R930-6-7. Design Requirements  


Latest version.
  •   (1) General.

      (a) The design requirements presented herein are intended to protect the functional integrity of state highways, maintain and preserve traffic mobility, provide efficient and necessary access, while protecting the public health, safety, and welfare. Designs for access connections to state highways must comply with Department standards and conform to the current MUTCD. A design based on engineering standards and methods that are more exact than those presented in this rule may be allowed if the design meets the purposes of this rule, does not violate standards of this rule, is based on desirable nationally accepted standards, and is determined acceptable to the Department. Local authority standards that are more stringent than those required by this rule may be used only if determined acceptable by the Department.

      (2) General criteria for authorizing conditional access permit approval.

      (a) General criteria. The Department may authorize modified or new access that is in compliance with this rule.

      (b) Reasonable alternate access. When an application is created for access to a state highway with assigned access category 4 through 9, the access may be granted if reasonable alternate access cannot be obtained from the local street or road system. If the proposed access does not meet design or spacing standards, the access shall be denied if the proposed access on the property has reasonable alternate access available to the general street system and a variance request is not approved.

      (i) Reasonable alternate access from a city or county road shall be determined in consultation with the appropriate local authority and the applicant. A determination of reasonable access from a local street or road shall include consideration of the local street or road function, purpose, capacity, operational and safety conditions and opportunities to improve the local street or road.

      (ii) Where a subject property adjoins or has access to a lesser function road or an internal street system or by way of dedicated rights-of-way or easements, such access will be considered a reasonable alternate access and any access to the state highway will be considered an additional access.

      (iii) Direct access to the state highway may be approved if the alternative local access will create, in the determination of the Department, a significant operational or safety problem at the alternative location and the direct access to the state highway will not create a safety issue or operational impairment to the highway.

      (c) Parcel division. No additional access rights may accrue upon the splitting or dividing of existing parcels of land or contiguous parcels under or previously under the same ownership or controlling interest.

      (d) Signalized intersections. The Department shall give preference to public ways that meet or may be reasonably expected to meet signal warrants in the foreseeable future.

      (e) Category 1. For highways and corresponding facilities with Category 1 designations, any new access or modification of existing access shall meet freeway/interstate design practices and Department and FHWA standards. They must also receive FHWA and Department approval when the Interstate Highway system is involved.

      (i) All private direct access to Category 1 highways, access ramps, and structures is strictly prohibited unless specifically authorized for official temporary highway construction purposes under Department contract and must receive approval from FHWA and the Department when the Interstate Highway system is involved.

      (ii) Public access to a Category 1 facility shall only be provided by means of interchanges properly spaced, located, and designed in accordance with Department and FHWA standards and regulations.

      (iii) Any new access or modification of existing access to Category 1 facilities shall separate all opposing traffic movements by physical constraints such as grade separations and non-traversable median separators.

      (iv) A new interchange or, in the determination of the Department, a significant modification to an interchange on a Category 1 facility that is part of the Interstate Highway system requires the preparation of analyses and reports that meet current FHWA and Department requirements.

      (f) Category 2 and 3. For highways with Category 2 or 3 designations, access may be allowed by means of interchanges or public street intersections. Public street access to Category 3 highways shall be signalized.

      (i) The Department may allow modifications to an existing private point of access abutting a Category 2 or 3 highway including relocation of the point of access within the limits of the property, if such modification or change will benefit the operation and safety of the highway, bring the access level of the highway into greater conformance with the access category, or be in the interest of public health, safety, and welfare.

      (ii) Any direct private access approved for Category 2 or 3 highways shall be for right turns only and shall be closed when reasonable alternate access is available or based on additional criteria defined by the Department in the conditional access permit.

      (g) Category 4 through 9. For highways with Category 4 through 9 designations, direct access may be approved if the alternative local access would create, in the determination of the Department, a significant operational or safety problem at the alternative location and the direct access to the state highway does not create an operational or safety problem for the state highway.

      (h) Category 10. For highways with Category 10 designations, direct access shall be provided only by means of public street intersections.

