Considerations in the Review and Approval of a Driveway in Your Jurisdiction

Considerations in the Review and Approval of a Driveway in Your Jurisdiction So, are you the person at your agency who reviews and approves new driveways? Or, perhaps you are part of the TEAM of people that that does this. What specifically do you look for when reviewing the plans for a new driveway; or an access scheme for a big, new private development, like a shopping center or an apartment complex? And who else do you communicate with at your agency about this new driveway? Let s take a look at some information from chapters 8 and 10 of the Transportation Research Board s (TRB) Access Management Application Guidelines (AMAG) 1, for some useful guidance regarding the many considerations that are a necessary part of the review and approval process for new driveway proposals. DEFINITION Driveways are private roads that provide access (both ingress and egress) between a public way and abutting properties and any facilities on those properties. When roadway designers use the term driveway, they are often referring to just a part of a driveway: the area where, or near to where, the driveway intersects the public roadway. That definition is employed here. The geometric design of driveways involves the establishment of the alignment and dimensions of the plan, profile, cross section, and other elements to be constructed in conjunction with the driveway. PURPOSE At and near driveway-to-roadway connections, driveway traffic can affect the quality of flow and the safety of bicyclists, motorists, and pedestrians traveling along the through roadway. After decades of observation and experience, roadway designers have realized that to minimize problems created by driveways, they must give adequate attention to the design of driveway geometric elements. The designer should recognize that the connection of a driveway to a through roadway creates an intersection. It is not uncommon to encounter driveways with volumes greater than those on some public roadways. The conflicts that result from the driveway traffic stream can be a source of operational and safety concerns. GUIDANCE: NEEDS AND ISSUES TO CONSIDER DURING THE REVIEW AND APPROVAL PROCESS The team for the National Cooperative Highway Research Program (NCHRP) Project 15-35: Geometric Design of Driveways identified more than 90 elements that can be related to or affect the geometric design of a driveway. Let s P a g e 1 of 10

look at the long list of driveway design factors that are within and outside of the control of the designer, respectively, in Exhibits A and B on the following pages. EXHIBIT A Driveway Geometric Design Factors Within Control of Designer Shared elements or surroundings Illumination Conspicuity (to visually detect the driveway at a distance) Sight obstructions Driveway Width (maximum and minimum: sufficient for pedestrian refuge if very wide) Lanes (number, width) Median in driveway (absence or presence) - Width, Type (raised, flush, depressed), Nose end recessed from edge of through road Cross slope, cross-slope transition runoff Horizontal alignment, curvature Connection depth (throat length) Traffic controls or other potential impediments to inbound traffic (including entry gate) Paving length (applicable with unpaved driveway) On-site turnaround capability (where backing into roadway in undesirable) Driveway edge (edge drop-off, barrier) Space for nonmotorized users (e.g., pedestrian movement parallel to driveway) Driveway border treatments (side clearance, side slope) Vertical profile (Grade (maximum and minimum), Change of grade (grade breaks), Vertical curve design criteria, Vertical clearance (from overhead structures, utility lines) Drainage (separate from intersection drainage) Other special situations (e.g., railroad crossing, bicycle or multiuse path, bridle path) Sidewalk-driveway intersection Sidewalk cross slope (i.e., driveway grade) Path definition (e.g., visual, tactile cues) Crossing length (i.e., driveway width) Angle of intersection with driveway - Flat angle (turn angle < 90 degrees) - Right angle (turn = 90 degrees) - Sharp angle (turn angle > 90 degrees) Orientation of sidewalk to street: sidewalk diverging from, parallel to, or converging with the street P a g e 2 of 10

Grade of sidewalk (i.e., driveway cross slope) Vertical profile of pedestrian route (abrupt elevation change: maximum ¼ in.) Treatment of sidewalk-driveway interface: detectable warnings for the visually impaired (e.g., truncated dome) only at certain locations, including at signalized crossings Design issues for a vehicle turning right into or from a driveway. Roadway-driveway intersection Angle of intersection with street - Flat angle (turn angle < 90 degrees) - Right angle (turn angle = 90 degrees) - Sharp angle (turn angle > 90 degrees) Cross slope of street and shoulder, considered with driveway grade Curb threshold treatment (rolled, vertical lip, counterslope, continuous) Curb termination treatment (abrupt end, drop down, returned) Entry transition - Shape (curve, flare or taper, straight) - Dimensions (radius, flare dimensions) Channelization of right turn - From street into driveway - From driveway into street Channelization in driveway: triangular island to prohibit left turns in and out Channelization in street - Street median prohibits all left turns in and out of driveway - Street median prohibits one but not both left turns Drainage - Continuing the gutter flow - Inlet type and location Clearance from fixed objects and appurtenances Pavement surface deformity (corrugation, potholes) P a g e 3 of 10

