the intersection Watkiss Way / Erskine Lane with the existing stop control, a roundabout, or traffic signal will result in identical operating conditions for the downstream intersection of Helmcken Road / Watkiss Way.

CONCLUSION & RECOMMENDATIONS

Based on the analysis presented in the TIA and this addendum, it is expected that the intersection of Watkiss Way / Erskine Lane will operate at LOS A for all movements in both the 2023 opening day and 2033 future horizon, regardless of the intersection control selection (stop control, roundabout, signal), with all movements experiencing minimal delay.

Considering that there are no queuing concerns noted for either Watkiss Way / Erskine Lane, or for the Watkiss leg of the Helmcken Road / Watkiss Way intersection back to Erskine Lane, it is expected that the downstream intersection of Helmcken Road / Watkiss Way will experience the exact same operating conditions regardless of the traffic control type selected at Watkiss Way / Erskine Lane. Therefore, all results in the previously submitted TIA are the same regardless of the intersection control at Watkiss Way / Erskine Lane.

We trust this memo provides the information of interest. Please feel free to reach out to me directly if you have any questions or require more information.

Sincerely,

WATT Consulting Group

Andy Kading, P.Eng. Transportation Engineer C 236-464-3263 E akading@wattconsultinggroup.com