Iowa Admin. Code r. 761-112.5

Current through Register Vol. 47, No. 6, October 2, 2024

Rule 761-112.5 - Access types and the primary highway category system

This rule manages access connections according to highway function, design, traffic volumes, speed and roadside conditions.

(1)General.

a. The department will assign access categories to all highways according to the descriptions in subrule 112.5(3).

b. There are no minimum or maximum distance criteria for the length of a category assignment.

c. The department may assign a specific category to a segment of highway based on operational needs and to maintain consistency along a specific route.

d. The department will maintain an access category assignment schedule for the highway system.

e. Municipal access categories are for primary highway extensions within municipalities where concurrent jurisdiction applies pursuant to Iowa Code section 306.4(4).

f. For all access categories, access connections should be kept to the minimum necessary to provide reasonable access. A second access to a parcel may be provided only if it meets spacing criteria, internal circulation is not feasible, and there is a necessity for the access.

g. If the category allows type D access, an additional type D access may be granted to a parcel if the necessity due to topography problems or ongoing agricultural activities is demonstrated. A change in use of the parcel of land serviced by the type D access requires a new permit and may require the access be closed if the location will not meet access category requirements for another type.

h. A secondary access for emergency fire services when required by local fire safety regulations may be permitted on all categories except for the categories interstate and freeway (I/F), expressway (E), and municipal expressway (ME) and across controlled access lines. Such emergency access may be permitted only if it is not feasible to provide the emergency access to a secondary roadway. A written explanation with references to local standards from an appropriate government safety official shall be included with the application. The access shall not be open for nonemergency uses and shall be maintained by the permittee as a closed access except during emergencies. Hidden pavement structures are acceptable.

i. Access connections to government parcels will be treated the same as private access types based on volume with the exception of egress access connections used specifically for emergency response services such as fire stations.

(2)Access types. Access connections are distinguished by the following four types of private access based on access connection traffic volume:

a. Type A is a private access connection with traffic volumes equal to or greater than 100 trips in a peak hour. Traffic volume estimates are to be based on a 20-year projection or the build-out of the development, whichever is greater.

b. Type B is a private access connection with traffic volumes between 11 and 99 trips in a peak hour. Traffic volume estimates are to be based on a 20-year projection or the build-out of the development, whichever is greater.

c. Type C is a private access connection with traffic volumes between 1 and 10 trips in a peak hour.

d. Type D is a private access connection with an AADT of less than one per day.

(3)Access categories for highways. Access categories are distinguished as follows:

a. The interstate and freeway (I/F) category applies to highways with full access control. Access to the roadway, when allowed, shall be provided by ramps. Direct access to the main roadway and all ramps is prohibited without exception.

b. The expressway (E) category applies to nonfreeway multilane highways outside municipal boundaries where the department has acquired the associated access rights. No access that has not already been authorized shall be permitted across existing access control lines. An access management plan is required to authorize a new public intersection. No new direct access connections will be permitted for utilities that have not been previously authorized.

c. The rural-600 (R-600) category applies to two-lane and multilane highways outside municipal boundaries that are on the Iowa commercial industrial network as most recently approved by the commission, or are where roadway traffic volume will be equal or greater than 3,000 AADT within 20 years. Access types A, B and C may be permitted where the applicant can prove necessity and the access has a minimum spacing distance of 600 feet from other connections. Access type D must meet sight distance requirements. Private access connections should not be permitted within the functional area of any public intersection. Public intersections should be located at survey section lines when feasible. Each full-movement access connection should serve as many properties and interests as possible to reduce the need for additional direct access to the highway. Preference shall be given to public intersections.

d. The rural safety and need (R-S/N) category applies to two-lane highways outside municipal boundaries that will not exceed 3,000 AADT within 20 years. This category includes frontage roads, service roads and access ways. All private access types may be permitted where the applicant can prove necessity and meet sight and spacing distance requirements. Private access connections should not be permitted within the functional area of any public intersection. Public intersections should be located at land survey section lines when feasible.

e. The municipal expressway (ME) category applies to nonfreeway multilane highways inside municipal boundaries where arterial performance is necessary to provide high mobility and through traffic capacity. In the absence of an access management plan, no private access shall be permitted that has not already been authorized. An access management plan is required to authorize a new public intersection and may only be allowed if the public roadway is adopted by the city. No access shall be permitted across a controlled access line.

f. The municipal-1000 (M-1000) category applies to important regional and intracity highways that are within a municipality. Designation of M-1000 shall include consideration of system continuity and preservation of a high level of mobility and through traffic capacity. The department recommends the installation of restrictive medians between full-movement intersections. Access to an M-1000 may be granted under the following conditions:

(1) All access types are eligible for a full-movement access connection at 1,320 feet (one-quarter mile) locations based on section lines where feasible, and these access connections may be restricted to right-in and right-out turns or directional left-in-only as access volumes increase. A minimum access spacing interval of 1,000 feet should only be permitted if there is a documented necessity. No access connection should be allowed within the functional area of a public intersection.

