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Latter Day/PP-SY 930520TRAFFIC STUDY The Church of Jesus Christ of Latter-Day Saints Coppell, Texas Prepared for: John R. Horton Architect Prepared by: G.T. (Tom) Walton, P.E. Consulting Traffic Engineer May 1993 EXECUTIVE SUMMARY The new Church of Jesus Christ of Latter-Day Saints facility in Coppell is being planned. A traffic study of the proposed plan and its effect on the area is required by the City of Coppell. The details of the study are given in the following pages. The traffic study includes a review of the site plan, a survey and review of the traffic situation on MacArthur Boulevard at the church's activity time, traffic manuevers to enter and leave the site, the traffic to be expected from the site and recommendations of steps to be taken to enhance the traffic flow into and out of the site. The results of the study can be summarized as follows: Access to the site can be adequately provided by the single divided drive. A deceleration/right turn lane will enhance drive operation. 3. U-turn manuevers on MacArthur Boulevard can be safely made. A minor adjustment to the design of the drive will improve outbound operation. The need for additional access to the site is not indicated. I. SITE PLAN II. The location of the site for the new church dictates that its access is limited to MacArthur Boulevard. The plan shows one drive which is made up of two one-way pavements, both 24' wide, separated by a landscaped median 10' wide. The drive extends into the site approximately 20' to a 24' wide circulation aisle which extends across the front of the church building and connects to 90° parking areas along both the east and west sides of the building. There is no entrance on the front or north side of the building, but there are entrances on both the east and west sides, as well as at the rear. A large parking area is provided to the rear of the building. The proposed site plan shows a deceleration lane across the entire MacArthur Boulevard frontage of the site. A sidewalk is also shown across the site, which connects to an existing walk along the south side of MacArthur to the east of the site. Notations have been made on the site plan of negotiations with the Coppell Indepen- dent School District to obtain an easement across the school frontage for the deceleration lane and also an easement across the south side of the school tract to gain access to Samuell Road. AREA ACCESS/CONDITIONS The site for the new church is located in the north eastern portion of the City of Coppell. The two primary roads used to approach the site are MacArthur Boulevard and Samuell Road. MacAurthur Boulevard - According to the City of Coppell Major Thoroughfare Plan given in the Roadway Functional Classifications and Design Standards for the City of Coppell, MacArthur Boulevard is a Major Arterial and is planned to have three lanes in each direction with a 17' median. At this time, it is operating as a four lane road with two lanes in each direction. It has two roadways 22' wide and a 36' median. By design, when completed, MacArthur Boulevard is planned to have a capacity of 35,000 trips per day. MacArthur is the eastern most arterial in the City of Coppell. It is also important from a regional perspective as it provides a connection from SH 183 in Irving on the south to Lewisville on the north. In Coppell, it connects with Sandy Lake Road approxi- mately 3/4 mile south and Beltline Road another mile south of Sandy Lake Road. These roadways connect to IH 35E, Carrollton and points east. -1- · · SITE III, In the area of the church site, MacArthur has a 60' median opening opposite the east property line of the site which serves the residential street, which intersects MacArthur from the north. A left turn lane with 80' of storage is provided for eastbound traffic. There is another 60' median opening 422' west. A left turn lane with 80' of storage is pro- vided for westbound traffic. These geometric features are shown in the drawing and also the approximate location of the site. Samuell Road - In the city of Coppell Thoroughfare Plan, Samuell Road is indicated as a Collector street with parking permitted on both sides. It is a reinforced concrete roadway with curb and gutter and the pavement is 44' wide B-B. Samuell Road has a total length of approximately one mile. It runs north and south from Sandy Lake Road to MacArthur Boulevard. At the present time, there is a temporary span-wire mounted traffic signal at the intersection of Samuell and Sandy Lake. There is a four-way stop control at the intersection of Samuell Road and Parkway Boulevard. A permanent traffic signal is now under construction at the intersection of Samuell Road and MacArthur Boulevard. This signal will be the closest major traffic control device to the site of the new church. The area around the proposed church is rapidly develo- ping. To the north and west of the site are completed residential subdivisions. Between the site and Samuell Road to the west is an undeveloped school site. The site is bordered on the east by a residential tract that is now under development. Further to the south and east there are several rapidly developing residential subdivisions. Traffic approaching