Multilane Roundabout Design FDOT ICE

Roundabout Fundamentals and Intersection Control Evaluation Session 3: Multilane Roundabout Design FDOT ICE

December 16, 2020

SESSION 3: Multilane Roundabout Design/FDOT ICE

Agenda • Multilane Design • Pedestrian and Bicycle Accommodations • Introduction to FDOT ICE

2 SESSION 3: Multilane Roundabout Design/FDOT ICE Multilane Roundabouts • Principles and design process described previously apply to multilane roundabouts but in a more complex way • Multiple traffic streams may enter, circulate through, and exit the roundabout side-by-side • Designer needs to consider how these traffic streams interact with each other

SESSION 3: Multilane Roundabout Design/FDOT ICE Multilane Roundabouts • Geometry should provide adequate alignment and establish appropriate lane configurations for vehicles in adjacent entry lanes to be able to negotiate the roundabout geometry without competing for the same space 9 If not, operational and/or safety deficiencies may occur

Google Earth 4 SESSION 3: Multilane Roundabout Design/FDOT ICE Multilane Roundabouts • Balancing capacity, safety, property impacts, and costs become more difficult with multilane roundabout designs • Geometry, pavement markings, and signing must be designed together to create a comprehensive system to guide and regulate road users who are traversing roundabouts

Google Earth 5

SESSION 3: Multilane Roundabout Design/FDOT ICE Multilane Roundabouts • Additional key considerations for all multilane roundabouts: ¾Lane arrangements to allow drivers to select the appropriate lane on entry and navigate through the roundabout without changing lanes ¾Alignment of vehicles at the entrance line into the correct lane within the circulatory roadway ¾Accommodation of side-by-side vehicles through the roundabout ¾Alignment of legs to prevent exiting-circulating conflicts Google Earth ¾Accommodations for all travel modes

6 SESSION 3: Multilane Roundabout Design/FDOT ICE Lane Arrangement • Ensure that the design provides the appropriate number of lanes within the circulatory roadway and on each exit to ensure lane continuity • Movements assigned to each entering lane are key to the overall design • Pavement markings are integral to the preliminary design process

SESSION 3: Multilane Roundabout Design/FDOT ICE Inscribed Circle Diameter (ICD)

• Single-lane roundabouts • Largely dependent upon the turning requirements of the design vehicle

• Multilane roundabouts • Deflection/speed control • Adequate alignment of the natural vehicle paths • Accommodating design vehicle

NCHRP 672 EXHIBIT 6-2

8 SESSION 3: Multilane Roundabout Design/FDOT ICE Inscribed Circle Diameter (ICD) For initial section of ICD, the design vehicle and context of location should be taken into consideration • Urban location • Typically lower speeds with right-of-way constraints • Rural location • Typically higher speeds with larger vehicles

Roundabout Type Typical Inscribed Circle Diameter

Single-lane 120 – 160 ft Multilane (2-lane entry) 160 – 200 ft

SESSION 3: Multilane Roundabout Design/FDOT ICE Entry Width • Required width is dependent upon the number of lanes and the design vehicle • Typical width for a two-lane entry ranges from 24 to 30 ft • Typical widths for individual lanes at entry range from 12 to 15 ft Google Earth • Typical widths with painted gores: ¾ Entry lanes = 11 to 12 ft ¾ Gore = 4 to 6 ft Use painted gores when providing in-lane truck accommodations!

