1. Acreage Subdivisions. Where the parcel of land is subdivided into larger tracts than ordinarily used for building lots, such parcel shall be divided so as to allow for the opening of major streets and the ultimate extension of adjacent minor streets. Easements providing for the future opening and extension of such streets, may, at the discretion of the Council, be made a requirement of the plat.
2. Relation to Adjoining Street System. New subdivisions shall make provisions for the continuation of the principal existing streets in adjoining additions (or for their proper projection where adjoining property is not subdivided) insofar as they may be necessary for public requirements. In general, such street shall be of a width as great as that of the streets so continued or projected but shall not be less than the minimum width requirement.
3. Street Arrangements. The street system shall be so arranged to comply as far as practicable, with the Major Street Plan of the City. Streets shall intersect as nearly as possible to a right angle and in no case shall they intersect at less than 60 degrees. No street shall be parallel or approximately parallel to a railroad, unless it is 150 feet or more from the line of the railroad right-of-way. Street jogs with centerline offsets of less than 125 feet shall be avoided.
4. Street Width.
A. The widths for all street rights-of-way shall conform to the specific street types as designated on the Major Street Plan in the Comprehensive Development Plan.
B. The minimum width for streets shall be 62 feet between property lines, except that in cases where the topography or special conditions make a street of less width more suitable, the Commission and the Council may waive the above requirement.
C. Half streets shall be prohibited, except where essential to the reasonable development of the subdivision in conformity with the other requirements of these regulations; and where the Commission finds it will be practicable to require the dedication of the other half when 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 such tract.
5. Street Grades. Street grades, if practical, shall not exceed six percent for all arterial and collector streets and ten percent for all minor streets and no grade shall be less than one-half of one percent.
6. Alleys. The minimum width of an alley in a residential block shall be 16 feet (alleys are not recommended for residential districts except under unusual conditions). Alleys will be required in the rear of all business lots and shall be at least 24 feet wide. Dead-end alleys shall be avoided where possible, but if unavoidable, shall be provided with adequate turnaround facilities at the dead end.
7. Easements Where There Are No Alleys. Where alleys are not provided, easements of not less than 5 feet in width shall be provided on both side lot lines and an easement of not less than 10 feet in width shall be provided on all rear lot lines where necessary for poles, wires, conduits, storm and sanitary sewers, gas, water, and heat mains. Easements of greater width may be required along lines or across lots where necessary for the extension of main sewers and similar utilities. The subdivider shall consult with the City Engineer, the Superintendent of Utilities, and the Manager of the local telephone company as for the need and location of easements.
8. Places. Where it is desired to subdivide a parcel of land, which, because of its size or location, does not permit a normal lot or street area, there may be established a “Place.” Such a place may be in the form of a court, non-connecting street, or other arrangement, provided, however, that proper access shall be given to all lots from a dedicated place (street or court). If any dead-end place (street or court) is more than 250 feet in length, it shall terminate in an open space, preferably circular, having a minimum diameter of 110 feet. Except in unusual instances, no dead-end street or place shall exceed 600 feet in length.
9. Blocks. All blocks shall be required to have a minimum length of 300 feet and a minimum depth of 200 feet.
10. Lot Lines. All side lines of lots shall be at right angles to straight street lines, or radial to curved street lines, unless a variation to this rule will give a better street and lot plan. Double frontage, and reverse frontage lots shall be avoided except where essential to provide specific disadvantages of topography and orientation. A planting screen easement of at least 10 feet shall be provided along the line of lots abutting such a traffic artery or other disadvantageous use and no right of access shall be provided across said easement.
11. Size and Shape of Lots. Minimum lot size shall be governed by the City zoning regulations except that, where on-site sewage disposal and/or water supply are proposed, the following lot sizes shall be required:
A. Where both water supply and sanitary sewage disposal are provided by individual on-lot facilities, lots for single-family detached dwellings shall have a minimum area of 20,000 square feet and a minimum width at the building line of 100 feet.
B. Where only water supply or sanitary sewage disposal facilities are to be provided on the lot, lots for single-family detached dwellings shall have a minimum area of 10,000 square feet and a minimum width at the building line of 70 feet.
C. In either of the above cases, the Commission may require that the subdivider have such tests made by the City Health Officer as will determine the adequacy of the proposed facilities in relation to the proposed lot size and existing topographical and soil conditions. When such tests are required, a certificate of adequacy of the proposed facilities made by the City Health Officer shall be prerequisite to final approval of the plans. Lots shall be conveniently shaped, and the depth of lots shall generally not exceed their width by more than 2½ times, provided the width is at least 60 feet at the building line. Each lot shall have at least 20 feet of frontage on a street.
