[Council Communication]  [Siskiyou Analysis]

Council Communication

Title:	Approval of Design Elements Regarding Siskiyou Boulevard
Dept:	Public Works Department
Date:	December 18, 2001
Submitted By:	Paula Brown
Reviewed By:	Greg Scoles

Synopsis:	At the December 5th study session, staff provided the Council with a preview of several design details and an update of the design process. On December 6th, staff and the design team lead by W&H Pacific, presented this same information to various business people affected by some of the changes and also held a public Open House to hear comments and concerns regarding the overall design. At the study session, Council was alerted that a decision would be necessary on December 18th for several specific elements of the Boulevard design. Particularly, staff would need concept approval for both the Ashland Street (Hwy 66) to Walker section and the intersection of Lithia Way, E. Main and Siskiyou. The final design is on schedule. With Council's decision, the design team will continue toward final design and bring the 85-90% design to the community and Council for final acceptance in March 2002. Final design details will then be completed so that the project can go to bid in May. Construction is on schedule for mid-July 2002 and completion by December 2003.
Recommendation:	Staff recommends the following actions by Council: 1) Reject the initial concept of the roundabout at the intersection of Siskiyou / Lithia Way / E. Main and return to a more traditional signalized intersection. Direct staff to evaluate traffic circulation and bring a recommendation to Council by February on the inclusion of 3rd Street and Gresham as a part of the revisions to the intersection. 2) Accept the compromise solution (drawing to be provided at the meeting) for the Ashland Street to Walker Avenue section of the project. 3) Accept staff's recommendation to close the end of Iowa at Siskiyou with a closure detail that will be acceptable to the Fire Department and their access requirements. 4) Accept staff's recommendation to realign Beach Street, modify the current traffic signal and negotiate with the property owner for these improvements. 5) Accept W&H Pacific's recommendation to NOT include the signal at Morton Street, as it does not meet current signal warrants. The design could include the necessary undergrounding elements so that a future signal could be easily accommodated once the signal warrants are met.
Fiscal Impact:	These decisions to not impact the current funding estimate. Staff remains confident that the project will be completed within the original $2.2 million estimate. The consultant team is optimizing the need for structural repairs and asphalt overlay, and will also look to retain as much of the existing infrastructure, mostly sidewalks, yet still ensuring that all of the necessary drainage improvements and ADA requirements are met. The City has requested an additional $500,000 in OTIA funds from ODOT. To date, the Ashland "Roundabout" project is included on the recommendation project list for additional ODOT funding and expects the additional $500,000 once the Oregon Transportation Commission approves the statewide package. Staff has initialized discussions with ODOT and will modify the project prospectus to include the provisions for a signalized intersection rather than the initial project proposal for the roundabout. The need for improvements to the intersection has not changed, just the proposed solution and design.
Background:	There are two sections of the project that have not yet received concept approval; the Ashland Street to Walker section and the intersection of Lithia Way, E. Main and Siskiyou. There are also details of the project that continue to arise that staff would like Council support and approval. All of the traffic analyses and evaluations that lead to these recommendations are included in the attached memo from Transpo. Lithia Way / E. Main / Siskiyou Intersection: Initial roundabout discussions were proposed as a part of the Downtown Plan for the intersections of Lithia Way, E. Main and Siskiyou. Initial review of the roundabout option was presented to Council on September 5th as staff provided an update on all of the City's Transportation Projects. The W&H Pacific design team has reviewed the current and projected traffic volumes and presented this information to the Council on December 5th. The proposed roundabout failed to function with future traffic volumes. The option of a signalized intersection was evaluated and showed improvements to the function of the intersection if there were