Google Earth 10 SESSION 3: Multilane Roundabout Design/FDOT ICE Entry Design • The entry curvature should balance the competing objectives of: 9 Speed control 9 Design vehicle accommodations 9 Adequate alignment of natural paths 9 Need for appropriate sight lines • Requires several design iterations to identify the appropriate roundabout size, location, and approach of alignments Google Earth • Multilane entry radii commonly 75 to 110 feet

SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap • Designing multilane roundabouts is significantly more complex than single-lane roundabouts due to the additional conflicts present with multiple traffic streams in adjacent lanes: 9 Entering 9 Circulating 9 Exiting • The natural path of a vehicle is the path it will take based on the speed and orientation imposed by the roundabout geometry

12 SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

NCHRP 672 • Path overlap occurs when the natural EXHIBIT 6-28 paths of vehicles in adjacent lanes overlap or cross one another • The entry design should align vehicles into the appropriate lane within the circulatory roadway • A good design balances entry speed and path alignment • Common on entries, but also can occur on exits

SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

NCHRP 672 14 EXHIBIT 6-29 SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

NYSDOT 15

SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

NYSDOT 16 SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

17 Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

Not Just on Entries

18 SESSION 3: Multilane Roundabout Design/FDOT ICE Path Overlap

19 Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Checking Path Overlap

WisDOT FDM Figure 30.17 Method for checking path overlap 20 SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations • Considerations should be made for both tracking on the entry/exit and within the circulatory roadway • Percentage of trucks and lane utilization is an important consideration • Frequency of a specific design vehicle is also an important consideration • Determine whether the design will allow trucks to use two lanes or accommodate them to stay within their own lane

SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations Case 1 Design • Single lane line dividing the entry lanes • Trucks encroach on adjacent lanes on entry and when circulating and exiting

WisDOT FDM 11-26 22 Figure 30.4 SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations Case 2 Design • Wider entry with gore marking • Trucks stay in lane on entry • Trucks encroach on adjacent lanes when circulating and exiting

WisDOT FDM 11-26 Figure 30.5 23

SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations Case 3 Design • Wider entry with gore marking • Typically larger circle with wider circulatory roadway • Trucks stay in lane on entry, circulating, and exiting

WisDOT FDM 11-26, Figure 30.6 24 SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations Case 2 and 3 typically have a painted gore area provided between lanes on the approach

SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations Outside lane is typically wider than the inside lane

12’-15’ 14’-18’+

Google Earth 26 SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations (FDOT policy)

• Provide adequate pavement area for the simultaneous passage of the design vehicle and a passenger vehicle through the roundabout and for turning movements • Design vehicle swept paths must stay within the travel lanes without encroaching on the inside and outside gutters • Provide a minimum of 18-inches of clearance between curb faces and the outside edge of the design vehicles tire track

SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations (FDOT policy) • Truck trailer is permitted to mount the RA curb and use the truck apron.

28 SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations (FDOT policy) • Develop swept path diagrams for all turning movements in the following combinations: ¾Design vehicle in the outside lane and passenger vehicle in the inside lane ¾Design vehicle in the inside lane and passenger vehicle in the outside lane • When truck volume is very low, consider allowing the design vehicle to command both lanes (Case 1 design)

SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations (FDOT policy) • Acceptable for the design vehicle path to encroach into the adjacent travel lane within the circulatory roadway • Need to provide sufficient space for the passenger vehicle plus 2 feet of clearance between the two vehicles

30 SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations Width of gore marking is determined by the entry lane widths and swept paths of design vehicle

Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Design Vehicle Accommodations

Google Earth Only provide extra width where needed! 32 SESSION 3: Multilane Roundabout Design/FDOT ICE Circulatory Roadway Width • Usually governed by the type of vehicles that need to be accommodated adjacent to one another • Outside lane typically larger ¾ They don’t have to be 15’/15’ ¾ Provides additional space for larger vehicles ¾ Improves entry and exit path tangents

14’-18’

12’-15’

Google Maps Google Maps 33

SESSION 3: Multilane Roundabout Design/FDOT ICE Circulatory Roadway Width • Does not need to remain constant! • Provide only the minimum width necessary to serve the required lane configuration ¾ Major movement may have 2 lanes circulating 2 ¾ Minor movement may only have 1 11 lane circulating

