Florida Department of Transportation District 1 has requested that the interchange of SR 64 at Interstate 75(I-75) be modified. This modification replaces the previously approved 2012 System Interchange Modification Report (SIMR) Recommended Diamond Interchange to a NW Loop Only interchange. The study area along I -75 extends from north of SR 70 to south of US 301, a distance of approximately 7.3 miles, and along SR 64 from 66th St Ct/64th St Ct to Grand Harbour Parkway, a distance of approximately 0.91 miles.
The purpose of this Interchange Modification Report (IMR) is to reevaluate the future traffic operations at the I-75/SR 64 interchange based on the revised population/traffic growth projections and reevaluate the need for the diamond interchange configuration recommended by the Project Development and Environmental (PD&E) study and the System Interchange Modification Report (SIMR). The need for this IMR is to identify the most suitable interchange configuration to meet the demands of future travelers while minimizing project costs and impacts.
A Methodology Letter of Understanding (MLOU) was prepared to document the methodology for the analysis and evaluation for this Interchange Modification Report (IMR). The MLOU was approved by the District Interchange Review Committee, FDOT Systems Planning Office and Federal Highway Administration (FHWA) in March 2014. A signed copy of the MLOU is provided in Appendix A. The following sections summarize the methodology stated in the MLOU.
The adopted 2007 Sarasota/Manatee Counties (SMC) Validation Model and 2035 SMC Cost Feasible Model have been utilized for the purposes of forecasting future travel demand. Other currently approved development plans that may impact the study area were obtained from Manatee County. The recently adopted 2035 SMC Cost Feasible Model was used to perform a sub-area validation for the defined project study area. The sub-area validation meets the requirements of the Florida Standard Urban Transportation Modeling System (FSUTMS) Model Update Task Force. This procedure is also consistent with the recommendations from the Interchange Handbook Technical Resource Document (TRD) 8 – Travel Demand Model Selection. If required, adjustments to the model are made as noted within the Interchange Handbook TRD Section 8.This is also consistent with Section 3.8.2 of 2012 Project Traffic Forecasting Handbook (Figures 3.3 and 3.4) and the FSUTMS-Cube Framework Phase II Model Calibration and Validation Standards dated October 2, 2008.
The travel demand forecasts from the sub-area validated 2035 cost feasible model were extrapolated using growth rates to obtain design year (2040) traffic projections. The growth rates were developed based on comparison of historic trends, 2012 existing traffic counts and forecasted model output volumes.
The interchange modifications recommended in this IMR are intended to provide improved interchange operations at the SR 64 interchange. Additional recommendations enhance the arterial operations of SR 64. The following two alternatives have been developed and analyzed for this IMR, Alternative
1: 2012 SIMR Recommended Diamond Interchange and Alternative
2: NW Loop Only Interchange.
The alternatives were analyzed to assess their effectiveness in meeting the future travel demand of the study area as well as the physical and social impacts, and safety and environmental considerations associated with each alternative.
The I-75/SR 64 interchange (MP 7.076) is approximately 3.6 miles north of the I-75/SR 70 interchange and 3.7 miles south of the I-75/US 301 interchange. The study area along I-75 is from north of the I-75 & SR 70 interchange (MP 3.719) to south of the I-75 & US 301 Interchange (MP 11.012) and along SR 64 from 66th St Ct/64th St Ct (to the west-MP 5.932) to Grand Harbour Parkway (to the east- MP 6.842). The following intersections and segments are included in the study area.
Signalized Intersections (from west to east):
SR 64 & 66th St Ct/64th St Ct
SR 64 & I-75 SB Ramps
SR 64 & I-75 NB Ramps
SR 64 & Grand Harbour Parkway
Roadway Segments (from west/south to east/north):
SR 64 from 66th St Ct/64th St Ct to Grand Harbour Parkway
I-75 south of SR 64
I-75 north of SR 64
The proposed improvements to the interchange will enhance traffic operations on SR 64 and have no adverse impacts to I-75. The proposed interchange will remain inside the existing SR 64 interchange right-of-way thereby eliminating any additional environmental impacts.
Purpose and Need
Download the Purpose and Need (PDF, 82.7KB)
I-75, a north/south facility, is an integral part of the SIS providing for high-speed, high-volume traffic movements within the State. The Project Development Summary Report (PDSR) that was submitted in July 2009 as part of the I- 75 Manatee County PD&E Study from south of University Parkway to north of Moccasin Wallow Road, recommended improvements to the SR 64 interchange. This included modifying its current partial cloverleaf configuration to a diamond interchange, as well as adding additional turn lanes to the ramp terminal intersections. Auxiliary lanes were also recommended both north and south of the SR 64 interchange. The Final I-75 Systems Interchange Modification Report (SIMR) from Laurel Road to North of Moccasin Wallow Road dated May 2012, re-analyzed the I-75/SR 64 interchange and also recommended modifying it from its current partial cloverleaf configuration to a diamond configuration (2012 SIMR Recommended Diamond Interchange) by year 2040. As documented in the PD&E study, the previously adopted 2030 cost feasible model considered an average growth rate of 4.5 percent per year along the intersecting cross streets of I-75. However, based on review of the traffic forecasts from the currently adopted 2035 Sarasota-Manatee Charlotte (SMC) model, the traffic projections are significantly lower than the previous estimates.
The purpose of this IMR is to reevaluate the future traffic operations at the I-75/SR 64 interchange based on the revised population/traffic growth projections and reevaluate the need for the diamond interchange configuration recommended by the PD&E study and the SIMR. The need for this IMR is to identify the most suitable interchange configuration to meet the demands of future travelers while minimizing project costs and impacts.