review of the parking and traffic study for park cities ymca redevelopment

7/31/2019 Review of the Parking and Traffic Study for Park Cities YMCA Redevelopment

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Review of the Parking and Traffic Study for

Park Cities YMCA Redevelopment

Prepared for:

University Park, Texas

August 23, 2012

Prepared by:

KEVIN ST.JACQUES,P.E.,PTOE,PTPFREESE AND NICHOLS,INC.1701 N Market St, #500, LB51

Dallas, Texas 75202214-217-2200

CUP12336


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CONTENTS

Page

Executive Summary 1

1. Assessing the Study Methodology 4

2. Assessing the Existing Conditions Baseline and Its Analysis 5

3. Assessing the Future Conditions Estimate and Its Analysis 14

4. Assessing the Identified Impacts, Issues and Recommended Mitigation 19

5. Other Considerations 22


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Executive Summary

Freese and Nichols, Inc. was retained by the City of University Park to review the Parking and

Traffic Study for Park Cities YMCA (PC YMCA) Redevelopment in University Park and its

associated Memoranda prepared by DeShazo Group, Inc. (DeShazo). The following is a

summary of our findings.

1. Assessing the Study Methodology.

a. The DeShazo extrapolation of the existing usage, traffic and parking patterns onto that

of the future building uses is a very strong methodology for estimating future parking

needs and traffic activity.

b. Careful documentation of existing parking and traffic conditions and correlation to the

existing facility activities is essential to the methodology and DeShazo has done this

reasonably well.

2. Assessing the Existing Conditions Baseline and Its Analysis.a. Numerous assumptions were made to identify the proper baseline of traffic and parking

characteristics for projection onto the proposed expanded facility, introducing a margin

of error with each assumption.

b. The 1.26 factor increases the parking and traffic observations on a typical day to

represent a comparatively high estimate of a busy day at the PC YMCA.

c. Collection of data on a Thursday rather than either a Monday or Wednesday appears to

have under estimated the average PM peak weekday activity of the PC YMCA in the

baseline data by as much as 20%, and the duration of the AM peak period is a bit longer

on Monday/Wednesday than on Tuesday/Thursday.

d. Reassessment of the baseline PM peak hour traffic does not change the roadway traffic

operations Level of Service. However, the demand for the parking during the weekday

morning would stay at peak level for at least one hour longer and the weekday

afternoon parking demand would be greater by about 18 spaces.

e. The parking counts were taken on both sides of the streets immediately adjacent to the

PC YMCA and attempted to count PC YMCA parking activity on Shenandoah and

Normandy west of Preston Road and Normandy east of Connerly. But, due to the

significant under-supply of parking at the PC YMCA, it is expected that PC YMCA parking

occurs beyond the data collection area at time of peak usage. So, a 5% increase in the

baseline parking demand (8 spaces in the AM, 6 spaces in the PM) is recommended.

3. Assessing the Future Conditions Estimate and Its Analysis.a. The DeShazo Study assumes that the new gym, Rise School and therapy pool are the

only new traffic and parking that will be generated at the PC YMCA.

b. Closer examination of future uses over those considered in the baseline parking and

traffic formulation suggests the following additional elements of the PC YMCA space

programming:


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o No additional spaces are in the programming for additional parking for the

increased Office space. It is recommended that this be increased by 3 spaces.

o 22 spaces are in the programming for additional parking for the Rise School. It is

recommended that this be increased by 5 spaces to account for closer spacing

and longer duration of drop-off and pick-up parking activity.

o 95 spaces are in the programming for additional parking for the Gymnasium. It isrecommended that this be increased by 36 spaces due to a higher vehicle to

team member ratio.


increased Multipurpose space. It is recommended that this be increased by 10

spaces due to the increase in the number and size of spaces and potential

classes.


increased Adult Fitness and Spin Area space. It is recommended that this be

increased by 5 spaces due to the increase in the size of the space and potential

densification.

c. The resulting parking assessment increases the peak parking demand on a very busy day

at the PC YMCA to about 330 spaces, 71 more than the 259 in the DeShazo report.

d. The resulting increase in traffic activity still results in nearly free flow (Level of Service A

or B) traffic operations on Preston Road, while the side streets of Normandy and

Shenandoah operate at acceptable (LOS C, D or E) peak period traffic operations. The

impact on the nearby arterial street system is negligible due to the relatively low volume

of PC YMCA traffic compared to that on Preston, Mockingbird and University.

4. Assessing the Identified Impacts, Issues and Recommended Mitigation. These include:

a. The existing offset intersection of Normandy at Preston should be addressed to

eliminate the offset, since increased focus of activity at this intersection will increase thepotential for crashes in its offset configuration. The safety of the existing offset

intersection, if retained, can be enhanced by separating the green time for the

westbound and eastbound Normandy movements (splitting the phases). Alternatively,

the realignment to eliminate the offset could be done, which may facilitate

configuration to eliminate the through traffic movement on Normandy. In either

condition, the pedestrian crossing at the intersection should be enhanced.

b. Queue lengths at exiting the parking garage during the peak hours are anticipated to be

typically about 100 feet in length to as much as 129 feet. This length of queue would

interfere with the efficient operation of the exit ramp from the garage, which is

programmed at 75 feet from the intersection. The exit driveway from the garage shouldbe positioned 125 to 200 feet from the intersection.

c. Parking accommodations on Shenandoah and Connerly east of Preston should be

restricted to neighborhood parking only, to force utilization of the parking garage and

mitigate the need to circulate through the neighborhood looking for parking. The 15

spaces on Normandy at the church should be restricted to non-PC YMCA usage except

for handicap and certain designees.


