(A) The purpose of subdivision design and application of improvement standards is to create a functional and attractive development that is consistent with the community's vision, goals, and policies found within the comprehensive plan and design goals set forth in this chapter or other land use ordinances. Design standards are intended to provide direction and ensure that subdivision improvements will be compatible with the city's public utility and transportation systems. An express grant of discretion to vary from these standards is empowered to the city council or city public works superintendent on the basis of sound engineering judgment. To promote this purpose, subdivisions shall conform to the following general guidance standards.
(B) General requirements are those that apply to all subdivisions proposed within the city's jurisdiction. In addition to the requirements established in these regulations, all subdivisions shall comply with the following:
1. All applicable statutory provisions including Chapter 13, Title 50, Idaho Code.
2. This title and adopted construction standards.
3. Any rules administered or applied by the Idaho Department of Environmental Quality, Eastern Idaho Public Health District 7, and/or appropriate state agencies.
4. The rules and regulations of the local highway jurisdiction and the Idaho Transportation Department, if the subdivision or any lot contained therein abuts a state highway; and
5. The construction and design standards and regulations adopted by the city council.
(C) All surveys for subdivisions within the limits of the city's jurisdiction shall be based upon the appropriate horizontal control network for the City of Grace. The survey shall contain or be accompanied by the information supplied by survey control agency in Caribou County.
(D) Per I.C. § 50-1307, the proposed name of a subdivision shall not duplicate, or closely approximate the name of any other subdivision in the county. Subdivision naming shall be reviewed and approved by the administrator.
(E) Street addresses shall be assigned in accordance with the addressing system in effect within the jurisdiction. Addresses will be assigned prior to issuance of any building permit on any lot.
(F) Names for new streets may be proposed by the applicant and must be approved as part of subdivision approval. Street names shall not duplicate existing street names unless the proposed street is a continuation of or is in alignment with an existing street. Street names shall be reviewed and approved by the city prior to being entered into the emergency service 911 system. Street names shall be easily pronounced, not to be confused with similar words.
(G) Streets shall be designed to comply with city standards as approved by the city council and on file with the city's public works superintendent, and the current editions of the Idaho "Standards For Public Works Construction" (prepared by the Idaho Public Works Association), and American Association of State Highway Transportation Officials (AASHTO) "Geometric Guidelines." Street signage, striping and traffic control shall be designed to comply with the latest version and exceptions of the "Manual on Uniform Traffic Control Devices" (MUTCD) as adopted per Idaho Code and city standards, as approved and on file with the city's public works superintendent. Streets or highways under the jurisdiction of other agencies shall be designed to the current standards of those agencies.
(H) Street and rights-of-way design requirements. Rules for streets and lots shall be as follows:
1. The minimum width for any street shall be fifty-two feet sixty feet (60'), except by special use permit for purely local drives.
2. All streets and other public spaces and easements shall conform in effect to the official transportation plan, both as to location and as to width or size.
3. When adjoining undeveloped property, a half street may be dedicated.
4. The minimum width of any alley, wherever provided, shall be fifteen feet. Where alleys are not provided, easements may be required along lot lines of or across lots where necessary for the extension of water mains, sewers, and similar purposes.
5. No block shall be longer than one thousand feet between street lines. Requiring a sixty foot (60') right of way.
6. The arrangement of streets in new subdivisions shall make provision for the direct continuation of the principal existing streets in adjoining subdivisions (or their proper projection where adjoining property is not subdivided) insofar as they may be necessary for public requirements. In general, such streets shall be a width at least as great as the existing streets. The street and alley arrangement must also be such as to provide opportunity for access and use by adjoining property owners. Wherever a street is stub ended so that it will not end open into another street, No cul-de-sac shall be allowed.
7. At important intersections and at all acute corners, the property corner shall be rounded or cut off.
8. All curb corners shall have radii of not less than twelve feet and at important corners not less than twenty-four feet.
9. Grades of streets shall be the lowest feasible and no grade shall be in excess of five percent on through traffic streets nor in excess of ten percent on any other street.
10. Whenever streets or alleys are paved or surfaced, such paving or surfacing shall be of a type and strength suitable for the volume and character of traffic to be expected.
11. All improvements shall conform to the best engineering standards. Due consideration shall be given throughout to the appearance of the subdivisions and the various features thereof within its own boundaries and also in its environment in the city.
12. Other rights-of-way and street sections may be adopted by the city for special circumstances to meet overall transportation needs.
(I) Rights-of-way or easements for pedestrian walkways shall be required where necessary, to provide convenient pedestrian circulation throughout subdivisions to major roadways, schools, parks, shopping areas, or other pedestrian attractions.
(J) Utility, sidewalk, and drainage easements shall be provided along all rights-of-way. The easements will vary between ten feet and twenty feet depending upon the street design and available rights-of-way.
(K) Storm drainage shall be designed to accommodate onsite the design storm event and provide for the first half-inch of runoff. The treatment methodology shall comply with the Idaho Department of Environmental Quality's best management practices.
(L) Sanitary sewer and water design shall be in conformance with the city's water and wastewater master plans and construction standards. Utility designs shall additionally conform to local standards as set forth by plans and ordinances of the city, and rules enforced by the Idaho Department of Environmental Quality, the Southeastern Idaho Public Health District 6, and other appropriate agencies.
(M) Utilities shall be installed and extended to carry service beyond the proposed development through extensions to property lines and by providing appropriate line size, depth, and location. When utility extensions are required to provide service to and along the perimeter of developments, main or service laterals to adjoining properties are to be provided per the city's direction Idaho Public Standard Works (latest edition).
(N) Dry utilities (electrical, cable, gas, etc.) shall be located within the right-of-way or easements per city standard construction details. Dry utilities shall be coordinated to minimize the use of available rights-of-way or easements and shall be installed to accommodate future roadway expansions.
(O) Residential Lot Access. Every lot shall have sufficient access to accommodate emergency vehicles. If driveway access locations are indicated within the subdivision plans, they shall comply with driveways and curb cut standards in this code.
(P) Residential Lot Frontage. All residential lots shall abut a publicly dedicated street, or an approved private street.
(Q) Commercial Subdivision Design:
1. Limited Access to Arterial and Collector Streets. Access points shall be shown on the subdivision plan and become part of the recommendation by the planning and zoning commission and the decision of the city council.
2. Commercial/Industrial Lots. Lots within a commercial/industrial subdivision are not required to front on a public street but must have access provided through an easement or other dedicated arrangement. Review and approval of commercial/industrial subdivisions should consider the types of uses envisioned and shall focus on infrastructure provisions, circulation design, potential traffic impacts and mitigation, access provisions, and any other issues identified by staff through pre-application review that pertain to the proposed subdivision.
3. Commercial Standards. The applicant shall show that the streets and block patterns proposed are suitable for the uses anticipated and compatible with other potential or existing uses in the vicinity. Residential uses adjacent to commercial subdivisions shall be protected from potential nuisances (noise, odor, light, etc.) through the use of buffers, landscaping, setbacks, or open space. (Ord. 2020-5, 9-16-2020; amd. Ord. 2022-3, 7-6-2022)