      (i) All private direct access to Category 10 highways is strictly prohibited unless specifically authorized for official temporary highway construction or utility maintenance and operations purposes under Department contract.

      (ii) Spacing between ramps and adjacent intersections shall accommodate weaving movements and storage requirements to ensure smooth and safe operations for the frontage road.

      (iii) No access shall be allowed between an exit ramp and its downstream cross-street intersection or between an entrance ramp and its upstream cross-street intersection.

      (iv) No access shall be approved within 100 feet of the intersection of freeway ramp and one-way frontage road.

      (3) Access placement requirements.

      (a) Spacing requirements. Table 1 summarizes the minimum required signal spacing, street spacing, driveway spacing, and interchange crossroad access spacing for corresponding state highway access categories.


    TABLE 1

    State Highway Access Management Spacing Standards


    Category Minimum Minimum Minimum Minimum Interchange to

              Signal Street Driveway Crossroad Access Spacing

              Spacing Spacing Spacing to 1st to 1st from last

              (feet) (feet) (feet) Right-in Inter- Right-in

                                        Right-out section Right-out

                                        Driveway (feet) Driveway

                                        (feet) (feet)

    1 (I) N/A N/A N/A n-a n-a n-a

    2 (S-R) 5,280 1,000 1,000 1,320 1,320 1,320

    3 (S-U) 2,640 N/A N/A 1,320 1,320 1,320

    4 (R-S) 2,640 660 500 660 1,320 500

    5 (R-PU) 2,640 660 350 660 1,320 500

    6 (R-U) 1,320 350 200 500 1,320 500

    7 (C-R) 1,320 300 150 n-a n-a n-a

    8 (C-U) 1,320 300 150 n-a n-a n-a

    9 (O) 1,320 300 150 n-a n-a n-a

    10 (F-FR) 1,320 660 N/A n-a n-a n-a


    "N/A" means not allowed

    "n-a" means not applicable


      (i) Signal spacing. Signal spacing addresses the uniformity and frequency of signalized intersections along a highway and one of the most important access management techniques. Signal spacing generally governs the performance of urban and suburban highways. Signals that are closely or irregularly spaced bring about increases in crashes, stops, delay, fuel consumption, and vehicle emissions. Long and uniform signal spacing allows for more efficient progression through a corridor and provides for the implementation of a more efficient traffic control system to accommodate variations in peak and off-peak period traffic flows. Signal spacing shall be as defined in this rule or as deemed necessary by the Department for the safe operation, capacity, signal progression, and proper design of the signal and adjacent accesses. Preference for the spacing, timing, and operation of a signal shall be given to highways and cross streets of a higher access category or function.

      (ii) Street and driveway spacing. Access connections, including streets and driveways introduce conflicts and friction into the traffic stream of the main highway. Vehicles entering and leaving the main highway often slow the through traffic. The speed differentials between turning and through vehicles increase the potential for crashes. Increasing the distance between intersections and driveways enhances traffic flow and safety by reducing the frequency of conflicts for the main highway and providing greater distances to anticipate and recover from turning maneuvers. Where feasible or required by this rule, accesses must be combined or closed to reduce frequency and increase spacing between accesses. The spacing must also be consistent with current signal progression efficiency and cause no degradation to existing operations.

      (iii) Interchange crossroad access spacing. Freeway and expressway interchanges allow traffic to transition from freeways to arterial or other lower functioning roadways. Interchanges also serve as important focal points of roadside development in urban, suburban, and rural areas. Intersections that are too close to the arterial/freeway interchange ramp termini result in heavy weaving volumes, complex signal operations, frequent accidents, and recurring congestion. Access connections to interchange crossroads shall be sufficiently spaced to allow the smooth transition between the freeway or expressway and intersecting lower functioning roadways. The Department may require applicants to conduct a weaving or speed change lane analysis given unique area conditions. The Department may require applicants to use a distance greater than defined in this rule when said analysis shows that a greater spacing is necessary to provide safe and efficient weaving maneuvers.

      (A) The following elements must be considered in determining minimum interchange crossroad access spacing distances:

      (I) The distance required to weave across the through travel lanes.

      (II) The distance required for transition into left-turn lane(s).