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Introduction

Freese and Nichols was retained by the City of University Park to review the Parking and Traffic

Study for the Park Cities YMCA Redevelopment in University Park and its associated

Memoranda, developed by DeShazo Group, Inc. (DeShazo) for the Park Cities YMCA (PC YMCA).

The DeShazo study report is dated March 15, 2012. Supplementary information was developedin various Memoranda: (3/20/12) commentary on review of Normandy Lane Traffic Diverter

prepared by Lee Engineering on behalf of a resident group, (3/20/12) commentary on the

addition of a Rise School to the PC YMCA Redevelopment, and (4/25/12, updated 5/1/12)

supplement to the Traffic Impact Analysis to encompass additional intersections.

1. Assessing the Study Methodology

The goal of a traffic impact study is to assess potential impacts of traffic changes caused by

proposed development on municipal roads and to identify any infrastructure improvements or

mitigation measures needed to ensure the road network will operate acceptably and safelyupon completion of the proposed development. The Institute of Transportation Engineers (ITE)

publishes a Recommended Practice for Traffic Impact Studies, which DeShazo will have

followed. The steps to conducting a traffic impact study include the following:

a. Identify the specific development plan under study and any existing development on

and/or approved plans for the site as well as any known changes on property abutting

the proposed development site, including property across public streets.

b. Identify the ultimate arterial and collector street network in the vicinity of the site.

c. Document current public street characteristics adjacent to the site, including the

nearest arterial and collector streets.

d. Estimate the number of trips generated by existing and proposed development on the

site for a typical weekday and weekday peak hours using the latest edition of Trip

Generation published by the Institute of Transportation Engineers. Local trip generation

characteristics may be used, and are preferred, if deemed to be properly collected and

consistent with the proposed development.

e. Document current peak hour traffic volumes on a typical weekday (Tuesday,

Wednesday, and/or Thursday). The time periods in which existing traffic is counted

should generally coincide with the highest combination of existing traffic plus traffic

expected to be generated by the proposed development.

f. Estimate future PM peak hour traffic volumes for the intersections included in the study

area using either ITE Trip Generation values for similar development types or,

preferably, the trip generation characteristics of the existing or a nearby similar site.g. Distribute and assign the net development trips through the site driveway(s) plus the

nearest collector/arterial street intersections in each direction along streets bordering

the development site.

h. Conduct volume/capacity analyses for the peak hours at site driveway(s) and other

intersections using methodologies outlined in the latest edition of the Highway Capacity

Manual published by the Transportation Research Board. The analyses should be


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conducted for 1) existing conditions, 2) existing plus development conditions, and 3)

future conditions.

i. Identify geometric and traffic control improvements needed to mitigate deficiencies

and/or comply with established guidelines/policies.

Similarly for assessment of parking needs, standardized parking ratios, such as those in theCitys Ordinances, can be used to determine the parking requirement. However, a more

accurate estimate of the parking needs of the proposed facility would utilize parking

observations at an existing or nearby similar site to project.

The methodology chosen by DeShazo was to use the characteristics of the existing PC YMCA to

estimate the parking and traffic conditions for the proposed PC YMCA redevelopment. This

approach is the most appropriate among the options available. The re-developed PC YMCA will

most closely compare to the characteristics of the existing PC YMCA operations, with select

additional activities.

2. Assessing the Existing Conditions Baseline and Its Analysis

Using the existing conditions to predict future parking and traffic operations requires careful

documentation of the existing parking and traffic characteristics and correlating them to the

activities in the existing facility. Additionally, numerous assumptions needed to be made to

identify the proper baseline of traffic and parking characteristics for projection onto the

proposed expanded facility.

Existing Parking Counts

DeShazo conducted parking accumulation counts along both sides of Preston,

Shenandoah, Connerly, and Normandy adjacent to the PC YMCA, andattempted to count PC YMCA patrons that parked on Normandy and

Shenandoah Avenues west of Preston Road and on Normandy Avenue east of

Connerly. It is likely that there were other PC YMCA parking activities beyond

their data collection zone, though would not be expected to be more than a

few cars, so a 5 percent adjustment factor should be added to the peak

values concluded from the data. The baseline AM and PM peak parking

demand should be increased by about 8 spaces and 6 spaces, respectively.

Card Swipe Historical Usage Data

The PC YMCA requires members to swipe their membership card past their card reader uponentry to the facility each time they arrive. Historical card swipe usage data was made

available to DeShazo for use in the study. Notably, the youth members do not swipe cards, only

the adults, so the card swipes are a good indicator of automobiles parking at the site.

However, for the field sports as well as the Pre-K, the comings and goings of those cars parking

at the site are not included in the card swipe data. They would, however have been counted in

the traffic volumes and parking data.

Due to limitedcapture area of the

parking counts, a 5%

adjustment factor

should be added to

the baseline

conditions total.


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Selection of 2010 as Base Year

A review of the annual summaries of the card swipes beginning in 2003 (see Figure 1) shows

that the data for 2010 was a good data set for use as it represents the second highest activity

level for the PC YMCA for the last 10 years. (Surrogate data was used to complete missingmonths in the 2011 and 2012 data.)

Monthly Variation of PC YMCA ActivityLikewise, the card swipe data varies by month of year, as shown in Figure 2. The general

trend of the data indicates that facility usage gradually decreases throughout the year. This

trend was verified by PC YMCA. Notably, the 2010 data shows the highest January in 10 years.