additional modification to the traffic on 3rd Street. Additional evaluation is needed to see how these changes impact overall traffic circulation and Gresham Street. This evaluation and a recommendation will be brought back to the Council in February. Ashland Street to Walker: The Ashland Street to Walker section of Siskiyou Boulevard has also received additional review. Reviews of traffic volumes show similar impacts for the use of either a 3 lane or a 5 lane option. The current volumes demonstrate that a 3 lane section would operate well. However, as the consultants have looked at future volumes, there is some concern that a 3 lane section might have cars backing up at the signal that could block entrances to some of the business accesses in the commercial "triangle". With that in mind, and with further discussions with the affected business owners, a compromise solution was recommended. This compromise (drawing to be provided at the meeting) includes: · bike paths on both sides - preferably 6 feet in width; a single lane in the southbound direction; a single lane in the northbound direction from Walker to Francis Lane - then continuing with two lanes northbound from Francis to the intersection with Ashland Street; a middle left turn lane (no median) throughout the section (except right at the intersection across from Omar's as described below); enhanced landscaping and some parking/loading bays on the west side of the road along the entire stretch past Omar's, and on the east side of the road in sections between Francis and Walker; a short section of raised median at the intersection of Siskiyou and Ashland Street in front of Omar's Restaurant which will act as both a pedestrian refuge and as a barrier restricting cars coming out of the northern entrance of the Omar's parking lot to a right in - right out movement (not allowing left turns at the initial driveway which is in the intersection). This detail will need to be developed further and discussed with both Omar's and SOU. Although this recommendation is a compromise, it will allow the business properties in the "triangle" to retain all of their access points and will also provide an additional lane so that the travel movements into and out of that area have additional space. That second northbound lane will also allow for additional queuing length at the signal in future years. While this solution does not fully meet the desires of some business owners who would rather have no changes at all, others see a benefit to additional parking, loading zones, landscaping and pedestrian safety elements. Closure of Iowa Street: Staff is recommending closure of Iowa Street at Siskiyou with a closure detail that will be acceptable to the Fire Department and their access requirements. This was recommended during the Otak Concept design and is being moved forward with the final design. There have been several safety items brought to the Traffic Safety Commission for consideration including this closure. Realignment of Beach Street: The realignment of Beach Street was being brought up to resolve the skewed intersection and to improve the signal operations and traffic flow. Staff has not contacted the affected property owner but is prepared to do that with Council's approval of this recommendation. Morton Street Signal: The signal at Morton Street was shown on the initial Otak Report, but was reviewed by Transpo (W&H Pacific's traffic engineering group), as it does not meet current signal warrants. Having the two signals within two blocks of each other can cause traffic flow problems and the consultant recommended that this be delayed pending the future need. Although the signal is not necessary today, the design could include the necessary electrical conduits and other undergrounding elements so that a future signal could be easily accommodated once the signal warrants are met. Open House: Staff estimates that we had over 100 people at the open house and received 20 comment sheets. Most of the verbal comments were positive. The majority of the written comments dealt with the need to fully evaluate the 3rd Street/Gresham Street decision and there were a few concerns with the closure of Iowa. Staff will have a summary available for Council at the meeting. The Boulevard Citizen Design Committee, BCDC, appointed by the mayor and council continues to serve the community well. They spend a considerable amount of time developing and shaping recommendations for the final design criteria that is used by the consulting team. Their level of input will increase as the details of the final design are now taking shape.