NCHRP 672 34 EXHIBIT 6-26 SESSION 3: Multilane Roundabout Design/FDOT ICE Spirals • Spiral transitions lead drivers into the appropriate lane for their desired exit • Enable vehicles to reach their intended exit without being trapped or needing to change lanes • More effective on larger circles where spiral curves are longer • Avoid the use of spiraled designs unless it’s clearly warranted by traffic Google Earth

35 Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Spirals

FDM Figure 213.5.1 36 SESSION 3: Multilane Roundabout Design/FDOT ICE Spirals • Two semi-circles with different diameters

Google Earth 37

SESSION 3: Multilane Roundabout Design/FDOT ICE Spirals • A spiral should be developed from the central island with curb and gutter!

Google Earth 38 SESSION 3: Multilane Roundabout Design/FDOT ICE Spirals

Google Earth 39 Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Exit Design • As with the entries, the design of exit curvature is more complex at multilane roundabouts • Conflicts can occur between exiting and circulating vehicles if appropriate lane assignments are not provided • Exit radii are usually larger than the entry radii and are typically used to promote good vehicle path alignment • Balanced by the need to maintain slow speeds through the pedestrian crossing on exit

40 SESSION 3: Multilane Roundabout Design/FDOT ICE Curvilinear Exit Design

Google Earth 41

SESSION 3: Multilane Roundabout Design/FDOT ICE Large Radius Exit Design

42 Google Maps SESSION 3: Multilane Roundabout Design/FDOT ICE Exit Design • Highly curved exits may shadow pedestrians from multilane exiting traffic

SESSION 3: Multilane Roundabout Design/FDOT ICE Exit Design • Highly curved exits may also have path overlap

44 SESSION 3: Multilane Roundabout Design/FDOT ICE Exit Tapers • Tapering the number of lanes on an exit from 2 lanes to 1 lane allows for additional capacity without excessive mid-block widening • Roundabouts continuous flow typically results in less saturated traffic streams exiting • Speeds are much slower exiting roundabouts which eliminates the need for a long parallel section downstream of an exit

Google Earth 45

SESSION 3: Multilane Roundabout Design/FDOT ICE Exit Tapers • Design exit tapers based on the anticipated in lane exiting speed, not the fastest path (15 to 25 mph)

WisDOT FDM Figure 30.9

¾ The farther the full lane widths are extended downstream, the higher the speeds and potential for a longer merge taper 46 SESSION 3: Multilane Roundabout Design/FDOT ICE Exit Tapers

47 Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations • Wherever possible, sidewalks at roundabouts should be set back from the edge of the circulatory roadway • Landscape strips provide many benefits: ¾ Increased comfort for pedestrians ¾ Buffer for the overhang of large vehicles ¾ Discourages pedestrians from crossing to the center island or cutting across the circulatory roadway ¾ Helps guide pedestrians with vision impairments to the designated crosswalks

48 NCHRP 672 EXHIBIT 6-63 SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations • Recommended sidewalk width is 6-feet, 5-feet minimum but wider sidewalks may be warranted in areas with heavy pedestrian volumes • Crosswalk marking should be installed on all approaches • Walkway through the splitter island should be cut through instead of ramped

49 Google Earth

SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations • Minimum width within the pedestrian refuge area is 6-feet, desirable is 8-feet, (face to face) • The minimum crosswalk width in the splitter island is 10-feet

NCHRP 672 • Locate the pedestrian EXHIBIT 6-12 crossing one car length or approximately 20-feet upstream from the yield line

50 SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations • Crosswalk alignment options

Recommended

NCHRP 672 51 EXHIBIT 6-66

SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Angled/Perpendicular Pedestrian Crossing

Google Earth 52 SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Straight Pedestrian Crossing

SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Pedestrian Facilities (FDOT Policy) • When there are existing or planned pedestrian facilities, the following requirements apply: i. Sidewalk widths in accordance with FDM 222, or consistent with approach sidewalk widths ii. When bicycle ramps are provided, the desired sidewalk width is 10 feet, but not less than 8 feet iii. 5-foot setback from back of curb to sidewalk is desired • Typically not less than 2 feet