2010

Figure 1. Annual Variation in Card Swipes at PC YMCA


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Seasonal Adjustment Factor

The DeShazo study developed a factor to adjust the data collected in October and November to

represent an activity level to use as the baseline for analysis. They chose to grow the parking

and site traffic of the actual data collected to approximately represent the highest card swipe

activity day of the year. This adjustment factor is a ratio of the weekly card swipes for the firstweek in November to the highest week of card swipes of the year, as graphically represented in

Figure 3. The 1.26 factor multiplies the parking and traffic observations on a typical day to

represent an estimate of a very busy day at the PC YMCA.

The 1.26 adjustment factor is a comparatively high estimate for growing the activities

represented by the card swipes to determine the baseline condition. The factor 1.26 is a ratio of

daily activity levels, but much of the increase in the higher activity days in January through

March may be due to middle of the day activities, whereas the 1.26 growth factor will be

applied to the entire day and most notably to the peak hour activities. The adjustment factorwould also be an overestimate of the growth in Pre-K activity as well as staffing. The DeShazo

report identified that the 1.26 factor is not applied to the field sports activity but rather is

considered the field sports activity separately from the rest, which is appropriate and facilitates

comparisons.

Figure 3. Weekly Variation in Card Swipes at PC YMCA and Adjustment Factor


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Day of Week Variation

The parking occupancy counts and the traffic counts were both collected on Thursdays.

Collection of data on a Thursday rather than either a Monday or Wednesday results in an

average weekday inconsistent with the conservative approach used for the site traffic andparking. Specifically, as depicted in Figure 4, the afternoon peak period appears to be under

represented in the baseline data by about 20%. The morning peak, though not much higher on

Monday/Wednesday than Tuesday/Thursday, appears to last longer and thus could be

expected to impact parking occupancy.

Figure 4. Hourly Variation in Card Swipes for Monday vs Thursday


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Baseline Parking

DeShazo physically counted the occupied parking spaces on both sides of Preston, Shenandoah,

Connerly and Normandy adjacent to the site on Thursday, November 4, 2010. The DeShazo

study assumed that all parking on these four street segments is attributed to the PC YMCA. The

study attempts to draw inferences from parking activity in selected areas within one block fromthe site, but indicates that the results are estimates at best. Parking for the PC YMCA that may

occur beyond this parking study zone are not considered.

Parking Attributed to Youth Field Sports

The PC YMCA has confirmed that on the parking data collection date, November 4, there were

scheduled soccer games in the soccer field at 4:30 and 5:30 p.m. The DeShazo report estimated

a portion of the observed afternoon parking to be from the soccer games. During the period

between 4:00 and 5:00 p.m. that day, sports parking demand reached the full amount needed

for both games, and was estimated at 40 parking spaces. Thus, an estimate of the parking

demand for one game is about 20 spaces. Using the YMCA-provided average youth soccer teamsize of 8 youth, the average parking demand rate for youth soccer can be estimated at 1.25

spaces per team member. However, it is likely that the parking occupancy counts did not

include some of the shorter duration parking activity or did not capture the full extent of where

parking occurs for the sports field activities. There also may have been more or less than 8

youth in attendance at the games on the day of data collection. A factor of 1.5 parked cars per

team member would be appropriate for assessment of the redevelopment.

Figure 5. DeShazo Parking Occupancy Observations at PC YMCA on November 4, 2010


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Adjustment of Parking Count Data

In the DeShazo report, the parking occupancy counts made in early November were grown by

the seasonal factor of 1.26, but with the field sports parking separated out and handled

separately. This approach to growing the youth sports program parking separately is logical.

Consideration of the daily variation that was depicted in Figure 4, the parking data could be

further grown to reflect the busier Monday/Wednesday schedule. The resulting modified

baseline parking demand would be as depicted in Figure 7. An increase of 18 additional parking

spaces in the PM peak period are recommended in the baseline.

Figure 6. DeShazo Baseline Parking Demand at PC YMCA, without field sports

Figure 7. Modified Baseline Parking Demand at PC YMCA, without field sports


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The baseline plus field sports parking would then be depicted as shown in Figure 8. As shown in

the figure, the evening peak parking demand approaches that of the morning peak parking

demand. The DeShazo report indicated that the baseline AM peak parking demand is

approximately 196 spaces and the PM peak is approximately 135 spaces, without the youth

sports added. With consideration of a Day-of-Week adjustment, the PM peak baseline parking

needs would increase by about 18 spaces, for a total of 153 in the PM peak period, againwithout the youth sports. Adding in the 5% adjustment factor for the limited parking data

capture area, described previously, the new baseline total for parking demand becomes 204 in

the AM peak and 159 plus youth sports in the PM peak.

Baseline Traffic Operations

The influence area of the PC YMCA on traffic operations is considered to extend:

a. Southward along Preston Road to the Mockingbird intersection and encompassing the

signalized intersections with Normandy Avenue and St. Andrews Drive and the un-

signalized intersection of San Carlos (Potomac is one-way eastbound so would have

limited use as an accessway and is not considered for impact analysis);

b. Northward along Preston Road to the University Boulevard

intersection and encompassing the un-signalized intersection

of Shenandoah. Notably, the signalized intersection of McFarlin

Boulevard and the un-signalized intersections of Stanhope

Street, Windsor Park and Windsor Avenue;

c. Due to the configuration of the PC YMCA site, the local street

intersections of Connerly Drive at Normandy and Shenandoah

Figure 8. Suggested Modified Baseline Parking Demand at PC YMCA, with field sports


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Avenues are involved in the circulation pattern at the site and are included in the

analysis.

d. The analysis considers the traffic impacts of site traffic on the intersections of

Shenandoah, Normandy and San Carlos with Douglas Avenue, a collector roadway 800

feet west of Preston Road.

