Article 10. Project Design Standards. Table of Contents. page

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1 Article 10. Project Design Standards Table of Contents page Sec Purpose of Article Sec Standards incorporated by reference (a) Standard Design Specifications (b) Traffic signs and street striping (c) South Carolina DOT standard specifications (d) AASHTO design standards Sec Interpretation of standards (a) Governing Standards (b) Prior Acceptance of Construction Plans Sec Design exceptions and field changes (a) Request for Design Exception (b) Field changes Sec General design standards (a) Suitability of the land (b) Conservation (c) Conformance to the comprehensive plan and other adopted plans (d) Name of subdivision or development project (e) Street names (f) Street Addresses (g) Blocks (h) Lots (i) Areas reserved for future development (j) Plats & Developments Straddling Political Boundaries Sec Required improvements (a) Minor subdivisions (b) Major subdivisions, multi-family and nonresidential developments Sec Guarantee in lieu of completed improvements. (2/16/10) (a) Performance Surety (b) Performance Surety Default Table Sec Survey Monuments (a) Exterior development boundaries (b) Lot and street corners (c) Floodplain Elevations Sec Easements (a) Utility easements Pickens County UDSO: Amended 2/16/10 10-i

2 Article 10 Project Design Standards 1009 (b) Pedestrian Easements (c) Drainage and access easements (d) Conservations easements (e) Overlapping easements Sec Streets (a) Access (b) Street classifications (c) Relation to present and future street system (d) Design standards for streets Table 10.2: Minimum Right-of-Way Width Table 10.3: Street Grades and Design Speed Figure 10.1 Horizontal Curves Figure 10.2 Reverse Curves Table 10.4 Intersection Offset Figure 10.3 Intersection Offsets Figure 10.4 Mitered Right-of-Way Table 10.5: Minimum Sight Distance Figure 10.5 Sight Distance Figure 10.6 Interim Turn-Arounds Figure 10.7 Cul-de-sac Dimensions Figure 10.8 Subsurface Drainage Figure 10.9 Entry Island Layout Figure Island Detail Figure Intersection/Driveway Grades (e) Street Improvements Table 10.6: Street Base and Pavement Figure Guardrail Cross Section (f) Substandard streets Sec Minimum maintenance roads (a) Criteria (b) Determination (c) Restrictions (d) Procedure for acceptance Sec Private residential access (a) Shared driveways (b) Common drive (c) Private Roads Sec Street signs, traffic signs and striping (a) Street name signs (b) Traffic Signs (c) Striping Requirements Sec Street Lights Sec Driveway and Development entrances (a) Driveway access to a State road (b) Driveway access to major County roads ii Pickens County UDSO: Amended 2/16/10

3 Article 10. Project Design Standards 1015 (c) Driveway standards; in general (d) Residential subdivision entrances (e) Commercial/Industrial subdivision entrances (f) Driveways for multi-family and non-residential developments (g) Maintenance of sight distances Sec Deceleration lanes and turn lanes (a) Deceleration lanes; where required (b) Median breaks (c) Deceleration and turn lane constructions standards Sec Sidewalks (a) Sidewalks; where required (b) Sidewalks; where located (c) Sidewalks; construction Sec Location of utilities and street cuts (a) Location of utilities in streets Sec Storm drainage (a) Applicability and exemptions (b) Standards to be used in designing system: Sec Public water system Sec Public sewerage system Pickens County UDSO: Amended 2/16/10 10-iii

4 Article 10 Project Design Standards BLANK PAGE 10-iv Pickens County UDSO: Amended 2/16/10

5 Sec Purpose of Article 10. Article 10. Project Design Standards Sec Purpose of Article 10. This Article sets out the minimum requirements and standards for construction of subdivisions and other land development projects, including general principles of design and layout and requirements for such public facilities as streets and utilities. Low impact development procedures may be used where practical. Grass swales, pervious pavements and other best management procedures may be used where storm water velocities and quantities allow. Each low impact practice will be approved on a case-by-case basis. Sec Standards incorporated by reference (a) Standard Design Specifications. The Standard Design Specifications of Pickens County, also referred to in this Ordinance as Standard Details, as adopted by the County Council and as may be amended from time to time are incorporated into this Ordinance as though set forth within the body of this Ordinance. In the case of a conflict between the Standard Design Specifications and the text of this Ordinance, the text shall control (b) Traffic signs and street striping. The installation of all traffic control signs and street striping shall be governed by the standards contained in the Manual on Uniform Traffic Control Devices, latest edition, published by the Federal Highway Administration of the U.S. Department of Transportation (c) South Carolina DOT standard specifications. Unless otherwise specially set forth in this Ordinance or the Standard Design Specifications of Pickens County, all of the materials, methods of construction, and workmanship for the work covered in reference to street construction and storm drainage construction shall conform to the latest standard specifications of the South Carolina Department of Transportation (d) AASHTO design standards. Design criteria and standards not specifically set forth herein shall conform to the latest edition of the AASHTO Policy on Geometric Design of Highways and Streets. Sec Interpretation of standards. In the interpretation and application of the provisions of these standards, the following shall govern: 1003 (a) Governing Standards Whenever a provision of these standards or any provision in any law, ordinance, resolution, rule, or regulation of any kind contains any restrictions covering any of the same subject matter, the standards that are more restrictive or impose higher standards or requirements shall govern (b) Prior Acceptance of Construction Plans Pickens County shall not modify or alter any development plans that have been filed with and accepted by the County prior to the effective date of this code. This excep- Pickens County UDSO: Amended 2/16/