54 SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Pedestrian Facilities (FDOT Policy)

iv. Provide crosswalks at every approach leg • Provide curb ramps and detectible warning surfaces consistent with FDM 222 and Standard Plans, Index 522-002 • Orient crosswalks perpendicular to the roadway • Minimum 6-foot wide and 10-foot-long pedestrian refuge area within the splitter islands • Locate crosswalk 20 feet from the outside edge of the circulatory roadway • Provide pedestrian crosswalk lighting in accordance with FDM 231

SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Rectangular Rapid Flashing Beacon (RRFB)

56 Dr. Bastian Schroeder SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Pedestrian Hybrid Beacon (HAWK Signal)

Farmington, MI 57 Dr. Bastian Schroeder

SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations Pedestrian Hybrid Beacon (HAWK Signal)

Google Earth

58 SESSION 3: Multilane Roundabout Design/FDOT ICE Pedestrian Design Considerations

SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations • Bicyclist approaching a roundabout may merge into the general travel lanes and navigate the roundabout as a vehicle or exit the roadway by way of a ramp and ride on a wide sidewalk

Google Earth

60 SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations • Bicycle lanes should not be provided through the roundabout • Terminated bicycle lanes upstream of the entrance line • Required for multilane roundabouts • Optional for single-lane roundabouts

Google Earth 61

SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations • Where bicycle ramps are provided, the sidewalk width between the bicycle ramps is typically 10-feet (8-foot minimum)

Google Earth

62 SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations

FDM Exhibit 213-1 63

SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations • When a utility strip of at least 3 feet is present

ANGLED BICYCLE RAMP

FDM Figure 213.8.1 64 SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations • Sidewalk adjacent to or very near the back of curb

STRAIGHT BICYCLE RAMP

FDM Figure 213.8.2 65

SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations • Place directional indicator at the top of the bicycle ramp to provide a tactile cue for visually impaired pedestrians to continue down the sidewalk • Do not place detectable warning surfaces on the bicycle ramp

66 SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations

SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations

68 SESSION 3: Multilane Roundabout Design/FDOT ICE Bicycle Design Considerations

SESSION 3: Multilane Roundabout Design/FDOT ICE Additional design details that can impact safety • Sight distance/Visibility • Landscaping • Lighting • Signing • Pavement markings

70 SESSION 3: Multilane Roundabout Design/FDOT ICE Intersection Control Evaluation (ICE) • What is ICE? • Why ICE in Florida? • ICE process overview

SESSION 3: Multilane Roundabout Design/FDOT ICE What is ICE? • Intersection Control Evaluation (ICE) is a data-driven, performance-based framework and approach used to objectively screen alternatives and identify an optimal geometric and control solution for an intersection. • Utilizing ICE policies and procedures to evaluate and select the geometry and control for an intersection offers many potential benefits to road agencies and the traveling public, including: • Implementation of safer, more balanced and more cost-effective solutions. • Consistent documentation that improves the transparency of transportation decisions. • Increased awareness of innovative intersection solutions and emphasis on objective performance metrics for consistent comparisons. • The opportunity to consolidate and streamline existing intersection-related policies and procedures, including access or encroachment approvals, new traffic signal requests, and impact studies for development. 72 SESSION 3: Multilane Roundabout Design/FDOT ICE What is ICE? The ICE process is typically conducted in two stages: • A "Stage 1 – Scoping" step to determine the short list of all possible alternatives that merit further consideration and analysis because they meet project needs and are practical to pursue. • A "Stage 2 – Alternative Selection" step to determine the preferred alternative based on more detailed evaluations conducted during typical preliminary engineering activities.

