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Traffic Study DRAFT REPORT www.transportationcollaborative.com To: Josh McKinney, PLA, Principal Measure Group From: Matt Pacyna, PE, Principal Transportation Collaborative & Consultants, LLC Date: April 11, 2025 Subject: Santa Vera Apartments Traffic Study; Chanhassen, MN INTRODUCTION TC2 completed a traffic study for the proposed Santa Vera Apartments development in the City of Chanhassen. The subject site, shown in Figure 1, is generally bound by City Center Park to the west, Saratoga Drive to the north, Laredo Drive to the east, and Chanhassen Elementary School to the south. The proposed development is a 59-unit market-rate apartment, which is immediately south of an existing 18-unit apartment complex. The main objectives of the study are to quantify existing traffic operations within the study area, evaluate potential impacts of the proposed development, and recommend improvements, if necessary, to ensure safe and efficient operations for all users. The following study assumptions, methodology, and findings are offered for consideration. Figure 1 Subject Site Subject Site Laredo Dr Kerber Blvd Del Rio Dr 78th St Powers Blvd (CR 17) 76th St Market Blvd Santa Vera Apartments Traffic Study April 11, 2025 Page 2 EXISTING CONDITIONS Existing conditions were reviewed within the study area to establish current traffic conditions to help determine impacts associated with the proposed development. The evaluation of existing conditions included collecting traffic volumes, observing transportation characteristics, reviewing crash history, and analyzing intersection capacity, which are described in the following sections. Traffic Volumes Vehicular intersection turning movement and pedestrian / bicyclist counts were collected on Wednesday March 26, 2025. The counts were generally collected from 7 to 9 a.m. and 4 to 6 p.m. with 13-hour counts (i.e., 6 a.m. to 7 p.m.) at the Kerber Boulevard / Santa Vera Drive and Laredo Drive / Saratoga Drive intersections. • Kerber Boulevard and Santa Vera Drive • Santa Vera Drive / Saratoga Circle and Saratoga Drive • Laredo Drive and Saratoga Drive • Laredo Drive and Del Rio Drive To illustrate how traffic volumes at study area intersections vary throughout the day, the traffic volume profiles by time-of-day are illustrated in Figure 2. Note that the adjacent Chanhassen Elementary School starts at 7:45 a.m. and ends at 2:15 p.m. Figure 2 Intersection Volume by Time of Day Transportation Characteristics Observations were conducted within the study area to identify various transportation characteristics such as roadway geometry, traffic controls, speed limits, and multimodal facilities. A general overview of key roadways within the study area is as follows: • Kerber Boulevard – a 2-lane undivided major collector roadway with multimodal facilities along both sides of the roadway. The speed limit is 40-mph with a 20-mph school zone speed limit near the elementary school. • Laredo Drive – a 2-lane undivided local roadway with a sidewalk along the west side of the roadway; the speed limit is 30-mph with a 15-mph school zone speed limit near the elementary school. All other study area roadways are 2-lane local roadways with limited multimodal facilities and a 30-mph speed limit. Each study intersection has side-street stop control. Existing geometrics, traffic controls, and volumes within the study area are shown in Figure 3. 