The existing conditions traffic operations were modeled by DeShazo using Synchro, a trafficanalysis software commonly used in traffic impact studies. Traffic volumes and signal attributes

were properly input into Synchro. Notable findings of the DeShazo analysis include:

a. The existing intersection of Preston at Normandy operates at Level of

Service A, an overall very good traffic flow. The signal operation is

actuated with the resting green indication set for Preston Road

creating a free flow condition for Preston Road until a side street call

for green is detected. The Preston Road movements are the

predominant movement (1,227 in AM and 1,659 in PM) and operate at

LOS A, heavily weighting the average for the intersection. The

Normandy side street is the minor street (either the west or east

approach is about 5% that of Preston Road) and operates at LOS D/E as

it rarely justifies more than the minimum green time. The existing cycle length of the

traffic signal is 120 seconds, consistent with TxDOT potential coordination of the

Preston Road signals. The DeShazo study indicates that the signal could be operated

with shorter cycle lengths, allowing the side street green to occur more frequently

though still at minimum duration, and retain the LOS A for the intersection while

improving the operations for Normandy to LOS B.

b. The existing un-signalized intersection of Preston at Shenandoah

operates at Level of Service A, an overall very good traffic flow, again

predominantly due to the free flow conditions for the much larger

traffic volumes on Preston Road. The westbound traffic onShenandoah operates at LOS D in both the AM and PM peak hours.

c. The intersections of Preston Road at Mockingbird Lane and University

Boulevard both operate at LOS C. Notably, the southbound Preston

Road queue lengths are over 200 feet in length, potentially

encouraging traffic wanting to continue to the west on Mockingbird to

divert through the neighborhood west of Preston Road.

d. Notably, only one soccer game, at 4:30 p.m., was held on October 28, 2010, the day of

the traffic data collection, rather than the two back-to-back games as was held during

data collection for the parking occupancy counts. Thus, another 20 cars should be

distributed to ingress and egress the site during the PM peak hour.

Traffic Variations

The baseline traffic counts were gathered on Thursday, October 28, 2010. As noted previously,

the year 2010 is a relatively high base year to use for projecting existing traffic operations onto

the future facility traffic operations. Within the year, traffic volumes tend to vary seasonally, by

month and even from one week to the next.


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Annual Average Daily Traffic Counts (AADT) are collected by Texas Department of

Transportation (TxDOT) on major highways and regionally significant arterials. The counts are

done during the non-summer weeks; excluding Fridays, Saturdays, Sundays, and holidays. The

AADT counts are what could be expected during a normal workday of a given week. Monthly

variation factors compiled by TxDOT indicate that data collected during October are at orslightly above the average workweek for the year. Traffic counts taken on a Tuesday,

Wednesday or Thursday are generally considered to be typical for the local weekday traffic.

However, as the PC YMCA schedule of programs is busier on Monday/Wednesday

than on Tuesday/Thursday, an increase in the site generated PM Peak Hour in

and out traffic of approximately 20% plus an additional 20 cars arriving and

departing during the PM peak hour for a second soccer game, is recommended to

be considered for the baseline traffic volumes. The Synchro models developed by

DeShazo were received for use in reassessing the traffic operations, and were

reviewed for accuracy of representation. Increasing the PM peak hour site volumes has little

impact on intersection performance on Preston Road. The new level of service performance

measures, after reallocation of a few seconds of green time to the Normandy approach, are the

same as before the volumes increase, as shown in Figure 9. The reason that the network

absorbs these minor increases in traffic is due to the current very low delay incurred by the

Preston Road through traffic at the Normandy intersection. Beyond the Normandy intersection,

the PC YMCA site traffic is a very minor component of the total traffic volume that adding

another 20% YMCA traffic is hardly noticeable in the intersection performance measures.

The Baseline PM

Peak Hour site

traffic volumes

should be

increased by 20%

Figure 9. Modified Baseline Traffic Operations, with field sports

PC YMCA


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3. Assessing the Future Conditions Estimate and Its Analysis

The DeShazo Study assumes that the new gym, Rise School and therapy pool are the only new

traffic and parking that will be generated at the PC YMCA. Closer examination of future uses

over those considered in the baseline parking and traffic formulation suggests the following

additional considerations of the proposed 61,768 square-foot PC YMCA.

Additional Non-Activity Space

The space programming indicates that about 8,500 square feet of additional space will be

added to the building that is considered non-activity space.

a. Lobby, restrooms and circulation hallways, stairways and elevators are programmed to

increase by just over 7,500 s.f. This space type will be needed to allow access to the

various uses provided in the building. While it will make the building more functional

and feel roomier, in and of itself it is not expected to generate new traffic or parkingneeds.

b. Mens and womens locker rooms increase only slightly in size and is not expected to

generate new traffic or parking needs.

c. Office and administrative space, not including that for the Rise

School, increases by about 1,500 s.f. This increased space

addresses existing overcrowding but can be expected to generate

up to 3 additional parking spaces for additional administrative

and maintenance staff, with the vehicles for these additional staff

expected to arrive/depart during or near AM/PM peak hours.

Additional Activity Space

The space programming indicates that about 11,500 square feet of additional programmable

space will be added to the building. Notably, the new programmable space also includes about

9,500 square feet of space that was formerly outdoors but will now have year-round utility as

enclosed conditioned space.