      (III) The distance needed to store left turns with a low likelihood of failure.

      (IV) The distance from the stop line to the centerline of the intersecting road or driveway.

      (B) The minimum interchange to crossroad spacing requirements of Table 1 are based on the following definitions:

      (I) "To 1st right-in right-out driveway," means the distance from the interchange off-ramp gore area (point of widening on the crossroad) to the first right-in right-out driveway intersection.

      (II) "To 1st intersection," means the distance from the interchange off-ramp gore area (point of widening on the crossroad) to the first major intersection.

      (III) "From last right-in right-out driveway," means the distance from the last right-in right-out driveway intersection to the interchange on-ramp gore area (point of widening on the crossroad).

      (b) Emergency access. Emergency access may be approved on state highways with category 2 through 10 designations, where required by local safety regulations, or where the Department has determined exigent circumstances exist. Such direct emergency access may be approved only if it is not feasible to provide the emergency access to a secondary roadway. External requests for emergency access must include a written explanation with references to local standards from the local authority safety official. Emergency access may not be authorized to accommodate general vehicular ingress or egress. The access shall be gated and locked.

      (c) Agricultural access. Agricultural access may be approved on state highways with access to category 2 through 9 designations and where, in the determination of the Department, the property has no other reasonable alternate access. Additional agricultural access to property under the same ownership or controlling interest may be approved if the necessity for such additional access due to topography or ongoing agricultural activities is demonstrated. Agricultural accesses must be kept to the minimum necessary to provide access service. Agricultural access must meet minimum access design and safety standards of this rule. A change in use of the parcel of land serviced by the agricultural access may require that the access be closed. The spacing criteria between accesses contained in this rule may be waived for agricultural access. All such agricultural accesses must meet the sight distance criteria of this rule.

      (d) Access near at-grade railroad crossings. Conditional Access Permits within 250 feet of an at-grade railroad crossing are prohibited unless approved by the Department. Circumstances may exist where greater spacing is required consistent with the appropriate access category spacing. See Utah Administrative Code R930-5 for more information on the process to follow to comply with Department spacing requirements.

      (e) Shared access. Shared access of two or more parcels may be required where a proposed new access or the redesign of an existing access does not meet spacing standards and criteria for the appropriate access category. The access location shall serve as many properties and interests as possible to reduce the need for additional direct access to the state highway.

      (f) Offset placement. Where proposed or redesigned access connections which are offset and not separated by a non-traversable median are to be considered, every effort must be made to align opposing driveways and streets.

      (g) Challenging topography. Where existing topography or other existing conditions make the required access spacing intervals not feasible, the Department may consider topography, established property ownerships, unique physical limitations, unavoidable or pre-existing historical land use patterns, and physical design constraints with a reasonable attempt to achieve the required access spacing. Where there are conflicts within this rule, the more stringent requirement must be met.

      (4) Access design requirements.

      (a) Sight distance. Access points must be located and designed to provide adequate sight distance along the state highway and the access.

      (i) Access design must meet AASHTO sight distance guidelines and Department standards.

      (ii) Potentially obstructing objects, including but not limited to, advertising signs, structures, trees, and bushes must be designed, placed, and maintained to meet sight distance requirements for vehicles using the access.

      (iii) Modifications to the existing highway may be required for access points with less than the required minimum sight distance. Modifications may include, but are not limited to, changes to horizontal or vertical alignments, addition of acceleration or deceleration lanes, roadway relocation, use or creation of other general street system facilities, or other modifications as required by the Department.

      (b) Access width. Access width shall be designed and constructed to properly accommodate the anticipated traffic volumes, lane geometries, and vehicle characteristics of both the access and the adjoining highway.

      (i) Minimum and maximum access widths (feet):

      (A) Commercial or industrial land uses:

      (I) Two-way direction use: 25 feet minimum to 50 feet maximum.

      (II) One-way direction use: 16 feet minimum to 30 feet maximum.

      (B) Residential land uses:

      (I) Two-way or one-way direction use: 16 feet minimum to 30 feet maximum.