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Siskiyou Boulevard Traffic Operations Analysis

Introduction

The purpose of this memorandum is to summarize the results of the traffic operations review of future projects on Siskiyou Boulevard in the City of Ashland Oregon. The study area is divided into three sections: 1) Gresham Street/3rd Street/Lithia Way/East Main Intersection, 2) Siskiyou Boulevard from 4'h Street to Ashland Street (Highway 66), and 3) Siskiyou Boulevard from Wightman/Indiana Street to Walker Street. This memorandum will document the expected traffic operations resulting from changes on the street system in each of the three studysections for the present year as well as the forecast year of 2020.

Background

Siskiyou Boulevard (also known as Oregon Highway 99) is a five-lane roadway with a center turn lane and/or landscaped median, and with sidewalks along the entire project length. The project limits, between 4th (Gresham) Street and Walker Avenue, is 1.2 miles in length. There are five signalized intersections within the project limits. All other intersections are unsignalized. Siskiyou Boulevard is a major pedestrian thoroughfare that connects Southern Oregon University (SOU), Ashland High School, and Lincoln School to the Downtown area. Limited parallel parking is available on Siskiyou Boulevard, primarily on the south side in the general area of the northwestern project terminus.

The City of Ashland has received funding from the Oregon Department of Transportation (ODOT) for a modernization project for the 1.2-mile section of Siskiyou Boulevard. The project has a tentative construction start date of June 2002. As part of the improvement project, the City is assuming ownership of the project section from ODOT.

The City appointed the Siskiyou Boulevard Citizen Design Committee (BCDC) to serve as the community liaison group for public involvement and was charged with facilitating public discussion and reaching consensus on project design elements. Through a community-based visioning process sponsored by BCDC and a series of focused community workshops, an Opportunities and Constraints Analysis identified significant design considerations to guide the development and evaluation of alternative concepts. A series of design concepts were prepared and evaluated and a design section for the 4th to Walker portion of Siskiyou Boulevard was recommended to City Council. The preferred design section is documented in theSiskiyou Boulevard Design Concepts report prepared by OTAK and dated February 2001.

The preferred design concept provides recommendations for landscape and streetscape treatments in both districts including pedestrian-scale lighting for intersection crosswalks, crosswalk treatments, special street signs and streetscapes compatible with the unique character of the historic and "storefront" atmosphere of the districts. It also identifies several items in need of further analysis including.-

1. Evaluate the operations and recommend traffic flow changes to the Gresham Street, Siskiyou, Lithia Way and Main Street intersection at the fire station and library

2. Evaluate limiting University Way to a fight-out only by extending the median along Siskiyou Boulevard

3. Evaluate reducing the number of lanes from 5 to 3 on the section of Siskiyou from Ashland Street to Walker Avenue

4. Evaluate implementing a wide promenade concept in the University District through a joint effort between the City and SOU since the existing right-of- way will not accommodate the proposed width of the walkway.

This document will examine expected traffic operations of the above design concepts 1-3.

Traffic Operations Evaluation Approach

The data will primarily be quantified with the use of two transportation evaluation tools; Synchro and Vissim. Synchro is an operations model that evaluates and calculates the levd of service for coordinated systems of traffic signals. Synchro is based on methodologies consistent with the Highway ~ Manual, 2000 Edition. Synchro will be used to estimate intersection levels of service. Vissim is a microscopic traffic simulation model used to model urban traffic and public transit operations. Vissim has the capability to analyze traffic, transit and light rail operations under many different geometric and operational constraints, such as different lane configurations, traffic compositions, traffic signals, transit routes and stops. Vissim will provide a complete animated representation of existing and future operations of the transportation system, based on technical data. Vissim will also provide technical output for comparative analysis.

Gresham Street/Siskiyou/Lithia Way/East Main Intersection

This intersection was analyzed under three scenarios during the PM peak hour. The three scenarios included: 1) roundabout with existing traffic volumes, 2) roundabout with future 2020 traffic volumes, and 3) signaliTed with future 2020 traffic volumes. The roundabout option was evaluated using Vissim and the signaliTed analysis was done using Synchro. This section documents the data coded into the models as well as the results.

Existing Traffic Volumes

Typically for traffic operations analysis the peak hour traffic volume is used to provide a conservative estimate of the traffic operations during the heaviest use of a facility. The peak hour is a single hour during a typical day in which the maximum traffic volume occurs on a given facility. The peak period varies from facility to facility but is common during a PM hour that captures commuter traffic.