the site from the south on MacArthur Boulevard will have to make a U-turn at the median opening west of the church and a right turn into the drive. To return to the south, a simple right turn out of the drive is all that is necessary. Those approaching the site from the north on MacArthur need only make a right turn into the drive. To return, a right turn from the drive, followed by a U-turn at the median opening is the most obvious route. An analysis of the U-turn manuevers is given later in this study. U-TURN AND DRIVE OPERATION Traffic approaching the site from the southeast on MacArthur Boulevard will make a U-turn at the median opening opposite the school site. They will then make NEW CHURCH SITE LAKE FOREST DRIVE IV. Ve VI. a right turn into the drive. When departing the site, they can simply make a right turn onto MacArthur. Those approaching from the northwest will enter the site by making a right turn into the drive. When departing, they may turn right from the drive and enter the left turn lane at the intersection median opening to make a U-turn. Departing traffic will have to cross both eastbound lanes to enter the left turn lane, so large gaps in eastbound traffic on MacArthur will be important. The inbound traffic will have to cross both lanes of east- bound traffic to make their U-turn and turn into the drive. A deceleration and right turn lane will give them a refuge prior to actually making their right turn. TRAFFIC GENERATION Based on information given in the January 1991 5th Edition of Trip Generation, published by the Institute of Transportation Engineers, the traffic generated during the peak hour of church activities is 239 trips. This figure is calculated based on the proposed 25,506 feet2 size of the new church. CHURCH DEMOGRAPHICS AND ACTIVITY SCHEDULE The new church is planned to be used by two separate congregations. They will attend servcies at the new facility at different times on Sundays. One group will be made up of church members who live in Coppell and southern Lewisville and Flower Mound. They will meet at the new church from 8:00 a.m. to 11:00 a.m. The other group will be members living in Carrollton who will meet at the new church from 1:00 p.m. to 4:00 p.m. It is estimated that the first group will have 254 mem- bers and the second will have 208 members. SITE IMPACT ANALYSIS In order to determine the effect that the new church will have on MacArthur Boulevard, a traffic impact analysis was completed. The analysis involved a study of (1) the effectiveness of the proposed driveway, (2) the effect that the U-turns at the two median openings will have on MacArthur traffic, (3) the need for and design of a deceleration lane on MacArthur Boulevard, and (4) the need for access from the site across the school site to Samuell Road. The analysis assumes a worst case situation. In this case, that means the traffic volume for the church is that calculated from -3- the Trip Generation Manual. The inbound to outbound assumption is that 50% of the peak hour traffic is inbound and 50% outbound. With the two existing median openings on MacArthur, it will not be possible to construct one to serve the church traffic directly. The proposed driveway will operate with only right turns inbound and right turns outbound. Both the inbound and outbound flows will operate in a single file. The large (24') inbound lane will allow a smooth turn and allow traffic to clear the right lane of MacArthur Boulevard quickly. The outbound lane is also 24' wide, but this may not be desirable. A lane that wide will encourage exiting traffic to line up two abreast. This can cause visibility problems for the right vehicle. In addition, both cars may attempt to make their right turns at the same time. Consideration should be given to reducing the width to the exit lane to 14' to 16'. The median island proposed in the drive will eliminate any conflict between inbound and outbound traffic. The size and design of the drive will allow it to accomodate the expected traffic volumes easily. U-turns on a divided thoroughfare can cause prob- lems. The potential for problems is effected by several factors, including the width of roadway available for the turning manuever, the availability of a protected storage lane to wait to make the turn, the visibility of traffic approaching from the opposite direction and the volume and regularity of opposing traffic. On MacArthur Boulevard, in- bound traffic to the site can make use of the existing westbound left turn lane for the opening west of the site. The outbound traffic can make use of the existing eastbound left turn lane for the opening at the east boundary of the site. Visibility to the east along MacArthur is clear for over 1000'. To the west, there is a gentle rise, but approaching traffic can be seen from west of the Samuell Road intersection. In order for the largest private auto, i.e., van, pickup, etc., to make a U-turn, a minimum width of 48' of pavement is needed. On MacArthur Boulevard, the width of pavement from the right side of the left turn lane to the right curb of the opposing lanes is measured at 58'. The required turn can therefore be made with relative ease. The primary concern when making a U-turn is with traffic coming