      (C) Agricultural uses:

      (I) Two-way or one-way direction Use: 16 feet minimum to 32 feet maximum.

      (ii) One-way approaches. The Department may treat adjacent one-way approaches (one-way in, one-way out) as one access when all of the following conditions are met:

      (A) The one-way approaches are divided by a non-traversable median at least four feet wide but no more than 25 feet.

      (B) Signing for the access median is clear and visible.

      (iii) Future public streets. Applications for an access point intended to become a future public street access must consider long-term traffic projections, modal use, and agency standards to determine appropriate access widths.

      (iv) Private openings for limited-access highways. The maximum size of private access openings shall be 16 feet for residences, 32 feet for farms or other areas where large equipment is used, and 50 feet for commercial and industrial areas.

      (c) Access radii. The turning radii of an access must accommodate the turning radius of the largest vehicle using the access on a regular basis.

      (i) Minimum and maximum radii ranges:

      (A) Commercial, industrial, or agricultural land uses:

      (I) Urban areas: 30 feet minimum to 60 feet maximum.

      (II) Rural areas: 20 feet minimum to 60 feet maximum.

      (B) Residential land uses:

      (I) Urban areas: 10 feet minimum to 15 feet maximum.

      (II) Rural areas: 20 feet minimum to 30 feet maximum.

      (ii) Where possible, applicants shall reduce the access radii to improve visual and physical separation of accesses and to reduce pedestrian conflicts by reducing the total access width at the roadway edge (i.e., at the intersection). Access radii shall be no larger than required to accommodate the volume and type of vehicles using the access on a regular basis.

      (iii) Curb cut style driveways are typically required where curbs are present. However, radius curb returns may be used when determined by the Department to be necessary and consistent with existing or planned conditions.

      (iv) Access points intended to become a future public street access may use the design criteria of the local authority and the Department to select appropriate radii, corner and intersection design. Access designs are subject to approval by the Department.

      (d) Driveway profile. Driveways must be designed to minimize slope changes to prevent dragging and must conform to Department standards, including UDOT standard drawings.

      (e) Driveway vertical curves. Driveway vertical curves must be as flat as feasible and at least 20 feet long. To prevent dragging, the following driveway vertical curve designs are prohibited:

      (i) A hump or dip greater than 6 inches within a wheelbase of 10 feet.

      (ii) Crest vertical curves exceeding a 3-inch hump in a 10-foot chord.

      (iii) Sag vertical curves exceeding a 2-inch depression in a 10-foot chord.

      (iv) Rolled gutters crossed by traffic.

      (f) Driveway angle. Driveway angles less than 80 degrees are prohibited. Whenever possible, driveways must provide a right (90-degree) driveway angle.

      (i) Exceptions. For one-directional use driveways with a right-turn entry-only or a right-turn exit-only operation, driveway angles may not be less than 60 degrees. Whenever possible, these one-directional driveways must provide a right (90-degree) driveway angle.

      (g) Access signing. Traffic control devices for accesses that serve the general public must conform to the current MUTCD. Stop or yield signs are required for all street intersections and driveways when warranted by traffic conditions.

      (h) Emergency access. Emergency access features must be designed to accommodate emergency vehicle characteristics appropriate for the development or intended land use and in conformance with the Department driveway standards, including those defined in this rule. However, emergency access widths may be designed to serve one-way traffic and may be less than 16 feet wide.

      (i) Emergency access surfacing must minimize its visibility while still providing sufficient strength.

      (ii) Emergency access must be designed based on the standards of the local emergency services and accommodate emergency vehicles necessary to serve the site.

      (iii) Emergency access must provide a suitable barrier to eliminate non-emergency use. The access must be signed for emergency services only and shall only be opened during emergencies.

      (iv) The access, including but not limited to barriers and signing, shall be maintained by the permittee.

      (v) Emergency access barriers shall not be placed within the state highway right-of-way.

      (i) Other design elements. The Department may require other design elements or features to ensure accesses are designed and constructed in a manner that will encourage proper operations and safety. Additional design elements and features include, but are not limited to, the following:

      (i) Positive barrier. The Department may require access with turn restrictions to provide positive barrier such as a non-traversable median to prevent unauthorized turns. Intersection or driveway islands that channel traffic movements may be required for turn-restricted movements when any of the following apply.