PM peak hour traffic volumes were used for this project to estimate the traffic operations of a roundabout and signal at this intersection. PM peak hour traffic volumes were derived from Average Daily Traffic (ADT) data provided by the City of Ashland staff. It was assumed that the PM peak hour traffic volumes represented 10 percent of the ADT.

Future 2020 Traffic Volumes

The Intersection was also evaluated under forecast 2020 traffic volume conditions. City staff provided existing traffic volumes and forecast 2019 traffic volumes at several locations along Siskiyou Boulevard. This data was used to develop an annual average growth rate, which was applied to existing traffic volumes. Based on the data provided an average annual growth rate was estimated at approximately 1 percent. To provide a conservative traffic operation analysis a 1.5 percent annual growth rate was used. The 2020 estimated volumes are also shown in Figure 1.

Roundabout Analysis

Vissim was used to estimate the traffic operations at this intersection with a roundabout used for traffic control. The analysis was performed with both existing and 2020 traffic volumes. It was assumed that all turning movements that currently use the intersection would continue to use the intersection, and that pedestrians would continue to cross the street system at similar locations and frequency as they do today. Furthermore, it was assumed that vehicles approaching the roundabout would yield to vehicles in the roundabout. The results of the analysis are shown inTable 1.

Table 1

As Table 1 shows, the Sisldyou Boulevard northbound approach is impacted the most by the expected operations of a roundabout at this location. Us'rog existing traffic volumes, the Siskiyou Boulevard is expected to have 48 seconds of delay with a queue that will vary between 175 and 730 feet depending on demand. This means that it takes a vehicle approximately 48 seconds to get from the end of the queue to entering the roundabout. The delay on Siskiyou is expected to increase to 261 seconds (4 minutes 21 seconds). This length of delay will be unacceptable with 2020 conditions.

One option was reviewed that might help the roundabout work better. Much of the delay on Siskiyou Boulevard is due to the high volume of conflicting movements coming from East Main Street (one-way) going to Lithia Way and eastbound on East Main Street (two-way). The Siskiyou Boulevard vehicles must yield to the East Main movements that are going to Lithia Way and eastbound on East Main Street. The idea is to divert the conflict'mg traffic volume that is going to Lithia Way, which are approximately 220 vehicles during?20 conditions. These vehicles would be diverted to Lithia Way via 34 Street. 3 d Street would need to be changed to two-way operation. The vehicle diversions are shown in Figure 2. The results of the traffic volume shift are shown in Table 2.

Table 2

Diverting the traffic volume between East Main and Lithia Way to 3rd Street improves the delay on Sislo/ou Boulevard from 261 seconds (4 minutes 21seconds) to 158 seconds (2 minutes 38 seconds). Although Siskiyou Boulevard'sdelay improved with the vehide diversion, East Main Street (two-way) delay increased from 17 seconds to 40 seconds. This is due to the greater volumes of traffic entering the roundabout northbound from Siskiyou providing fewer gaps for the East Main (two-way) vehides. With the traffic diversion to 3~d Street there were less conflicts in the roundabout and the northbound Siskiyou vehicles were more able to enter the roundabout, thus reducing the number of useable gaps for vehicles entering from East Main (two-way) approach.

Based on the roundabout operations analysis, a roundabout does not function well at this intersection. This is primarily due to the high north-south traffic follows, high frequency of vehicle turning movement conflicts within the roundabout, and high pedestrian activity.

Signalized Analysis

Synchro was used to analyze the intersection under signalized operation. The intersection was analyzed with future 2020 traffic volumes only. All existing turning movements were accommodated by the intersection. The turning movements and phasing are shown in Figure 3. Similar to the roundabout, a second alternative was analyzed where the volume from East Main to Lithia Way was diverted to Lithia Way via 3~a Street. This diversion allowed a signal phase to be dropped from the signal-timing plan, thus providing more green time for the heavy traffic volumes on the major streets. The signalized traffic operations are based on level of service analysis.