An additional 3 spaces

more than in the Study

are suggested during the

AM and PM peaks due to

the additional office

space


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a. Child Watch (30 max) for parents while using the facility is assumed in the DeShazo

Study to retain the same baseline parking demand and generate the safe traffic, even

though the existing 1,180 s.f. is replaced by the proposed approximately 875 s.f.

b. The existing Pre-K (approximately 945 s.f., 2 teachers, 4 aids, 20 youth) will be absorbed

into the Rise School (5,955 s.f., 5 teachers, 10 aides, 60 students) and will add a net newparking demand for 9 staff plus shared parking for up to 60 parents to park for 15 to 30

minutes intermittently in the morning and early afternoon.

The Study Memorandum, dated 3-20-12, includes

consideration for an increase of 22 parking spaces, plus

associated in/out traffic in the morning and afternoon for 40

additional parents delivering youth to and from the Rise

School. The net provision of 13 additional spaces to support

the up to 60 parents bringing in and walking out their students

at the Rise School appears to be less than adequate. An amount of 5 more spaces is

suggested. The morning arrivals at the Rise School at somewhere around 9:00 a.m. will

coincide with the peak parking demand period for the PC YMCA.

c. The existing outside sport (basketball) court will be replaced with a new gymnasium. As

with the pool, the sport court would not have seen much use in the late October/early

November data collection time frame. Thus, all of the new parking and traffic for the

gymnasium will be considered as additional needs for the site. Since the gym can hold

two concurrent basketball games side by side, the critical

events in the gym would be weekday afternoon basketball

games. The programming considers two concurrent games,

two teams on the floor and two teams waiting with a peak of 95

additional parked vehicles plus associated arriving and

departing traffic. These vehicular estimates were estimated at arate of 1.0 vehicles per player and support staff. Using a 1.5 vehicle-to-player ratio, as

determined previously in this report, would result in the need to park 36 more vehicles

than in the Study.

d. The existing outdoor pool will be reconfigured as a therapy pool and placed indoor

adjacent to an improved lap pool. Though the overall space in the pool area is about

the same as existing indoor plus outdoor pools, the therapy pool will be available to be

used year round. The DeShazo Study includes additional parking and traffic for 20

members in the therapy pool. This is appropriate since the outdoor pool that would

have been used as the therapy pool was not in operation during the October/November

traffic and parking data collection. The current therapy activities, when provided duringthe cooler months, would take up room in the lap pool.

e. The adult fitness and spin rooms space is being enlarged by

1,350 square feet, or about a 24% increase in size. The

existing space is reportedly very crowded and will expand

into the new space with not much room for new exercise

positions. However, the existing facility usage is indicative of

what could evolve over time, so some additional usage is



are suggested due to the

Rise School during the

AM peak



are suggested due to the

gymnasium for the PM

peak

An additional 5 vehicles



AM and PM peak due to

the adult fitness and spin

area


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expected beyond existing, especially during the peak hours. An additional 5 parking

spaces and associated peak hour traffic are recommended for consideration.

f. Multipurpose Rooms will house the various exercise and conditioning classes that are

conducted in Hodges Hall, the racquetball court and the courtyard. Again, the existing

programs are reportedly very crowded and will expand into the new space with not

much room for new classes and programs. Some additionalusage is expected beyond the existing baseline, especially

during the peak hours, due to potentially larger spaces and

more designated spaces. An additional 10 parking spaces

and associated peak hour traffic are recommended for

consideration.

Background Traffic Growth

The DeShazo Study assumes a 1% growth in

background traffic on Preston Road. This

assumption is made despite the fact that the

traffic on Preston Road has been decreasing byabout 1% per year for the last 10 years. The

North Central Texas Council of Governments in

its 2035 Mobility Plan has forecast traffic

volumes of 18,160, essentially no increase from

the volumes measured in 2009.

An additional 10 vehicles



AM and PM peak due to

the multipurpose rooms

NCTCOG


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Trip Distribution onto Roadway Network

The distribution of inbound and outbound trips to the PC YMCA were estimated in the DeShazo

report using the existing peak period turning movement counts as an indicator of current

patterns that may apply in the future. Existing traffic counts are very low (


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Modification to the Parking and Traffic Impact Study Findings

Parking Demand

The results of this review of the parking and traffic study calls for an increase in the parking

supply needed at the PC YMCA above that identified in the DeShazo Study. The Baseline parking

demand is recommended to be increased by 8 spaces in the AM peak period and by 24 spacesin the PM peak period. In addition, for the redevelopment, the parking demand is

recommended to be increased by 23 spaces in the AM peak period and by 54 spaces in the PM

peak period. Thus, the parking spaces identified as needed in the DeShazo Study report and

Memoranda would be adjusted from 259 in the AM peak and 252 in the PM peak to a

recommended parking demand of 290 spaces in the AM peak and 330 spaces in the PM peak.

This modified estimate of the PC YMCA redevelopment at near peak operation would be

accommodated, at a high confidence level, within a 330 space underground parking garage. The

expected high confidence level peak demand exceeds that of the currently programmed

parking garage of 300 spaces. Notably, the peak parking demand was estimated for the highest

activity day of the year, with the remainder of the years activities gradually declining, and is

greatly influenced by the youth sports activities. Also, the PC YMCA will have control over the

programming of its facility and could adjust its gymnasium, class and meeting room

programming to keep activities within the confines of its parking supply.