      (A) No restrictive center median is in place or programmed to be constructed.

      (B) When frequent violations of the turn restrictions are anticipated.

      (ii) Parking and site circulation. Accesses must be designed to facilitate turning movements to and from the highway while preventing vehicle queues on the highway.

      (A) Parking or storing vehicles within the state highway right-of-way is prohibited without the prior written consent of the Department. See UDOT Policy 06C-09 - Placement of Angle Parking on State Highways for more information. Roadside businesses must provide sufficient private parking or storage space to handle their corresponding parking needs and not rely upon any parking space within the state highway right-of-way.

      (B) Access may be denied for parking areas that require backing maneuvers onto the state highway, roadway or, right-of-way. Circulation for parking facilities must be arranged to restrict backing onto the state highway and allow vehicles to enter and exit the site in forward drive. This requirement does not apply to residential single unit driveways.

      (C) Accesses that have or are planned to have a gate across it, must be designed so the longest vehicle using the access can clear the highway when the gate is closed. For locations with prohibitive topographical features, applicants must provide a wide shoulder for temporary standing while the gate is operated.

      (D) The Department may require the review of the parking lot and circulation layout and require designs, terms, and conditions necessary to ensure the safe use of the access.

      (iii) Modal considerations. Access designs must provide for the safe and convenient movement of all highway right-of-way users and modes of transportation including but not limited to pedestrians, bicyclists, transit, and the physically challenged. Sidewalks and bike lanes or paths may be required where deemed appropriate by the Department or when required by the local authority.

      (iv) Storm drainage. All new or modified accesses must make provisions for site retention, detention, or accommodation of site originating surface runoff such that no flow of stormwater or spill shall utilize the state highway drainage system unless by prior analysis and agreement in conformity with UDOT Policy 08A-06.

      (A) Applicants must construct all driveways and buffer areas to maintain a positive drainage system within the highway right-of-way and not alter the stability of the roadway sub-grade.

      (B) The Department is not liable for the quality of drainage waters originating at service stations or special industrial processing plants that are directed into irrigation canals through highway drainage system. Such drainage concerns are the subject of separate agreements and permits by the developers and irrigation companies.

      (v) Roadside development lighting equipment. All lighting equipment for the roadside development must be placed outside the highway right-of-way. Directing light beams toward the eyes of approaching drivers on the highway is prohibited.

      (5) State highway design requirements.

      (a) General. This section describes the Department requirements for highway features located within the rights-of-way of any state highway. Highway features include, but are not limited to, traffic signs and street name signs, traffic signals, traffic control equipment, highway lighting, crosswalks, curb and gutter, sidewalks, and pavements. Installation of new features within the highway right-of-way and modifications to existing highway features necessary as part of permitted work must be completed at the expense of the permittee and in accordance with plans approved by the Department. Any damage to existing highway features must be repaired or restored at the expense of the permittee and in accordance with plans approved by the Department. Any work completed within state highway right-of-way must comply with Department standards and conform to the current MUTCD.

      (i) Site specific requirements. For specific sections of state highway, the Department may provide additional requirement details for access design and construction, including but not limited to, pavement thickness and specifications, curb design and specifications, roadway fill design and compaction, testing and inspection, and other specific details.

      (ii) Posted speed. A proposal for access may not presume a lower posted speed limit than currently posted or request a lower speed limit in order to accommodate the access.

      (b) Traffic signals. The installation of permanent traffic control devices, including but not limited to traffic signals is regulated by the MUTCD and Department guidelines and standards.

      (i) Nothing in this rule is intended to require the Department to authorize a traffic signal or other permanent traffic control device.

      (ii) The Department may, at its discretion, complete the installation of permanent traffic control devices. The permittee shall pay for direct costs and labor provided by the Department for the installation and relocation of all traffic control devices within public right-of-way which are directly related to the use or construction of the proved access.

      (iii) Signal location, timing, and operation are not intended to serve or benefit single use or private access connections. Preference to signal location, timing and operation shall be given to highways and cross streets of a higher access category or function.