from the opposite direction. At an intersection such as the one at the eastern boundary -4- of the church site, there is also concern with vehicles entering from the cross street. A survey was done of the existing traffic along MacArthur Boulevard. The amount of traffic east- and westbound was counted and also the various turning movements at the intersection were recorded. The survey was done on Sunday to cover the beginning and ending times for the services for the two church groups. The Sunday services are the only times that the whole group attends at one time. There is no time when both groups are at one service. The results of the survey are shown in the following table and drawing. The drawing shows the various movements that were recorded. The survey shows that the through movement volumes peak at just over 60 vehicles per direction in a 15 minute period. If the traffic were distributed evenly over time, there would be a maximum of four vehicles per minute or one vehicle every 15 seconds. Since the traffic was actually observed passing in groups of from two to five vehicles, there are often large gaps between cars. These gaps will allow easy flow of traffic in and out of the driveway and also little conflict with traffic making U-turns at either of the median openings. In the future, there may be some increase in traffic on MacArthur as the residential areas to the south and east build out, but it is doubtful that the Sunday volumes will increase to the point of creating a problem from the church. In addition, the traffic signal that is under construction at the intersection of MacArthur Boulevard and Samuell Road can be expected to provide gaps in the traffic approaching from the west. The church traffic, either exiting at the driveway or U- turning at the western median opening, will be able to take advantage of these gaps. The need for a deceleration lane and right turn lane to serve a driveway is generally demonstrated by a large inbound traffic volume and/or a congestion situation that may create a queue on the street approaching the drive. The inbound traffic volume during the peak hour of the church activity should be easily accomodated by the 24' wide entry aisle of the drive. The only way that queueing might occur is if an onsite congestion situation were to make it impossible for entering traf- fic to clear the drive. If a very large percentage of the congregation were to arrive at virtually the same time, this might occur. If a deceleration lane is pro- vided, it should be 11' to 12' wide and have the same design as the left turn lanes at the median openings, i.e., 80' of storage length and 120 of transition. -5- 5/16/93 SUNDAY 7:45-8:00a.m. 8:00-8:!5a.m. 8:15-8:30a.m. lO:30-10:a5a.m. lO;.~5-]!:OOa.m. ll:O0-1!:lSa.m. ll:lS-!!:30a.m. 12:30-!2:~5p.m. 12:45-1:OOp.m. l:O0-!:lSp.m. l:lS-l:30p.m. 3:30-3:45p.m. 3:45-4:00p.m. 4:00-4:15p.m. 4:15-4:30p.m. Eastbound Eastbound Westbound Westbound Southbound Southbound Left (EBL) Right(~,~BR) Left (SBL) Right(SBR'~l 12 2 8 2 I 3 7 2 8 1 11 1 7 ! I 1 18 3 19 6 3 2 12 32 3 I I 2 40 3 30 3 5 2 31 2 43 2 3 2 39 2 53 4 11 3 35 ~ 62 3 25 2 57 2 4 1 45 4 52 5 6 3 50 1 45 4 2 6 51 1 45 1 3 3 46 tt8 5 1 5 64 2 61 3 3 NEW CHURCH SITE LAKE FOREST DRIVE The need for an additional accessway to the site across the school site from Samuell Road would be demonstrated in the same way as the decleration lane, if the proposed drive on MacArthur Boulevard could not handle the expec- ted traffic into and out of the site. Another consi- deration might be the elimination of a serious U-turn hazard. In the proposed situation, the expected traffic volume should not create an operational problem at the drive. In addition, the information given above indi- cates that U-turns which must be made to approach the site can be safely done by making use of the existing median openings and left turn lanes. VIII. CONCLUSIONS AND RECOMMENDATIONS The information developed in this study leads to a num- ber of conclusions and recommendations. Conclusions: The proposed site plan will provide smooth circulation of on-site traffic. The traffic generated by the proposed church can be adequately served by the single drive proposed. Existing and expected traffic on MacArthur Boulevard will provide large gaps in traffic for entering and departing traffic. The eastbound gaps can be enhanced by the new traffic signal. The U-turns necessary to approach and leave the site can be safely made. A deceleration and right turn lane is not indicated by expected traffic volume, but will enhance entering traffic. The need for access across the school tract to the west of Samuell Road is not indicated by the expected traffic, especially with the deceleration/right turn lane. Recommendations: The proposed driveway design should be adjusted to pro- vide a 14' to 16' exit lane to eliminate the possibility of a double right turn movement. The deceleration/right turn lane should be designed with 80' of storage and 120' of transition. Members of the congregation who live south, east or west of the site should be requested to approach the site from Samuell Road onto MacArthur and return to the south on MacArthur to eliminate the need for as much of the U-turning traffic as possible. -6-