Traffic controls (for driveway vehicles) Driveway-roadway intersection control (none, yield, stop, signal) Turn restrictions One-way operation (one-way, Do Not Enter) Markings (pavement, delineators) Other Roadway in the vicinity of the driveway Right-turn lane attributes (absence or presence) - Width - Deceleration, storage length - Entry transition shape - Offset Left-turn lane attributes (absence or presence) - Width - Deceleration, storage length - Entry transition shape - Offset Number of driveways per site - From upstream access connection - From downstream access connection - From bus stop location Shared elements or surrounds EXHIBIT B Driveway Design Factors Generally Outside Control of Designer Land use User and vehicle mix and composition Temporal variation: season, day of week, time of day Weather and weather effects Sidewalk-to-driveway intersection: sidewalk placement adjacent to or offset from the curb or edge Roadway-to-driveway intersection: difference in elevation between roadway surface and abutting property Roadway in vicinity of driveway Width of roadway Lanes (number, width) Lane type (travel, high-occupancy vehicle, bicycle, turn, parking) Cross slope (travel lanes, shoulders) P a g e 4 of 10

Horizontal alignment of roadway Vertical profile of roadway Sight distance restrictions User characteristics: Bicyclist Some driveway design elements. Bicyclist perception-reaction process, time Speed Sight distance need Braking capability User characteristics: Pedestrian Pedestrian perception-reaction process, time Speed Sight distance need Special needs groups - General (children, elderly) - Disability (e.g., mobility, vision) - Legal mandate: people with disabilities User characteristics: vehicle, driver Driver perception-reaction process, time P a g e 5 of 10

Speed Sight distance need Braking capability (limiting) Deceleration characteristics (typical) Vehicle width Vehicle length Vehicle turning radius Vehicle dimensions - Front overhang - Wheelbase - Rear overhang - Ground clearance APPLICATION ISSUES Motorists are not the only users of driveways. Bicyclists and pedestrians sometimes cross or traverse driveways. Each user group has distinct capabilities and objectives that may conflict with those of other user groups. Although accommodating the needs and desires of the different user groups can be challenging, an effective driveway design must balance these needs. When a driveway is designed, identification of the appropriate design vehicle is not always a straightforward matter. For a driveway serving a single-family residence on a local street, the choice of a passenger vehicle is fairly clear-cut. On the other hand, for small- and medium-sized commercial tracts, to what extent should the design accommodate infrequent large delivery vehicles? Fact Sheet 3 Design Controls in Context Sensitive Solutions 2 distinguishes between a design vehicle that must be accommodated on a regular basis and a control vehicle that uses a facility infrequently. For a given situation, if certain larger vehicles seldom traverse the driveway, then perhaps infrequent encroachments into other traffic lanes could be tolerated. There is no clear-cut guidance for determining what constitutes infrequent use. In many environments, a substantial proportion of the driveway lies outside of the right-of-way of the public roadway. Even so, traffic that occurs within the privately-owned portion of a driveway can affect traffic on public roadways, bike facilities, and sidewalks. The ability of the roadway designer to address the design of elements that physically lie within a private site will be enhanced through communication, cooperation, and coordination with planning, zoning, and building inspection officials. Laws, administrative rules, or ordinances may need to be enacted before a public agency can legally enforce provisions on private property. WHY YOUR AGENCY NEEDS A DRIVEWAY PERMITTING PROCESS A successful driveway permitting process brings about this necessary communication, cooperation, and coordination with the other departments within P a g e 6 of 10

your agency; or even neighboring agencies. The permitting of access is the tool employed by state and local agencies to apply access management standards. Well-organized and effective permitting processes, together with well-trained personnel, are keys to a sound access management program. A driveway permit, (or access permit), is a legal document that grants approval to construct and operate a driveway, or other access of a certain design, at a specified location on a given roadway for specific purposes. A relationship exists between the issuing of the permit and the comprehensive planning of land use to verify acceptable and consistent growth and development. The increase in land use density, development pressure, intensification of activities, and infilling in metropolitan areas have all affected the traffic on urban and suburban roadways and highways. The increasing driveway demands and resulting conflicts necessitate a rigorous driveway regulation program to enable access to abutting properties. Driveways may create safety problems on the main arterials that are not addressed through traditional planning. Local governments typically control the permits to access roadways under their jurisdiction as part of the site plan review process, or sometimes during the land rezoning process. This control is an opportunity for agencies to ensure that the proposed site design is adequate. For example, on-site parking and associated turn movements should not interfere with motorists exiting the roadway, as shown in Figure 1 (below). A possible solution to alleviate delays to such motorists is shown in Figure 2. APPLICATION ISSUES The permitting process attempts to introduce uniform procedures, conform to P a g e 7 of 10

