§ 107-16. Subdivision design standards.

(a)

Street alignment.

(1)

The arrangement, character, extent, width, grade, and location of all streets shall conform to the comprehensive plan, and the major streets plan, and shall be considered in their relation to existing and planned streets, to topographical conditions, to public convenience and safety, and in their appropriate relation to the proposed uses of the land to be served by the streets.

(2)

Where not shown in the comprehensive plan, the arrangement of streets in a subdivision shall either:

a.

Provide for the continuation of appropriate projection of existing principal streets in surrounding areas; or

b.

Conform to a plan for the neighborhood approved or adopted by the commission to meet a particular situation where topographical or other conditions make continuance or conformance to existing streets impracticable or of inappropriate city design.

The width of the streets in new subdivisions shall be not less than the minimum widths established herein or as otherwise determined by the commission based on traffic engineering and land use analyses. The street and/or alley arrangement shall not cause a hardship to adjacent property owners' access to adjacent public streets.

(3)

Where the parcel of land is subdivided into larger tracts than ordinarily used for building lots, the parcel shall be divided so as to allow for the opening and the ultimate extension of adjacent minor streets. Easements providing for the future opening and extension of these streets or thoroughfares, may at the direction of the council, be made a requirement of the plat.

(4)

Minor streets shall be so laid out that their use by through traffic will be discouraged.

(5)

Where a subdivision abuts or contains a major street the commission may require a parallel access street or where the back end of the lot faces the major street and the lot has double frontage with access only on the adjacent minor street, or any other treatment as may be necessary for adequate protection of residential properties and to afford separation of through and local traffic.

(6)

Where a subdivision borders on or contains a railroad right-of-way or limited access highway right-of-way, the commission may require a street approximately parallel to and on each side of the right-of-way, at a distance suitable for the appropriate use of the intervening land, as for park purposes in residential districts, or for commercial or industrial purposes in appropriate districts. These distances shall be determined with due regard for the requirements of approach grades and future grade separations.

(7)

Reserve strips controlling access to streets shall be prohibited except where their control is definitely placed with the city under conditions approved by the commission.

(8)

Streets with centerline offsets of less than 150 feet shall be avoided.

(9)

A tangent of at least 100 feet long shall be introduced between curves on arterial and collector streets.

(10)

When connecting street lines deflect from each other at any one point by more than ten degrees, they shall be connected by a curve with a radius adequate to ensure a slight distance of not less than 100 feet for minor and collector streets, and of a greater radii as the commission shall determine for special cases.

(11)

Streets shall be laid out so as to intersect as nearly as possible at right angles and no street shall intersect any other street at less than 50 degrees.

(12)

Property lines at street intersections shall be platted with a radius or an acceptable chord length, as the commission may deem necessary.

(13)

Half streets shall be prohibited, except where essential to the reasonable development of the subdivision in conformity with the other requirements of this chapter; and where the commission finds it will be practicable to require the dedication of the other half where the adjoining property is subdivided. Wherever a half street is adjacent to a tract to be subdivided, the other half of the street shall be platted within the tract.

(14)

Dead-end streets, designed to be so permanently, shall provide a closed end with a cul-de-sac having a minimum outside roadway diameter of at least 60 feet and a street property line diameter of at least 80 feet.

(15)

No street names shall be used which will duplicate or be confused with the names of existing streets. Street names shall be subject to the approval of the commission.

(b)

Street grades. Street grades, wherever feasible, shall not exceed the following, with due allowance for reasonable vertical curves:

Street Type	Percent Grade
Arterial or major	5
Minor	10

 

(c)

Street right-of-way.

(1)

Street right-of-way widths for major streets will be shown on the major streets plan of the comprehensive plan as 80 feet.

(2)

Street right-of-way widths for minor streets shall be 60 feet for streets designed for on-street parking and a minimal 30 feet shall be dedicated whenever subdivided property adjoins a half street as designated by the commission. The remainder of the street shall be dedicated. No homes shall be constructed on half streets.