SESSION 3: Multilane Roundabout Design/FDOT ICE Why ICE in Florida? • Intersection choices have historically been stop control, signalization and recently roundabouts • Raise awareness and increase use of alternative intersections • Consider context classifications, safety, and all road users • Quantitative analysis to select intersection control types • FDOT Developed ICE Manual and Tools • ICE Manual released Nov. 1, 2017 • Spreadsheet tools developed to support safety, operations and benefit-cost analyses

74 SESSION 3: Multilane Roundabout Design/FDOT ICE Available ICE Resources

http://www.fdot.gov/traffic/TrafficServices/Intersection_Operations.shtm

SESSION 3: Multilane Roundabout Design/FDOT ICE ICE Purpose • Consistently consider multiple context-sensitive control strategies when planning a new or modified intersection through… • Informed decision-making considering • purpose and need, context classification, safe travel facilities for all road users, with the overall best value • Select a context-sensitive control strategy considering • the goals and needs of the community and all road users • Measure the control strategy’s value using • performance-based criteria • Promotes thoughtful consideration of alternative intersection types through quantitative analysis

76 SESSION 3: Multilane Roundabout Design/FDOT ICE ICE Project Applicability Check

ICE is REQUIRED when:

• New signalization is proposed • Major reconstruction of existing signalized intersection is proposed • Adding exclusive left turns, adding intersection legs • Conversion of a directional or bi-directional median opening to a full median opening is proposed • Driveway/Connection permit applications for Category E, F, G • District Design Engineer (DDE) and District Traffic Operations Engineer (DTOE) consider an ICE a good fit for the project

SESSION 3: Multilane Roundabout Design/FDOT ICE ICE Project Applicability Check

ICE is NOT REQUIRED when:

• Work does not include substantive proposed changes to intersection • Mill and resurface pavement; changing full median opening to directional median opening • Minor intersection operational improvements • Adding right turn lane or signal phasing changes or equipment upgrades • Encouraged for local roadways, not required • Recommended for ramp terminal intersections (stop control, signalized, or yield), not required 78 SESSION 3: Multilane Roundabout Design/FDOT ICE ICE Stages

SPICE is used in both: Stage 1 and Stage 2 analyses

SESSION 3: Multilane Roundabout Design/FDOT ICE ICE Stages

80 SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 1 – ICE Process Overview

SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 1 – CAP-X Tool • Capacity Analysis for Planning of Junctions (CAP-X) • FHWA/FDOT tool for planning- Capacity Analysis for Planning of Junctions Dynamic Results Summary level capacity assessment No Overall V/C Multimodal Pedestrian Bicycle Transit TYPE OF INTERSECTION V/C Ranking Score Accommodations Accommodations Accommodations • Initial operational screening of Ratio intersection control alternatives Partial Displaced Left Turn N-S 0.42 1 4.8 Fair Fair Good Displaced Left Turn 0.42 1 4.8 Fair Fair Good Signalized Restricted Crossing U- 0.54 3 6.3 Good Good Fair • Conducts critical movement Turn N-S analysis (CMA) to gauge the Traffic Signal 0.58 4 4.8 Fair Fair Good potential performance Quadrant Roadway N-W 0.60 5 4.4 Fair Fair Fair Partial Median U-Turn N-S 0.72 6 6.3 Good Good F a i r • Multimodel accommodations 2 X 2 0.72 7 5.6 Fair Good Good • Qualitative assessment Median U-Turn N-S 0.76 8 6.3 Good Good F a i r

82 SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 1 – SPICE Tool • Safety Performance SPICE Stage 1 Results Intersection Control Evaluations (SPICE) • Performs predictive safety analysis of at- grade intersections • Simultaneous evaluation of multiple alternatives

SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 1 – ICE Form

Control Strategy Evaluation Provide a brief justification as to why each of the following control strategies should be advanced or not. Justification should consider potential environmental impacts. CAP-X Outputs

V/C Ratio Justification Control Weekday AM Weekday PM Multimodal SPICE Strategy to Be Strategy Peak Peak Score Ranking Advanced? Existing intersection control is a traffic signal Two-Way Stop- N/AN/A N/A N/A No Controlled

Existing intersection control is a traffic signal All-Way Stop- N/A N/A N/A N/A No Controlled

Will move forward as the future no-build scenario. Signalized 0.51 0.58 4.8 5 Yes Control

Slightly worse operations than the signal but could Roundabout 0.57 0.72 5.6 4 Yes reduce crashes from the existing signal.