Signalized intersection level of service is based on the average total vehicle delay of all movements through an intersection. Vehicle delayis a method of quantifying several intangible factors, including driver discomfort, frustration, and lost travel time. Specifically, level of service criteria is stated in terms of average delay per vehicle during a specified time period (for example, the PM peak hour). Vehicle delay is a complex measure based on many variables, including signal phasing (i.e., progression of movements through the intersection), signal cycle length, and traffic volumes with respect to intersection capacity. The detailed level of service criteria is described in the Highway Capacity Manual Transportation Research Board, Special Report 209, 2000). The results of the analysis are shown in Table 3.

Table 3
East Main, Siskiyou, Lithia Way Signalized Analysis

As Table 3 shows, the intersection is expected to operate at LOS F during 2020 conditions without the traffic diversions. The intersection is expected to operate at LOS C during 2020 conditions with the East Main to Lithia Way traffic volumes diverted to 3rd Street.

Summary

It is recommended that a roundabout not be used as a traffic control tool at the intersection of East Main/Siskiyou Boulevard/Lithia Way. It is also recommended that the southbound to northbound U-Turn movement from East Main to Lithia be accommodated by converting 3rd into a two-way street. This will ensure that the future traffic signal will operate at an acceptable level of service and more importantly will simplify the intersection configuration at the couplet.

Siskiyou Median Extensions and Traffic Diversions

Traffic circulation along Siskiyou Boulevard was evaluated with the access limitations (projected median through the intersections at Union, Harrison, Liberty and Palm/University Way) with two new signals at Sherman and Morton. Also, the conversion of University Way to a right in only and the redirection of traffic as a result of this access limitation was evaluated.

This section of the memorandtun reviews three scenarios: 1) Left-turns being diverted due to median extensions, 2) University Way traffic flow revision, and 3) Iowa Street closure. The analysis was performed using the Synchro traffic operations analysis software. The baseline analysis year for this project is 2003.

Existing Traffic Volumes
Existing PM peak hour traffic volumes were based on the existing (year 2000) traffic volumes presented in the "Siskiyou Boulevard Design Concepts" report prepared by Otak, February 2001. The volumes were forecast to year 2003 by assuming an annual growth rate of 1.5 percent for 3 years in this section of Siskiyou. The traffic volumes used to establish baseline are presented in Figure 4.

Signal Timing
Existing signal timings were provided by the Oregon Department of Transportation (ODOT) for the signalized intersections along Siskiyou Boulevard. All signal timing is based on the timing plans sent by ODOT.

Future 2020 Traffic Volumes
Future 2020 traffic volumes were developed to ensure the traffic system would continue to operate well under future conditions. City staff provided existing traffic volumes and forecast 2019 traffic volumes at several locations along Siskiyou Boulevard. This data was used to develop an annual average growth rate, which was applied to existing traffic volumes. Based on the data provided an average annual growth rate was estimated at approximately 1 percem. To provide a conservative traffic operation analysis a 1.5 percent annual growth rate was used to develop future traffic volumes.

Left-Turn Diversions
The left-tum diversion analysis assumes that the Siskiyou Boulevard median will be extended through the intersections of Union, Harrison, Liberty and University. The traffic will be diverted to the signalized intersections of Sherman, Morton, Beach, and Mountain. The volume diversions can be seen graphically in Figure 5.

The left-turning traffic at Union is expected to move to Sherman. The net traffic volume at Sherman is expected to increase by 20 mph. The northbound left-turn increases by 20 mph and 20 vehides that used to go through Sherman to access Union will now turn left at Sherman.

It was assumed that the left-tums from Harrison and Liberty would divert to Morton. Morton would experience approximately 95 new trips per hour. The north-to-west left-turn on Morton would increase from 15 mph to 50 mph and the west-to-south left-turns would increase from 30 mph to 120 mph. The westbound through trips would decrease by 30 mph. No new trips were assigned to Beach/Morse.