Traffic Operations

The resulting increase in traffic activity still results in Level of Service A or B (nearly free flow)

traffic operations on Preston and acceptable Level of Service (LOS C, D or E) on the side streets

of Normandy and Shenandoah during peak hours. The impacts of the additional 78 vehicles

during the PM peak hour on the nearby arterial street system is very small less than 1.0

second of delay per vehicle. The minimal impact of the additional PC YMCA traffic on the traffic

operations of Preston Road is due to the very good existing traffic operations (very low delays)on Preston Road at Normandy Avenue. The dissipation of the PC YMCA traffic as it approaches

the Mockingbird and University intersections results in less than 1.0 second of delay per vehicle

change in traffic performance at those intersections.

The Synchro model of the traffic operations on Preston Road was used to assess the relative

sensitivity of the model for increases in traffic volumes to and from the PC YMCA. The

Normandy side street traffic from the PC YMCA would need to increase by over 100 more than

the redevelopment traffic during the AM or PM peak hour to begin to lower the traffic

operations on Preston Road to Level of Service D. Thus, the facility expansion, if operated in

the manner prescribed, will not pose operational issues for Preston Road.

There are various operational considerations that need to be considered on the adjacent city

streets to facilitate the intended traffic operations, which are discussed in the following section.


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4. Assessing the Identified Impacts, Issues and Recommended Mitigation

The DeShazo Parking and Traffic Study and Memoranda identified minimal impacts to the local

area roadway traffic operations. A few operational configurations regarding the roadways

adjacent to the site were proposed by the PC YMCA design team and by the residential

neighborhoods.

Intersection of Normandy at Preston

The offset intersection of Normandy Avenue at Preston Road currently operates both of the

offset legs of Normandy on the same signal phase, exposing vehicles and pedestrians to many

conflicting movements and allowing the opportunity for vehicle crashes and personal injury.

Notably, any of the options for improvement would require changes to the signal installation.

Realigned Intersection with No Offset -

The PC YMCA site development concepts,

developed by Good Fulton Ferrell, included

an option to realign Normandy Avenue to

get rid of the offset (GFF Exhibit A) shown

at right). The realignment creates a more

typical four-legged intersection with typical

pedestrian crossings. The departures from

the PC YMCA will predominantly turn left or

right onto Preston Road. Though not a

currently well used movement, the

straightened intersection may attract more

traffic to arrive and depart the PC YMCA via

Normandy Avenue west of Preston Road,which is a fear of many residents of the neighborhood west of Preston Road. The right and left

turn channelization from the Lee Engineering concept (see Exhibit 1 on the following page)

could be applied to the aligned intersection concept to eliminate the westbound through

movement at the intersection, making this an acceptable solution.

The neighborhood surrounding the PC YMCA

east of Preston Road retained Lee Engineering

to prepare alternative concepts for PC YMCA

site access directly from Preston Road that

would serve to eliminate the need for PC YMCA

traffic to circulate through the neighborhood.

The configuration (shown at right) would not be

acceptable to the residents west of Preston

Road for the same reasons cited above. This

configuration would leave the on-street parking

along Normandy and not discourage the local

street YMCA traffic circulation.


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Retain Existing Offset Intersection The

current configuration proposed for the site

retains the existing offset intersection. The

Normandy Avenue westbound approach to

Preston Road is widened by one lane width

toward the center of the offset intersection,somewhat lessening the offset distance

between the movements.

The configuration as proposed would not allay

the fears of the residents west of Preston that

PC YMCA traffic would increase on Normandy through their neighborhood. The PC YMCA design

team has proposed a traffic diverter that would push the westbound Normandy right turns past

the intersection not allowing the turn to Normandy west of Preston Road.

The safety of the retained offset configuration can be enhanced by splitting the eastbound and

westbound movements into two separate phases. The pedestrian crossing indications could be

incorporated with either or both of the Normandy approach movements. Actuated separately,

either westbound or eastbound phases would only interrupt the Preston Road traffic flow when

demanded and would eliminate many of the offset intersection conflicts.

Preston Road Southbound Left Turn Lane at Normandy The

residents consultant, Lee Engineering, also saw the potential need

to provide a left turn lane on Preston Road at Normandy Avenue,

particularly for access to the garage. The concept included

realigning the Normandy intersection to eliminate the offset, and

channelizing the westbound Normandy to only left and right turns,with the right turn movement channelized to a point beyond the

intersection. This channelization treatment could be added to

either of the Good Fulton Ferrell site concepts to address the

concerns of the residents west of Preston Road.

The left turn lane could be added to either GFF site configuration,

but the configuration shown at right in the Lee Engineering

concept creates a confusing traffic flow just east of the

intersection that may create unanticipated slower turning

movements from Preston Road and constrained turning radii and

thus would not be acceptable.

While this need for a left turn lane appears logical, the traffic

operations on Preston Road are at such good level of service that

there would be sufficient gaps in opposing northbound traffic to

allow the 60+ per hour southbound left turns into the site to not

incur much delay waiting for an acceptable gap to cross the northbound traffic.


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Normandy Queue Lengths Interference with Exiting of the Parking Garage

Noteworthy in the DeShazo report analysis were the results of the Sychro modeling that

indicated the length of the queues that would form on the westbound Normandy approach at

Preston Road. The queue lengths are expressed in terms of the length to the back of the queue

of cars, and is computed for the 50th

percentile occurrence (typical condition) and the 95th

percentile occurrence (generally the longest back of queue that would reasonably be expected).From the Synchro analysis of the redevelopment including the proposed signal timing

improvements, the PM peak hour is the more critical of the two peak periods, with a 50th

percentile queue length of 98 feet and a 95th

percentile queue length of 129 feet. Thus, to

avoid blockage of the exit of the garage, the garage driveway opening on Normandy Avenue

should be at least 129 feet from the stop line at Preston Road. The current site plan measures

only about 75 feet from the stop bar to a point at which the Normandy queue would block the

next car exiting the garage from entering either of the two lanes at the approach.