0 50 100 150 Intersection VolumeKerber Blvd / Santa Vera Dr Laredo Dr / Saratoga Dr 550 550 700 650 1 5 0 300800303,7504, 0 0 0 1,300Figure 3Existing Conditions Santa Vera Apartments Traffic Study Legend AM Peak Hour VolumePM Peak Hour VolumeEstimated ADT VolumeStop Sign XXX(XXX)X,XXX NKerber BlvdSanta V e r a D r Saratoga DrLaredo DrDel Rio Dr 0 (0)0 (0)0 (0) 0 (2)0 (0)16 (12)0 (0)20 (63)2 (9)0 (0)63 (42)1 (2)11 (16)149 (132)5 (3)9 (13)42 (200)4 (21)3 (3)9 (11)12 (13)8 (12)20 (5)12 (11)0 ( 0 ) 2 ( 1 ) 25 (28)1 (3) 24 (26)0 (0)0 ( 0 ) 8 ( 2 ) 4 ( 2 ) 0 ( 0 ) 3 ( 5 ) 17 ( 2 4 )1 (2)1 (1)23 (25)0 (0)3 (0)0 (1) 1 (10)30 (18)8 (19)11 (43) 12 (10)31 (24) 0 (0)3 (2)1 (3)19 (62) 0 (0)61 (42) 1,100 Santa Vera Apartments Traffic Study April 11, 2025 Page 4 Crash History Five (5) years of crash history were reviewed from 2020 through 2024 using MnDOT’s Crash Mapping Analysis Tool (MnCMAT), which identified two (2) intersection-related crashes within the study area. One (1) crash occurred at the Santa Vera Dr / Chippewa Trail intersection and one (1) at the Laredo Drive / 76th Street intersection. Neither crash resulted in a serious injury. Thus, there does not appear to be any existing safety issues in the study area from a crash frequency or severity perspective. Intersection Capacity Intersection capacity was evaluated using Synchro / SimTraffic Software (version 11), which uses methods outlined in the Highway Capacity Manual, 6th Edition. The software is used to develop calibrated models that simulate observed traffic operations, account for peaking characteristics, and identify key metrics such as intersection Level of Service (LOS) and queues. These models incorporate collected traffic, pedestrian, and bicyclist volumes, traffic controls, heavy commercial vehicle activity (i.e., buses and trucks), and driver behavior factors. Level of Service (LOS) quantifies how an intersection is operating. Intersections are graded from LOS A to LOS F, which corresponds to the average delay per vehicle values shown. An overall intersection LOS A though LOS D is generally considered acceptable in the study area. LOS A indicates the best traffic operation, while LOS F indicates an intersection where demand exceeds capacity. For side-street stop-controlled intersections, special emphasis is given to providing an estimate for the level of service of the side-street approach. Traffic operations at an unsignalized intersection with side- street stop control can be described in two ways. First, consideration is given to the overall intersection level of service, which accounts for the total number of vehicles entering the intersection and the capability of the intersection to support the volumes. Second, it is important to consider the delay on the minor approach. Since the mainline does not have to stop, most delay is attributed to the side-street approaches. It is typical of intersections with higher mainline traffic volumes to experience high-levels of delay (i.e., poor levels of service) on the side-street approaches, but an acceptable overall intersection level of service during peak hour conditions. Results of the existing intersection capacity analysis, shown in Table 1, indicate that all study intersections and approaches operate at an acceptable LOS B or better during the typical weekday a.m. and p.m. peak hours. In addition, peak queues at the study intersections range from about one (1) to two (2) vehicles. Note that there is increased activity for a short-duration (i.e., approximately 15 minutes) near the start / end times associated with the adjacent Chanhassen Elementary School. However, this increased activity does not significantly impact the study intersections or their operations. Thus, there are no significant existing operational issues from an intersection capacity perspective. Level of Service Average Delay / Vehicles Stop, Yield, and Roundabout Intersections Signalized Intersections A < 10 seconds < 10 seconds B 10 to 15 seconds 10 to 20 seconds C 15 to 25 seconds 20 to 35 seconds D 25 to 35 seconds 35 to 55 seconds E 35 to 50 seconds 55 to 80 seconds F > 50 seconds > 80 seconds Santa Vera Apartments Traffic Study April 11, 2025 Page 5 Table 1 Existing Intersection Capacity Study