The left turn trips from University Way were assigned to Mountain. At Mountain, the north-to-west left-turn is expected to increase from 140 to 165 mph, and the northbound through trips are expected to increase from 40 to 45 mph. The south-to-eastbound trips are expected to increase from 85 to 90 mph. The east-to-north left-turns are expected to increase from 60 to 80 mph and the eastbound through trips are expected to decrease by 20 trips. The westbound through trips are expected to decrease by 25 mph. This is a net increase of 10 mph to the intersection. Most vehides that once traveled through the intersection are now turning at the intersection of Mountain.

Left-turn Diversions Operations Analysis
The left-turn diversion impacts to the signalized intersections were analyzed using the Synchro software. The impacts to the four signalized intersections with increased traffic volumes are shown in Table 4, as well as the expected condition in the year 2020.

Table 4
Left Turn Diversion Operations

As Table 4 shows, the shifts in traffic volume due to the median extensions is not expected to degrade the level of service at the signalized intersections. The results of this analysis are reasonable since the vehicle volumes being shifted are relatively small. The analysis also indicates that the signalized intersections are expected to operate well under 2020 conditions.

University Way Right In Only
Under this scenario it was assumed that the traffic flow on University would be reversed from one-way outbound flow to one-way inbound flow onto Siskiyou Boulevard. The outbound traffic on University was shifted to Mountain, and half of the existing southbound right-tums at Mountain were shifted to University. This scenario also assumes the median extension at University exist such that those lefts are diverted to Mountain, as was the case in the previous scenario.

As shown in Figure 5, the outbound traffic volumes were already shifted to Mountain due to the median extensions. Thus, the only outbound volume shifted to reverse flow on University Way was the 60 right out vehides.

University Way Right In Only Operations Analysis
Shifting the flow of traffic on University will primarily impact Mountain Avenue because most of the traffic will divert to Mountain. University Way is expected to operate well because with the median extension traffic flow will be right in only at University. The expected impacts of shifting more traffic from University to Mountain were evaluated with Synchro. The results of the analysis are shown in Table 5.

Table 5
University Traffic Flow Reversed

As Table 5 shows, shifting the additional traffic to Mountain from University to accommodate the change in traffic flow is not expected to degrade the level of service at Mountain. Based on the 2020 analysis, Mountain is expected to continue to operate at an acceptable level of service.

Iowa Closed
This scenario assumes that Iowa Street is dosed at the location where it intersects Siskiyou Boulevard and Beach/Morse Street. The traffic approaching Siskiyou/Beach/Morse was rerouted to Morton Street. Thus, at Morton Street the northbound left-turn was increased by 20 mph; the through trips were increased by 20 mph; and the right-tums were increased by 70 mph. The analysis also assumes the same traffic diversions that were used for the median extension, assuming Iowa would be closed as well as the median extension project.

Iowa Closed Operations Analysis
Closing Iowa Street will impact Siskiyou Boulevard at the intersections of Morton and Beach/Morse. The expected impacts of shifting more traffic from Iowa to Morton and closing Iowa at Beach/Morse were evaluated with Synchro. The results of the analysis are shown in Table 6.

Table 6
Iowa Closed

Table 6 shows, both intersections will continue to operate well if Iowa Street is closed. Morton is expected to continue to operate at LOS A. And Morse/Beach is expected to increase from LOS B to LOS A. Morse/Beach improves because one less signal phase is required at this intersection when Iowa is closed. Thus, more green time is available to process vehicles at the remaining approaches. As Table 6 shows, both of these intersections are expected to operate well with forecast 2020 traffic volumes

Summary
As the traffic operations analysis in this section shows, extending medians, closing streets, and reversing traffic flow on University is not expected to degrade the level of service at the signalized intersections on Sisldyou Boulevard between Union and University. This is primarily due to the low traffic volumes on the side streets that are impacted by the infrastructure adjustments. Shifting these low volumes to the signalized intersections is not expected to significantly increase delays or queues at the signalized intersections analyzed. Furthermore, with the proposed changes, the intersections are expected to continue to operate well in the forecast year of 2020.