      (iv) New traffic signals and modifications to existing traffic signals shall be allowed only as approved by the Department. No traffic signal may be authorized without the completion of an analysis that is sealed (stamped) by a Professional Engineer licensed in the State of Utah and meets MUTCD signal warrants and all requirements of the Department. The traffic signal analysis must consider traffic signal system operation, design, construction feasibility, and safety.

      (v) For existing or proposed accesses that meet MUTCD warrants and the Department requirements for signalization, but do not meet the spacing or placement requirements of this rule, the access shall be reconstructed to conform to appropriate design criteria and eliminate or reduce the traffic movements that caused the traffic signal warrant to be met.

      (vi) Where the access may warrant signalization in the future, phasing of the installation may be required.

      (vii) The Department may, at its discretion in consideration of approving access, require design, and operational modifications, restrict one or more turning movements, or deny access.

      (viii) Category 2 and 3. For state highways with Category 2 or 3 designations, signals at intersections with major cross streets or roads of equal importance may be programmed to optimize traffic on both streets equally. Cross-streets of lesser importance need not be optimized equally. Traffic signals must be programmed to allow a desirable highway bandwidth of at least 50 percent. The efficiency of the signal system must be analyzed utilizing traffic volume, capacity, and level of service calculations. The analysis must determine the optimum progression speed under both existing and proposed conditions.

      (ix) Category 4, 5 and 6. For state highways with Category 4, 5, or 6 designations, where it is not feasible to meet one-half mile spacing and where signal progression analysis indicates good progression (40 percent efficiency or better), or does not degrade the existing signal progression, a full movement intersection may be allowed. In such cases, a variance and subsequent traffic study is required. Spacing to nearby intersections must be sufficient to accommodate the future vehicle storage queues for both turning and through movements. The access location must also meet other access spacing, design, and need requirements of this rule.

      (c) Surface. The permittee must appropriately surface driveways and connections between the traveled way and the service area. For accesses adjoining paved highways, the permittee must pave the access surface to the right-of-way line. Pavement materials used within the state highway right-of-way shall meet Department standards and requirements.

      (i) Preservation of new pavement. The Department may not issue permits to cut or excavate on newly constructed, paved, or overlaid state highways. This preservation restriction applies for a period of two years after installation of pavement or overlay. Exceptions to preservation of new pavement restrictions shall be made only in cases of emergency, and only with the approval of the appropriate Department Region Director or designee.

      (d) Median treatments. A raised median or movement channelization may be required.

      (i) Nothing in this rule is intended to require the Department to authorize a left turn movement at any location.

      (ii) Left turn movements may not be approved if a median is already established and the proposed opening of the median does not provide, in the determination of the Department, any significant operational or safety benefits to the general public or will be counter to the purpose of the median construction and the continued function of the highway at the category assigned to it.

      (iii) A median opening may not be allowed if any of the following apply:

      (A) A safety or hazard situation is likely or identified.

      (B) The location is within the functional area of an existing or planned interchange, signalized intersection, or major unsignalized intersection.

      (iv) Category 2 and 3. For state highways with Category 2 or 3 designations, Left turn movement may be approved if all of the following apply:

      (A) Access does not have potential for signalization.

      (B) Travel is circuitous in one direction that exceeds two miles.

      (C) Left turn movement can be designed to the Department's satisfaction that meets all safety, design, and operational standards.

      (v) Category 4, 5, 6, 7 and 8. The following apply for state highways with Category 4, 5, 6, 7 or 8 designations:

      (A) If a restrictive median exists, left turns at unsignalized intersections shall be restricted unless the restriction of these movements will cause a safety or operations problem or cause an out-of-direction movement of greater than one mile (or one-half mile for state highways with Category 6, 7, or 8 designations).

      (B) If a flush or traversable median exists, left turns may be approved unless an operational or safety problem is identified.

      (e) Auxiliary lanes. Auxiliary lanes for state highways must conform to Department Standards, including UDOT standard drawings.