Parking Accommodations on Shenandoah, Connerly and Normandy East of Preston

If the proposed 300 space parking garage under the PC YMCA is made attractive and convenient

to the drivers attending the youth field sports, with direct access from the garage to the field

level, these drivers can be attracted away from on-street parking on the local streets. The users

of the PC YMCA building facilities are not expected to be attracted to use the curbside parking

along Shenandoah Street or Connerly Drive adjacent to the PC YMCA if the parking garage

provides ample, well secured parking spaces and all-weather access directly from the garage to

the facility activities. To encourage use of the parking garage by all PC YMCA activities including

the field sports, special restrictions on parking along Shenandoah Street and Connerly Drive

should be put in place before the redevelopment is completed. Parking accommodations on

Shenandoah and Connerly east of Preston should be restricted to neighborhood parking only,

to force utilization of the parking garage and mitigate the need to circulate through the

neighborhood looking for parking. The 15 spaces on Normandy at the church should berestricted to non-PC YMCA usage except for handicap and certain designees.

Parking and traffic impacts on Shenandoah, Normandy and San Carlos West of Preston Road

Considering the attractiveness and convenience of the proposed 300 space parking garage

under the PC YMCA with direct access up to the facility, the users of the PC YMCA are not

expected to be attracted to use the already crowded curbside parking along Normandy Avenue

west of Preston Road. No special restrictions on parking along Normandy Avenue or

Shenandoah Street are anticipated to be needed nor are they expected to be desired.

Notably, in the DeShazo analysis of the extended impact area, no site traffic was distributed to

and from the local streets west of Preston Road - Shenandoah Street, Normandy Avenue and

San Carlos Drive. With design refinement, Normandy Avenue was considered to have a diverter

at Preston Road that would not allow east-west cross traffic to access the PC YMCA. However,

with a sizable portion of the PC YMCA membership residing in the area west of Preston Road

north of Mockingbird, it is expected that the traffic assumed to use Normandy in the Parking

and Traffic Study would utilize either Shenandoah or San Carlos as an alternative route. It may

be that the members who live west of Preston prefer to walk to and from the YMCA, and would


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be well served by enhancing the safety of the pedestrian crossing of Preston Road. The 5%

distribution of traffic to and from the site should be assigned proportionately to San Carlos and

Shenandoah. These volumes are less than 10 during the peak hour, so their impact on the

intersections of Shenandoah and San Carlos at Preston Road are approximately 1.0 second of

delay or less per vehicle.

5. Other Considerations.

Several other issues were brought forward by citizens and requested to be included as

considerations for this review of the Parking and Traffic Study for Park Cities YMCA

Redevelopment. Many of these considerations were already under review, but some were

additional elements of consideration. The following are several of these other considerations.

The level of intensity of arrivals and departures at PC YMCA that would make LOS

unacceptable (sensitivity testing of the traffic model).

The Synchro model of the traffic operations on Preston Road, prepared by DeShazo and

checked for accuracy by Freese and Nichols, was used to assess the relative sensitivity of the

model for increases in traffic volumes to and from the PC YMCA. Several conditions of increased

traffic volumes and configurations of signal operation were assessed.

x The site-related traffic movements (WB LT, WB Thru, WB RT, SB LT, NB RT and EB Thru)

were increased by 50%, 100%, and 150% to examine the sensitivity of the modeled

street network to increased levels of activity at the PC YMCA. At each level, the green

time allocations to each approach were optimized to give the best overall delay value

for the intersection, giving preference to the through movements on Preston Road. The

following observations resulted:

o 50% more than the peak PC YMCA traffic operations slightly degrades from theLOS A, as found in the DeShazo Study for the proposed redevelopment, to LOS B

on southbound Preston Road, while keeping WB left turn at not worse than LOS

E during the PM peak hour. The degradation is due to increased interference of

the southbound left turn movement with the southbound through movement,

due to the absence of a dedicated left turn bay.

o 100% more than the peak PC YMCA traffic operations further degrades to LOS

C on southbound Preston Road, LOS B northbound, while keeping WB left turn at

not worse than LOS E during the PM peak hour, due to southbound left turn

interference.

o

150% more than the peak PC YMCA traffic operations further degrades to LOSE on southbound Preston Road, still LOS B northbound, while keeping WB left

turn at not worse than LOS E during the PM peak hour. The absence of the

southbound left turn lane on Preston Road would be a severe limitation at this

level of operation.

x If the background traffic on Preston Road was to increase by 25% over that in the model

(recall that historical trends indicate that a 1% per year growth is a generous growth


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rate), then the point at which the Preston Road traffic degrades would be lowered to

about 100% more than PC YMCA peak traffic.

x With provision of a southbound/northbound left turn lane at Normandy, southbound

and northbound Preston Road would continue to operate at LOS B even beyond the

level of 150% more PC YMCA peak traffic.

Conditions under which Traffic Police Control Might be Needed.