Operational performance decreases when 0.57 (Full) 0.76 (Full) Median U-Turn 6.3 1 No compared to the signal. Construction costs on the 0.50 (Partial) 0.72 (Partial) north leg will reduce feasibility. Operational performance provides a significant RCUT 0.37 0.54 6.3 7 Yes improvement for the AM peak and a slight (Signalized) improvement for the PM peak. Existing intersection control is a traffic signal RCUT N/A N/A N/A N/A No (Unsignalized)

Existing ROW limitations with existing land uses - Jughandle 2 No including Cooter Pond Park.

Existing ROW limitations with existing land uses - Displaced Left- 0.37 (Full) 0.42 (Full) 4.8 3 No including Cooter Pond Park. Only one left turn Turn 0.37 (Partial) 0.42 (Partial) movement is high enough to consider DLT. Existing intersection configuration is 4-leg. Continuous N/A N/A N/A N/A No Green Tee

Existing roadway network on the NW corner could Quadrant 0.48 0.60 4.4 Yes be utilized to improve the operational Roadway performance at the study intersection. Proposed lane configuration prior ICE Evaluation: Signalized 0.48 0.57 4.8 5 Yes Dual SB Left Turn Lanes. Control (Alt) 84 SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 2 – ICE Process Overview

SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 2 – FDOT ICE Tool Overview

86 SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 2 – FDOT ICE Tool • Tool for financial analysis of intersection alternatives • Needed inputs for life-cycle cost analysis Safety - SPICE Vehicular delay – SYNCHRO, VISSIM, HCS, SIDRA, etc. Design, construction, right-of- way, and operating costs • Conducts benefit-cost / net present value analysis • Flexible enough to accommodate all intersection alternatives 87

SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 2 – ICE Form

Control Strategy Evaluation Summary

Control Strategy Evaluation Provide a brief justification as to why each of the following is either viable or not viable. If a single control strategy is recommended, select it as the only strategy to be advanced. Strategy to be Control Strategy Advanced? Justification An additional southbound left turn lane has already been identified as a needed improvement Signalized Control No at intersection.

Alternative provides the highest Benefit-Cost ratio as well as the best Net Present Value. It is Roundabout Yes expected to have the best operational performance and the lowest injury/fatal predicted crashes. Alternative has a negative B/C ratio and NPV. ROW impacts on the north leg to RCUT (Signalized) No accommodate the U-Turn lanes make the alternative less feasible.

Potential ROW impacts to Walgreens and associated costs with alternative yield a negative Quadrant Roadway No B/C ratio and NPV.

Alternative provides the second-best B/C and NPV from the alternative comparison. Signalized Control (Alt) No

88 SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 2 – ICE Form

Resolution To be filled out by FDOT District Traffic Operations Engineer and District Design Engineer Project Determination Identified Control Strategy Approved

Comments

DTOE Name Signature Date

DDE Name Signature Date

SESSION 3: Multilane Roundabout Design/FDOT ICE Stage 3 – ICE Process Overview (If needed)

90 SESSION 3: Multilane Roundabout Design/FDOT ICE

Send follow-up questions to: [email protected]

Kevin Kuhlow, PE [email protected] 608.443.1210

Roundabout Fundamentals and Intersection Control Evaluation Session 3: Multilane Roundabout Design FDOT ICE

December 16, 2020