Intersection Traffic Control Level of Service (Delay) AM Peak Hour PM Peak Hour Kerber Boulevard and Santa Vera Drive SSS A / B (12) A / B (12) Santa Vera Drive and West Site Access SSS A / A (9) A / A (9) Santa Vera Drive / Saratoga Circle and Saratoga Drive SSS A / B (10) A / A (9) Laredo Drive and Saratoga Drive SSS A / A (9) A / A (9) Laredo Drive and East Site Access SSS A / A (9) A / A (9) Laredo Drive and Del Rio Drive SSS A / B (10) A / A (9) SSS – Side-Street-Stop PROPOSED DEVELOPMENT The proposed development is generally bound by City Center Park to the west, Saratoga Drive to the north, Laredo Drive to the east, and Chanhassen Elementary School to the south. The proposed development is a 59-unit market-rate apartment, which is immediately south of an existing 18-unit apartment complex. If approved, the site would have a total of 77 units (18-existing, 59-proposesd). For study purposes, the project was assumed to be open to residents in the year 2027. Access to the proposed development is planned via the existing driveways along Santa Vera Drive and Laredo Drive that currently provide access to the existing apartments. No new access is planned. Sidewalk connections are planned to the existing City Center Park trail to the west, as well as the sidewalk along the west side of Laredo Drive. Santa Vera Apartments Traffic Study April 11, 2025 Page 6 TRAFFIC FORECASTS Traffic forecasts were developed for year 2028 build conditions, which represents one-year after opening. The traffic forecasts account for general background growth and trip generation from the proposed development. The following information summarizes the traffic forecast development process. Background Growth To account for general background growth in the study area, an annual growth rate of one (1) percent was applied to the existing traffic volumes to develop year 2028 background traffic forecasts. Note that historical ADT volumes within the study area have been steady or decreasing over the last 10+ years. Therefore, the assumed growth rate provides a relatively conservative estimate for analysis purposes. Development Trip Generation A trip generation estimate for the proposed development was created using the ITE Trip Generation Manual, 11th Edition, which includes trips for typical weekday a.m. and p.m. peak hours, as well as daily. The proposed development, shown in Table 2, is estimated to generate 41 a.m. peak hour (10 in / 31 out), 46 p.m. peak hour (29 in / 17 out), and 454 daily (227 in / 227 out) trips. No modal reductions were applied to provide a more conservative estimate. Note that the average trip rates for a low-rise multi-family residential unit represent 0.4 trips / unit during the a.m. peak hour, 0.51 trips / unit during the p.m. peak hour, and 6.74 trips / unit per day. Table 2 Trip Generation Summary Land Use Type (ITE Code) Size AM Peak Hour PM Peak Hour Daily In Out In Out Existing Apartments (220) 18 units 2 5 6 3 122 Proposed: Multifamily Housing: Low-Rise (220) 59 units 10 31 29 17 454 Total Site Trips 77 units 12 36 35 20 576 Site generated trips for the proposed development were distributed throughout the study area using the directional distribution shown in Figure 4, which is based on a combination of existing area travel patterns and engineering judgment. Figure 4 also shows the proposed development site trips at the study intersections. The resultant year 2028 build condition traffic forecasts are illustrated in Figure 5. YEAR 2028 BUILD CONDITIONS To understand impacts associated with the proposed development, a future intersection capacity analysis was completed for year 2028 build conditions. Results of the year 2028 build capacity analysis shown in Table 3 indicate that that all study intersections and approaches will continue to operate at an acceptable LOS B or better during