Given the ability of the existing roadway network to absorb the proposed PC YMCA

redevelopment after completion, there may still be some instances of concentrated traffic

conditions that may require supplemental police traffic control. The traffic patterns considered

at the YMCA are generally a steady inflow and outflow of members using the facility for a

period of one to two hours throughout the day. There are peak times of day when the usage is

heavier than others, but the arrivals are spread out even within the peak period. Even the Rise

School has a less stringent time of arrival and departure that distributes the traffic over greater

time than a normal school. If a special event that caused participants and observers to arrive

and depart in large numbers over a short period of time were to be held at the PC YMCA, thenthe associated traffic might overwhelm the roadway network and intersection controls such

that uniformed police should be retained to manually control traffic at the Preston Road

intersections with Normandy and Shenandoah. Such events might include the previously held

triathlon, a combination of sporting events in both the gymnasium and on the field, or special

events with specific beginning and ending times, such as concerts, with high traffic over short

duration should be avoided.

Conditions under which drivers will seek alternate routes to and from the PC YMCA.

The DeShazo study assumed that 85% of the traffic would enter the PC YMCA parking garage

from north and south on Preston Road, with the other 15% of traffic using the local streets

northeast of the intersection of Connerly at Shenandoah. All traffic was assumed to go into andcome out of the underground parking garage. There may be a tendency for traffic coming from

the north on Preston to avoid the signal controlled intersection at Normandy and make their

left turn at Shenandoah to mix with the 15% traffic on Connerly. This tendency would be

particularly attractive if any on-street parking is made available on Shenandoah or Connerly

Streets.

Additionally, the placement of restrictions on traffic to and/or from the YMCA to use Normandy

Avenue west of Preston Road would tend to push this traffic onto Shenandoah and San Carlos

Streets. However, this existing traffic movement had very low traffic counts (5 vehicles per hour

or less) during the AM and PM peak hours, so the impact of splitting this movement among twostreets is considered to be negligible.

Parking Garage Operations Issues.

As noted previously in this report, with the proposed redevelopment, the queue lengths on

westbound Normandy Avenue at Preston Road is expected to have a back of queue length of 98

feet during the typical PM peak hour and potentially may reach up to a length of 129 feet.

Thus, to avoid blockage of the exit of the garage, the garage driveway opening on Normandy


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Avenue should be at least 129 feet from the stop line at Preston Road. The current site plan

measures only about 75 feet from the stop bar to a point at which the queue would block the

next car from entering either of the two lanes at the approach. Notably, the residential

frontage on the south side of Normandy Avenue begins at about 200 feet east of Preston Road,

so the entry to the underground garage should be placed somewhere between 129 feet and

200 feet from Preston Road.

The one ingress/egress for the garage should be adequate to serve the facility. The pattern of

arrivals suggests a very spread out loading and unloading of the garage. The PM peak hour

loading at the westbound Normandy approach to Preston indicates a need to process at least

10 vehicles every 2 minutes out of the garage. The unmetered ramps should be able to process

one vehicle every 6 to 8 seconds, or a rate of 15 to 20 vehicles every 2 minutes. Thus, there

should not be queuing on the one exit ramp under typical peak operating conditions, unless

blocked by queuing on Normandy Avenue.

Also in the garage, the access to and from the majority of the parking stalls is indirect, requiring

enter/exit traffic circulation around the base of the pool to traverse to and from the parking

areas. The joint usage agreement with the church will complicate access from the garage to the

PC YMCA interior and exterior doorways to accommodate church usage without going through

the PC YMCA.

The circulation for parking for the field activities appears to be such that it would be very

circuitous for youth and adults to park in the garage and walk to the field, potentially causing

field sports attendees to prefer to park along neighborhood streets. This condition would

encourage parents to park along the streets nearby the field. The popular usage of the parking

garage for activities on the field would be facilitated by providing an elevator from the middle

of the garage to the north edge of the building at the south edge of the field.

The impacts of these usage changes over time will be most noticed in the parking patterns at

the PC YMCA. When facility usage increases, the parking garage will begin to approach its

capacity. If members experience congestion in the parking garage or difficulty finding a space,

they will tend to find a more convenient place for them to park, turning to the on-street parking

available in the neighborhood streets.

Increased PC YMCA usage by affiliated groups.

As shown in the parking baseline information, there are extended periods throughout the day

every day of the year that parking demand exceeds the parking supply at the existing PC YMCA.So, for non-YMCA activities to request to use the PC YMCA facility would seem to be

unthinkable. However, with the provision of the 300-space parking garage, there will be times

of the day between 10:00 a.m. and 4:00 p.m. and after 7:00 p.m. that the PC YMCA will have

available capacity in their building space and parking garage to consider hosting these outside

group meetings.


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Increase in PC YMCA membership and activity as general outcome of improvements.

It is an anticipated secondary impact of the PC YMCA redevelopment that the newer, slightly larger

facility with more event accommodations will increase the membership at PC YMCA. With increased

membership will come increased facility usage, not just in the additional programmed space as noted in

this report, but a general surge in usage overall. It is also possible that the pattern of monthly, weeklyand daily variation may change with the new facility, as new programs evolve to respond to changes in

membership. Thus the importance of the traffic operations sensitivity analysis and peak parking

demand estimates.

The addition of a Gymnasium at the PC YMCA will allow them to host basketball and volleyball games,

which PC YMCA youth currently have to play at other locations. Given the current schedule of the sports

seasons, depicted on the timeline in Figure 11, the PC YMCA will need to schedule games in the

gymnasium when there are not games on the field. Otherwise, parking demand would be expected to

exceed supply. Alternatively, the PC YMCA could reorganize PM peak classes and other activities in the

facility to offset the need for PM peak parking if a field and Gymnasium game were both scheduled.

Figure 11. Youth Sports Seasons (2011 dates noted)

review of the parking and traffic study for park cities ymca redevelopment

Documents