12. Street Names. Streets that are obviously in alignment with others already existing and named shall bear the name of existing streets; otherwise, names shall not duplicate existing street names, and names similar to existing street names shall not be permitted.
13. Building Lines. Building lines shall be shown on the plat or included in the owner’s statement on all lots whenever the depth of such building lines is greater than those required by the zoning regulations. Provisions shall be made in the owner’s statement requiring all enclosed parts of buildings to be set back to such building lines.
14. Character of Development. The Commission and the Council may require that certain minimum regulations regarding type and character of development be incorporated in the owner’s statement of plat. Such regulations shall be intended to protect the character and development of the platted subdivision, as well as that of the surrounding development.
15. Easements Along Streams and Water Courses. Whenever any stream or surface watercourse is located in an area that is being subdivided, the subdivider shall, at the subdivider’s own expense, make adequate provisions for the proper drainage of surface water and shall also provide and dedicate to the City an easement along said streams and watercourses meeting the approval of the Council.
16. Improvements. Before the final plat of any subdivision shall be approved by the Commission or the Council, the developer shall make and install all of the improvements required by this subsection, unless the Council permits the developer to enter into a contract for the making and installation of said improvements after the approval of the final plat. If the Council permits the developer to enter into a contract for the making and installation of improvements after the approval of the final plat, it may require that the developer file a bond in such amount as it finds necessary to secure the making and installation of such improvements. Construction plans and specifications shall be filed with the Commission and approved by the Commission and the Council before the making or installation of any improvements.
A. Street Grading and Surfacing. All streets within any subdivision shall be brought to grade established from the City datum plane. All street surfaces shall conform in width as designated on the Major Street Plan in the Comprehensive Development Plan.
(1) Two eight-foot parking lines may be provided for collector and minor streets in areas where they are warranted by need; however, no on-street parking shall be allowed on State, regional and arterial roads except within the area of the Central Business District, in which case sufficient additional street surface width must be provided for such parking. All streets shall have integral concrete curb and gutter according to the City Engineer’s specifications.
(2) All subdivision streets shall be paved with Portland Cement Concrete at least 7 inches in thickness or with asphaltic concrete having equivalent strength and wearing qualities.
B. Water Service. Where a public water main is reasonably accessible, the developer shall connect with such water main and provide a water connection for each lot with service pipe installed to the property line in accordance with the City Water Department standards, procedure and supervision.
C. Storm Sewers. The developer will be required to construct adequate storm sewers in each subdivision.
D. Sanitary Sewers. Within the subdivision the developer will be required to construct sanitary sewers in accordance with the State Board of Health regulations, and plans for said sewers shall be approved by the State Board of Health before construction, and approved plans shall be filed with the City Clerk prior to construction.
E. Engineering. The City shall not be responsible for engineering costs associated with the new subdivision. All the above-mentioned facilities constructed under the provisions of this chapter shall be inspected and shall be subject to the approval of the City Engineer or a representative of the City acting in the capacity of City Engineer and the developer shall reimburse the City for all costs of inspection. All material used shall be required to meet all the following standards: American Association of State Highway Officials, American Society for Testing Materials, American Waterworks Association and Iowa State Highway Commission specifications.
F. Off-Street Parking. Each lot shall have off-street parking provisions as provided in the zoning regulations.
G. Sidewalks. The developer shall provide sidewalks of Portland Cement concrete 4 feet in width and 4 inches in thickness. Sidewalks shall be 6 inches thick through driveways.
H. Street Markers. The developer shall provide street markers at intersections as approved by the City.
I. Other Improvements. The Council may also require other improvements and any other accessories normally found in a residential area.
17. Soil Erosion and Sediment Control Plan. Construction plans and specifications filed pursuant to subsection 16 of this section shall include a Soil Erosion and Sedimentation Control Plan approved by the City Engineer with adequate provisions for erosion and sediment control measures. No plans and specifications for improvements in a subdivision shall be approved unless the Commission and the Council find that the plans and specifications include erosion and sediment control measures necessary to comply with the soil loss limit regulations adopted by the Crawford County Soil Conservation District on August 30, 1972. No clearing, grading, or construction work shall be done in any subdivision until the issuance of a Land Disturbance Permit and erosion and sediment control measures in accordance with the Soil Erosion and Sedimentation Control Plan have been provided in compliance with approved plans and specifications.
(Ord. 1372 – Jan. 10 Supp.)