(d)

Alleys or service drives and yards. Alleys may not be provided in a residential block. Alleys are required in the rear of all business lots unless other adequate provisions are made for service and deliveries, and shall be at least 20 feet wide.

(e)

Blocks. No block shall be longer than 1,200 feet. Where blocks are over 600 feet in length, a pedestrian way with a right-of-way of at least 16 feet in width may be required near the center of the block.

(f)

Lots.

(1)

The lot arrangement and design shall be so that all lots will provide satisfactory and desirable building sites, properly related to topography and to the character of surrounding development.

(2)

No residential lot shall be less than 80 feet in width at the building line, or less than 8,800 square feet.

(3)

Corner lots shall have extra width sufficient to permit the establishment of front building lines on both adjoining streets.

(4)

In all lots so far as possible, the side lines shall be at right angles to straight street lines or radial to curved street lines, except where a variation of this rule will provide a better street and lot layout.

(5)

Double frontage and reverse frontage lots shall be avoided, except where their use will produce definite advantages in meeting special situations in relation to topography, sound site planning and proper land use.

(g)

Public sites and open spaces. Where an area being subdivided includes lands, proposed to be used for parks or schools under the comprehensive plan of the city, the subdivider shall indicate the location of the areas on the subdivision plat. The subdivider shall dedicate land for the areas equivalent to ten percent of the gross area. Park area in excess of that dedicated and lying within the city limits is to be purchased within two years of the recording date of the subdivision by the city at the appraised raw land value prior to subdivision, plus one-half of the cost of grading and paving, including curbs, of the portion of any streets that are contiguous to the site. Park sites outside the city limits are to be reserved for three years, giving any authorized public agency the option to purchase the land at the appraised raw land value prior to subdivision, plus one-half of the cost of grading and paving, including curbs, of the portion of any streets that are contiguous to the site. School sites are to be reserved for four years, giving the school district the right to purchase the land at the appraised raw land value prior to subdivision, plus one-half the cost of grading and paving, including curbs, of any streets contiguous to the site. Should the park or school sites not be purchased within the time limit specified above, the subdivider may then sell them for an alternate purpose as shown on the approved subdivision plan.

(h)

Character of development. The commission and city council may require that certain minimum regulation regarding type and character of development be incorporated in the owner's declaration of plat. These regulations shall be intended to protect the character and development of the platted subdivision as well as that of the surrounding development.

(i)

Streams and watercourses. Wherever any stream or surface watercourse is located in an area that is being subdivided, the subdivider shall, at the subdivider's expense, make adequate provisions for the proper drainage of surface water and shall also provide and dedicate to the city land along the streams and watercourses, meeting the approval of the commission. Open space to be preserved for utility and public facility usage along natural drainage courses as shown in the comprehensive plan, or the officially adopted stormwater drainage plan or parks, schools, and playgrounds plan, if any, shall be dedicated to the city in amount equal to ten percent of the value of the platted land with any additional required land reserved in the plat for purchase by the city by benefit assessment including the platted lots or by a direct purchase method.

(j)

Maintenance of improvements outside corporate limits. Where a subdivision outside the corporate limits contains sewers, sewage treatment plants, water supply systems, park areas, street trees, or other physical facilities necessary or desirable for the welfare of the area and which are of common use or benefit and which the city does not desire to or cannot maintain, provision shall be made by trust agreements, made a part of the deed restrictions, acceptable to the city for the proper and continuous maintenance and supervision of the facilities by the lot owners in the subdivision.

(k)

Easements for public utilities. Public rights-of-way dedicated for alleys, parks, and service roads may be used for public utilities. All easements to be granted for utilities shall be constructed as either pedestrian walkways, park-ways, plazas, open spaces or playgrounds as may be deemed appropriate by the commission. All easements and rights-of-way for parks or service roads or alleys shall not be less than 16 feet totally or eight feet granted by each adjoining owner. Larger dimensions may be required where it is necessary for extension of main sewers or other utilities or where both water and sewer are located in the same easement. No buildings or structures will be permitted on any part of an easement.

(Prior Code, § 122.16)