Siskiyou Boulevard - Hwy 66 to Walker (5 vs. 3-Lanes)

This section of the memorandum documents the analysis of Siskiyou Boulevard from Indiana/Wightman to Walker Avenue. The traffic operations analysis consisted of evaluating existing and future (2020) traffic volumes and circulation of two street system altematives. The alternatives analyzed include the existing system with 5-Lanes (Existing 5-Lane) and an alternative concept with 3-Lanes (Future 3-Lane Option) between Highway 66 and Walker Avenue. The traffic analysis was performed using micro-simulation (Vissim).

As discussed earlier, Vissim is capable of accounting for the interaction of every vehicle within a network Thus, Vissim will provide detailed information of vehicle impacts to up/downstream intersections and driveways.

Baseline (2003) Traffic Volume Test
This section of the report documents the results of the 5-Lane and the 3-Lane option traffic operations using baseline (2003) volumes. The same traffic volumes were used for each option. However, the signal timing data was adjusted for the 3-Lane option to account for the geometric reductions in capacity as well as for some turning movement adjustments at Siskiyou Boulevard/Highway 66. In addition the 5-Lane option included a single south to east left turn lane as exists today, while the 3-Lane option was evaluated with two south to east left lanes. The two left turn lanes were added to accommodate the heavy vehicular demand for this movement and to improve the overall operation of the intersection.

Traffic Volumes
Existing traffic volumes were based on the turning movement counts provided in the Siskiyou Boulevard Design Concepts" report prepared by Otak, February 2001. The volumes were forecast to year 2003 by assuming an annual growth rate of 1.5 percent for 3 years. The PM peak volumes are shown in Figure 6.

Signal Timing
Existing signal timing information was provide by the Oregon Department of Transportation (ODOT) for the Siskiyou Boulevard. All existing signal timing, for the 5-Lane, is based on the timing plans sent by ODOT. Signal timing was appropriately adjusted for the modifications made to the 3-Lane Option. For the 3-Lane option the signal-timing plan at Siskiyou Boulevard/Highway 66 and Siskiyou Boulevard/Walker Avenue had to be adjusted to account for the reduction in roadway capacity (i.e., the reduction in travel lanes). Also, at Siskiyou Boulevard/Highway 66 a left-turn from Highway 66 to southbound Siskiyou was included to provide maximum traffic circulation capability and to avoid cut through traffic through private properties. Signal timing is provided in the appendix.

Simulation Results
The existing traffic volumes, signal timing, and appropriate intersection geometry were coded into Vissim. Data was collected for both the 5-Lane option and the 3-Lane option. Queue data was collected at all approaches at Siskiyou Boulevard/Highway 66 and travel times were collected on a segment of Siskiyou Boulevard and Highway 66. The three travel times collected are:

1) Siskiyou southbound, beginning north of Wightman St./Indiana St. and  ending south of Walker Ave.

2) Siskiyou northbound, beginning south of Walker Ave and ending north of Wightman St./Indiana St.

3) Highway 66 westbound, beginning east of Siskiyou Boulevard and ending  north of W~ghtxnan St./Indiana St.

The purpose of the data collection is to measure the degree of change between the different lane configuration options and volumes. Table 7 provides the results of the queuing data collected at Siskiyou Boulevard/Highway 66. Southbound queue measurement includes vehicles traveling through the intersection on Siskiyou and turning left on to Highway 66. Northbound travel times include vehicles traveling north through the Siskiyou/Highway 66 intersection; and westbound includes vehicles traveling from Highway 66 turning onto Siskiyou.