standards, provide consistent driveway design and location decisions, and assure that the review and receipt of approval are timely. PERMITTING PROCESS STEPS The steps in the permitting process include: the initial inquiry, determination of the permit requirements, submittal of the permit application, review by the permitting agency, approval or denial by the agency, and the action taken. PERMITTING PROCESSES INCLUDE SEVERAL TYPES OF PERMITS Temporary permit: an approval for access with a specified time limit. The permit automatically terminates at a specified date. Restricted use permit: an approval for access that is not open to the general public. This access is typically gated and locked. Change of use permit: an approval for access when on-site redevelopment results in additional traffic to the roadway system or a change in the character of the traffic using the access. Construction permit: an approval to allow only the construction of an access to the public roadway. Use permit: an approval to an adjacent property owner to provide access to the roadway system. The use permit typically includes conditions as to the use and maintenance obligations for the access. Agencies generally reserve the right to review, modify, or remove the existing permit for unsafe conditions or impaired traffic operations. SAFETY AND OPERATIONAL PERSPECTIVES Safety should be considered whenever a new driveway is proposed. Analysis and review should reveal potential safety issues with a specific driveway and may result in mitigation measures such as limitations on specific turning movements and driveway design. Permits can be tied to safety performance on a roadway adjacent to a driveway. Changes to permitted designs, location, and strategies can be made in response to safety performance while balancing against the equity to the land uses served by the driveway. Vehicle operations must be considered when an application for a driveway is reviewed. A level of service acceptable for the corridor type and region should be provided. Pedestrians, bicycles, and buses. The safety and operational impacts on pedestrians, cyclists, and transit should be explicitly considered when an application for a driveway is reviewed. Locations with high pedestrian volumes, for example, should minimize driveway width and frequency. Heavy vehicles. Agencies should assess the type, size, and number of trucks that would use the driveway and should design for or accommodate P a g e 8 of 10

these vehicles without undue impact to the traffic stream when practical. Where there are high pedestrian volumes and the site requires deliveries by large trucks, staff should work with the developer to establish time periods for deliveries to minimize interaction between pedestrians and trucks. EVALUATION TECHNIQUES The analysis and review of the requested driveway application would be undertaken to meet the access management policies and standards for your jurisdiction. Typically, when the standards cannot be met, a reasonable solution that results in movement toward the access management standards may be considered an improvement. This solution may be achieved through the means of a variance process. Related Content As previously mentioned, this information was taken from chapters 8 and 10 of the Access Management Applications Guidelines (TRB, 2016); however, there is additional content in it that you and/or your staff can read, which is relevant to this topic: Chapter 3: Access Management Categories Chapter 5: Guidelines versus Standards Chapter 6: Legal Authority for Access Management Chapter 7: Establishing Methods or Procedures for Variances and Deviations Chapter 8: Permitting Process and Methods Chapter 10: Driveway Design and Geometrics Chapter 12: Unsignalized Access Spacing And further information can be found in the Access Management Manual (TRB, 2014): Chapter 11: Access Permitting Chapter 13: Driveways and Other Access Connections Chapter 19: Internal and Intergovernmental Coordination An additional resource is NCHRP Report 659: Guide for the Geometric Design of Driveways. Examples of Commercial Driveway Permit application requirements, from the state level of government, may be found at the following links: http://www.fdot.gov/maintenance/d4permitinfo/d4presentations/05%20access%20 Permits.pdf http://www.dot.state.oh.us/districts/d04/planning/permits/documents/commercial %20Driveway%20Permit%20Requirements.pdf P a g e 9 of 10

http://www.dot.state.oh.us/divisions/engineering/roadway/accessmanagement/ Documents/State%20Highway%20Access%20Management%20Manual.pdf 1 The information contained within this RON Update is derived from the Transportation Research Board s (TRB) Access Management Application Guidelines (2016). 2 Fact Sheet 3 Design Controls in Context Sensitive Solutions. ITE, Washington,D.C.,July, 2013. http://contextsensitivesolutions.org/content/reading/ite_factsheet_3 DISCLAIMER: This RON Technical Update is provided for purposes of general information only. This is not a primary technical or legal authority and should not be relied upon as such. Interested persons should refer to the source documents referenced herein. Please note also that information contained in this document could become outdated or obsolete over time. Notes P a g e 10 of 10