the typical weekday a.m. and p.m. peak hours. Minimal change to intersection delays and queues are expected, which is a result of the relatively low trip generation of the proposed development and the reserve capacity within the adjacent roadway network. Thus, no operational issues are expected as a result of the proposed development from an intersection capacity perspective. Figure 4Site Generated Trips Santa Vera Apartments Traffic Study +2750 (0)0 (0) 0 (0)5 (18)0 (0)0 (0)18 (9)0 (0)60% +175 +45+65+6 52 (4)0 (0)0 (0)2 (4)0 (0)0 (0)0 (0)1 (3)0 (0)5 (3)3 (2)5 (3)15% 10% 15% Legend AM Peak Hour Site TripsPM Peak Hour Site TripsADT Site TripsStop SignDirectional Distribution XXX(XXX)+XXX N 0 ( 0 ) 13 ( 8 ) 0 (0)5 (11) 0 (0)0 (0)0 ( 0 ) 0 ( 0 ) 0 ( 0 ) 0 ( 0 ) 0 ( 0 ) 0 ( 0 )0 (0)0 (0)0 (0)0 (0)0 (0)0 (1) 0 (0)0 (0)8 (0)0 (0) 0 (0)0 (0) 0 (0)18 (9)5 (18)0 (0) 0 (0)0 (0) 740 565 895 715 1 5 5 310825303,9504, 2 0 0 1,600Figure 5Year 2028 Build Conditions Santa Vera Apartments Traffic Study Legend AM Peak Hour VolumePM Peak Hour VolumeEstimated ADT VolumeStop Sign XXX(XXX)X,XXX NKerber BlvdSanta V e r a D r Saratoga DrLaredo DrDel Rio Dr 0 (2)16 (12) 26 (83)2 (9) 83 (52)1 (2)13 (20)154 (136)5 (3)12 (18)43 (206)4 (22)3 (3)10 (14)12 (13)13 (15)24 (7)17 (15)0 ( 0 ) 15 ( 9 ) 26 (29)6 (14) 25 (27)0 (0)0 ( 0 ) 8 ( 2 ) 4 ( 2 ) 0 ( 0 ) 3 ( 5 ) 18 ( 2 5 )1 (2)1 (1)24 (26)0 (0)3 (0)0 (1) 1 (10)31 (19)9 (20)11 (44) 12 (10)32 (24) 0 (0)21 (11)6 (21)20 (64) 0 (0)63 (43) 1,400 Santa Vera Apartments Traffic Study April 11, 2025 Page 9 Table 3 Existing Intersection Capacity Study Intersection Traffic Control Level of Service (Delay) AM Peak Hour PM Peak Hour Kerber Boulevard and Santa Vera Drive SSS A / B (12) A / B (12) Santa Vera Drive and West Site Access SSS A / B (10) A / A (9) Santa Vera Drive / Saratoga Circle and Saratoga Drive SSS A / B (10) A / A (9) Laredo Drive and Saratoga Drive SSS A / A (9) A / A (9) Laredo Drive and East Site Access SSS A / B (10) A / A (9) Laredo Drive and Del Rio Drive SSS A / B (10) A / A (9) SSS – Side-Street-Stop SITE PLAN CONSIDERATIONS A review of the proposed site plan does not indicate any major issues. However, the following items are offered for further consideration between the City and / or project team. • Locate signage and landscaping to avoid creating any sight distance issues. • Review truck maneuverability to limit potential internal circulation conflicts. • Install appropriate internal traffic controls (i.e., stop signs, etc.) per coordination with City staff. CONCLUSIONS Based on the findings of the study, the following conclusions are offered for consideration. 1) There are no existing intersection crash frequency or severity issues within the study area. 2) All study intersections and approaches operate at an acceptable LOS B or better during the typical weekday a.m. and p.m. peak hours. 3) The proposed development is a 59-unit market-rate apartment, which is immediately south of the existing 18-unit apartment complex. 4) Traffic forecasts were developed for year 2028 build conditions, which includes a one (1) percent annual background growth rate and trip generation from the proposed development; the proposed development is estimated to generate 41 a.m. peak hour (10 in / 31 out), 46 p.m. peak hour (29 in / 17 out), and 454 daily (227 in / 227 out) trips. 5) Results of the year 2028 build capacity analysis indicate that all study intersections and approaches are expected to continue to operate at an acceptable LOS B or better during the typical weekday a.m. and p.m. peak hours; no operational issues are expected because of the proposed development from an intersection capacity perspective. 6) No significant site plan related issues were identified, although the items noted above are offered for further consideration by the City and / or project team.