Table 7
Siskiyou/Hwy 66 Queue Comparisons (2003)

As Table 7 shows, the southbound queues are reduced due to the added left-tum capacity provided by the dual-left from Siskiyou to Highway 66. The northbound left is expected to increase due to the reduction in lane capacity, and the westbound approach is expected to operate similar under both the 5-lane and 3-lane option The northbound queues could be mitigated by adding a second though lane in the northbound direction. Table 8 provides the results of the travel time analysis.

Table 8
Siskiyou Travel Time Comparison (2003)

As Table 8 shows, the time to travel on Siskiyou between Wightman/Indiana and Walker is expected to increase by approximately 10 seconds in each direction. The increase of 10 seconds will probably not be discemable by most drivers due to the fact that it is spread out over three intersections. Travel time from Highway 66-to-Siskiyou should remain relatively consistent. Based on 2003 traffic volumes the 5-Lane and 3-Lane concepts are expected to operate similar. The 3-Lane option improves the south-to-east left turn at Siskiyou/Highway 66, and slightly degrades the westbound operations. This is mainly due to converting one of thesouthbound through lanes in the 5-Lane option to a left turn lane in the 3-Lane option.

Future 2020 Traffic Volume Test
This section of the report documents the results of traffic impacts to the street system when traffic volumes increase over the next 17-years, from 2003 to 2020. Traffic volumes were increased at an annual growth rate of 1.5 percent for 17 years and the signal timing was recoded for both the 5-Lane and 3-Lane options to account for the increase in traffic demand.

Future 2020 simulation results
The following two tables document the expected impacts to the 5-Lane and 3-Lane options due to increased traffic volumes over a 17-year period. Table 9 shows the impacts to traffic queues at Siskiyou/Highway 66 for 2020 compared to the 2003 conditions.

Table 9
Siskiyou/Hwy 66 Existing vs. 2020 Expected Queues

The approximate distance between the Highway 66 intersection and Wightman/Indiana is 220 feet. As Table 9 shows, the average queue should be less than 220 feet under all scenarios for the southbound direction. The maximum queue is expected to extend through the Wightman/Indiana intersection a few times every PM peak period. The average eastbound queues are not significant considering the average is 200 feet, which is approximately equivalent to 10 vehicles (assuming average of 20 feet per vehicle). However, due to the close proximity of W',ghtman/Indiana the queue becomes more significant due to it impacts of pedestrian and vehide traffic at Wightman/Indiana. The northbound and westbound queues are both expected to increase slightly in 2020. The impacts of increased traffic volume on travel time are shown in Table 10.

Table 10
Siskiyou Travel Time ( seconds) Comparison

As Table 10 shows, future 2020 traffic volumes are not expected to significantly impact travel times through the study area. This is primarily due to the adjustments made to the signal timing and the added south to east second left turn.

The conversion of Siskiyou Boulevard from a 5-Lane to 3-Lane section between Highway 66 and Walker does not negatively impact traffic operations along this roadway segment. The analysis showed that minor congestion occurs on Siskiyou Boulevard between Indiana and Highway 66. The 3-Lane option provides enough capacity bebveen Highway 66 and Walker.

It is important to note that the current 5-Lane section between Highway 66 and Walker does not accommodate business deliveries in a safe and effident manner since delivery trucks park in the two-way-left-mm-lane and cross two lanes of traffic. The 3-Lane option provides an opportunity to add outside parking lane and bicycle lanes on both sides of the street. The following recommendations are proposed:

1. Convert the existing 5-Lane section into a 3-Lane section between Highway 66 and Walker. The 3-Lane section should be configured with parking and bicycle lanes on both sides of the Siskiyou and a potential second northbound pocket at Highway 66.

2. At the intersection of Highway 66 and Siskiyou Boulevard, add a second south to east left turn pocket by converting one of the existing southbound through lanes.

3. Add a west to south left turn lane by converting the existing two-way-left-

4. Modify the traffic signal at Highway 66 and Siskiyou to accommodate the above recommendations.

5. Optimize the traffic signal timing plans at Highway 66 and Indiana  intersections

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