      (i) Auxiliary lanes may be required where any of the following apply:

      (A) An auxiliary lane has been specifically identified and documented necessary to prevent or correct an operational or safety condition that will be associated with traffic imposed by the creation of a new access or an existing access.

      (B) Any of the following apply for an access to an access category 2 or 3 highway:

      (I) A left turn lane with deceleration, storage, and taper lengths is required for any access with a projected peak hour left turn ingress turning volume greater than 5 vehicles per hour.

      (II) A right turn lane with deceleration and taper lengths is required for any access with a projected peak hour right turn ingress turning volume greater than 10 vehicles per hour.

      (III) A right turn lane with acceleration and taper lengths is required for any access with a projected peak hour right turning volume greater than 10 vehicles per hour.

      (IV) A left turn acceleration lane may be required if such a design will be a benefit to the safety and operation of the roadway.

      (V) Left turn acceleration lanes are generally not required where the posted speed is less than 50 mph, the intersection is signalized, or the acceleration lane would interfere with the left turn ingress movements to any other access.

      (C) The following applies for an access to an access category 3 highway:

      (I) Left turn acceleration lanes are generally not required where the posted speed is less than 45 mph, the intersection is signalized, or the acceleration lane would interfere with the left turn ingress movements to any other access.

      (D) The following apply for an access to an access category 4 or 5 highway:

      (I) A left turn deceleration lane with taper and storage length is required for any access with a projected peak hour left ingress turning volume greater than 10 vehicles per hour. The taper length must be included in the required deceleration length.

      (II) A right turn deceleration lane and taper length is required for any access with a projected peak hour right ingress turning volume greater than 25 vehicles per hour. The taper length must be included in the required deceleration length.

      (III) A right turn acceleration lane and taper length is required for any access with a projected peak hour right turning volume greater than 50 vehicles per hour when the posted speed on the highway is greater than 40 mph. The taper length must be included in the required acceleration length. A right turn acceleration lane may also be required at a signalized intersection if a free-right turn is needed to maintain an appropriate level of service for the intersection.

      (IV) Right turn deceleration and acceleration lanes are generally not required on roadways with three or more travel lanes in the direction of the right turn.

      (V) A left turn acceleration lane may be required if it will be a benefit to the safety and operation of the roadway.

      (VI) A left turn acceleration lane is generally not required where the posted speed is less than 45 mph, the intersection is signalized, or the acceleration lane would interfere with the left turn ingress movements to any other access.

      (E) Any of the following apply for an access to an access category 6, 7, 8, or 9 highway.

      (I) A left turn lane with storage length plus taper is required for any access with a projected peak hour left ingress turning volume greater than 25 vehicles per hour. If the posted speed is greater than 40 mph, a deceleration lane and taper is required for any access with a projected peak hour left ingress turning volume greater than 10 vehicles per hour. The taper length must be included in the deceleration length.

      (II) A right turn lane with storage length plus taper is required for any access with a projected peak hour right ingress turning volume greater than 50 vehicles per hour. If the posted speed is greater than 40 mph, a right turn deceleration lane and taper is required for any access with a projected peak hour right ingress turning volume greater than 25 vehicles per hour. The taper length must be included in the deceleration length.

      (F) The following apply for an access to an access category 10 highway:

      (I) Exclusive turning lanes are required for all intersections. At a minimum all street accesses must provide an exclusive right turn lane with a minimum length of 250 feet, exclusive of tapers. Longer storage lengths may be necessary based on traffic analysis. Left turn lane dimensions to be defined through traffic analysis. Taper and deceleration lengths to meet current Department standards for posted speeds.

      (ii) For specifically identified and documented safety and operational reasons, a turn acceleration or deceleration lane may also be required based on any of the following location factors:

      (A) Volume of commercial trucks.

      (B) Influence of nearby access.

      (C) Highway speed and traffic density access volume.

      (D) Existing highway auxiliary lanes close to the access.

      (E) Nearby traffic control devices.

      (F) Available stopping sight distance.

      (G) Topographic and highway design factors.

      (iii) For access locations with high percentage of truck use, the Department may require corresponding auxiliary lanes be built to full length and width and the transition taper length extend beyond the full length.