(2) Each full-movement location should serve as many properties and interests as possible to reduce the need for additional direct access to the highway. Preference shall be given to public intersections.

(3) All access types are eligible for limited movement connections at minimum spacing intervals of 600 feet if a restrictive median is present.

g. The municipal-600 (M-600) category applies to highways within municipalities that have been determined to have a need to maintain a moderate level of mobility and through traffic capacity. Minimum spacing for all access types is 600 feet.

h. The municipal-300 (M-300) category applies to highways within municipalities where a low level of mobility and through traffic capacity is acceptable. Minimum spacing for all access types is 300 feet.

i. The municipal safety and need (M-S/N) category applies to highways within municipalities where motor vehicle mobility and through traffic capacity are low priorities. The granting of access and the determination of access connection locations shall be based only on safety and need.

(4)Category revisions.

a. From time to time it may be necessary for the department to change an assigned access category because of changes in roadway conditions, traffic growth or highway reconstruction. Reassignment shall be consistent with subrule 112.5(3). A report shall be prepared presenting why the current category should not be used and the reasons for and benefits of making the category revision.

b. If the highway is identified as a future freeway or expressway, the department may suspend the issuance of new access permits.

c. If a highway utilizing at-grade intersections is intended to be improved to accommodate traffic growth or safety considerations, the access category of the future improvement shall be applied.

(5)Interchange and intersection access control.

a. When it is necessary for an at-grade access connection to be near an interchange on an access category E or ME, the first access connection location will be determined by calculating the functional areas of the expressway ramp and the first at-grade access connection. The two functional areas shall not overlap. The functional area of the ramp shall be considered no less than 1,500 feet from the end of the taper. The first access should be a public intersection. Access turning movements may be restricted for operational reasons.

b. Access is prohibited without exception to all elevated structures and ramps on or connected to any highway.

c. When the interchange crossroad AADT will exceed 10,000 in the 20th year, the first full-movement access connection should be at least 1,320 feet as measured from the ramp bifurcation point. A minimum of 1,000 feet may be allowed for a full-movement intersection if there is a proven necessity and no reasonable alternative. A restrictive median may be required between the ramps and the full-movement intersection. If the first full-movement intersection is at least 1,200 feet from the ramp bifurcation and a restrictive median is present, a right-in and right-out access may be permitted at a minimum of 600 feet from the ramp bifurcation. The ramp functional area should not overlap with the functional area of any access connection.

d. When the interchange crossroad AADT will be between 3,000 and 10,000 within 20 years, the first full movement should be at least 1,000 feet away from the ramp. All access types may have a restricted right-in and right-out access at a minimum of 600 feet from the ramp bifurcation point.

e. When the interchange crossroad AADT will not exceed 3,000 within 20 years, access public intersections and private access types A and B should be at least 600 feet away from the ramp bifurcation point. Types C and D should be at least 300 feet from the bifurcation point and may be subject to operational restrictions.

f. For any new interchange or interchange reconstruction, access rights should be acquired and extend a minimum of 600 feet away from the ramp bifurcation point. If the AADT will exceed 10,000 within 20 years, a minimum of 1,000 feet of access rights should be acquired.

g. Where a free-flow turning movement from a roadway or ramp merges onto another roadway, an analysis shall be completed to determine the functional area and the preferred placement of the first access connection. The functional area of the merge lane of the roadway and the functional area of the first access connection shall not overlap. Access rights shall be acquired along the identified functional area length.

h. An at-grade intersection shall be defined by the determination of its functional area. Access should not be allowed within this functional area. Access beyond the functional area remains subject to the requirements of the access category location standards.

i. When acquiring access rights as part of a highway project, the department may acquire access rights along intersecting public roadways to protect the operation of the intersection at the highway. Acquisition of access rights should extend a distance of 150 feet from the near edge of the highway traveled way. If the intersecting public roadway AADT is predicted to exceed 3,000 within 20 years, the department should acquire access rights for a distance of 300 feet from the near edge of the highway traveled way. The department may lengthen or shorten the distance of access rights required after considering the intersection functional area, traffic volumes, traffic operations, acquisition costs and other factors.

(6)Access management plans and agreements.

a. Access management plans may be developed to determine how access will be managed on select sections of high-priority corridors, around freeway interchanges, and within municipalities and high-growth corridors. Each plan will apply access management techniques, identify acceptable traffic control features, and establish the necessary operational restrictions to ensure the long-term functional performance and safety of the highway. The scope of each access plan may vary depending on what is determined necessary by the parties of the agreement to manage current and predicted future highway conditions and local land use.

b. To apply an access management plan within a municipality, it must be adopted by joint agreement in accordance with Iowa Code sections 306.4(4) and 306A.7.

c. Highway projects and corridor plans may include access management techniques and improvements to bring a section of highway into conformance with its current access category without adopting an access management plan and agreement.

Iowa Admin. Code r. 761-112.5

Amended by IAB October 5, 2022/Volume XLV, Number 7, effective 11/9/2022