6 Sec Design exceptions and field changes. tion shall be subject to the conditions and limitations under which said plans were accepted by the County. Sec Design exceptions and field changes (a) Request for Design Exception When unique conditions and circumstances exist on a project, the developer s engineer may submit a request for design exception in a format provided by the County Engineer. Design exceptions request should be identified as early as possible during the design process. The County Engineer is the approval authority for design exceptions. Any design exception request not considered by the County Engineer, or otherwise not approved, may be forwarded to the Planning Commission for their review and consideration (b) Field changes Minor changes in construction plans caused by field conditions shall be made at the direction of the County Engineer with the cost of such changes to be paid by the developer. All changes are to be documented as revisions to the approved development plans and correctly shown on the as-built surveys. Discrepancies between the as-built surveys and the approved development plans may result in delays in approving final plats or certificates of occupancy. Sec General design standards (a) Suitability of the land. (1) Land physically unsuitable for subdivision or development because of flooding, poor drainage, topographic, geologic or other such features that may endanger health, life or property, aggravate erosion, increase flood hazard, or necessitate excessive expenditures of public funds for supply and maintenance of services shall not be approved for subdivision or development unless adequate methods are formulated by the developer for solving the problems. Such land shall be set aside for such uses as shall not involve such a danger. (2) Land within a proposed subdivision or development which is unsuitable for development shall be incorporated into the buildable lots as excess land or may be utilized as openspace. Lots that do not comply with the requirements of this Ordinance are prohibited (b) Conservation. (1) Development shall be planned, designed, constructed and maintained to avoid substantial probabilities of: a. Accelerated erosion. b. Pollution, contamination, or siltation of lakes, rivers streams, and other water bodies. c. Damage to vegetation. d. Injury to wildlife and fish habitats. (2) Development shall be planned, designed, constructed and maintained to provide open space and to create a man-made environment for human use or occupancy compatible and harmonious with the natural environment and specific consideration shall be given to the preservation of natural topography, to preservation of existing vegetation, to retention of major land forms and to preservation of important vistas Pickens County UDSO: Amended 2/16/10

7 Sec General design standards (c) Conformance to the comprehensive plan and other adopted plans. In addition to the requirements established herein, all subdivisions and individual development projects shall comply with the following laws, rules and regulations: (1) All proposed subdivisions and individual development projects shall conform to the Comprehensive Plan and development policies in effect at the time of submission to the Community Development Department. (2) All highways, major thoroughfares, streets and other transportation facilities shall be platted by the developer in the location and to the dimension indicated on the Comprehensive Plan or the County Transportation Plan, if applicable, whichever is the most recently adopted or amended. (3) When features of other plans adopted by the County Council (such as school sites or other public-building sites, parks or other land for public uses) are located in whole or in part in a subdivision, such features shall be either dedicated or reserved by the subdivider for acquisition within a reasonable time by the appropriate public agency. a. Whenever a plat or site plan proposes the dedication of land to public use that the County Council finds to be not required or suitable for such public use, the County Council shall refuse to accept the dedication. (4) In subdivisions or developments related to or affecting any State or U.S. numbered highway, the Community Development Department shall require the approval of the South Carolina Department of Transportation. (5) Any and all rules of the South Carolina Department of Health and Environmental Control (DHEC), the USDA Natural Resource Conservation Service, and all other appropriate state and federal agencies (d) Name of subdivision or development project. The name of each subdivision or development project must have the approval of the Community Development Department. The name shall not duplicate nor closely approximate the name of an existing subdivision or development project in Pickens County or any of its cities (e) Street names. (1) Street names. a. Proposed streets obviously in alignment with other existing and named streets shall bear the names of the existing streets. In no case shall the name for a proposed street duplicate existing street names in Pickens County. b. Street names are subject to approval by the E911 Addressing Coordinator (f) Street Addresses Street addresses shall be obtained from the E911 Addressing Coordinator and shall be shown upon each final plat. Numbers must be visible from the street. The size of the address numbers must be a minimum of 3 inches tall (g) Blocks. (1) Residential Blocks. a. Unless otherwise approved by the County Engineer under unusual circumstances, block lengths shall not exceed 1,200 feet nor be less than 400 feet in length. Pickens County UDSO: Amended 2/16/

8 Sec General design standards. b. In blocks greater than 1,200 feet in length, the County Engineer may require one or more public easements of not less than 20 feet in width to extend entirely across the block for pedestrian crosswalks, fire protection or utilities. c. Width: Blocks shall be wide enough to allow two rows of lots, except where reverse frontage lots on major thoroughfares are provided, or when prevented by topographic conditions or size of the property, or for lots along the periphery of the subdivision, or where abutting upon limited access highways or railroads, or where other situations make this requirement impractical, in which case the Community Development Director and County Engineer may approve a single row of lots. (2) Nonresidential Blocks. Blocks for other than residential use shall be of such length and width as may be suitable for the prospective use, including adequate provision for off-street parking and service (h) Lots. (1) Minimum lot dimensions and areas. All lots shall meet or exceed the area and dimensional requirements of this Development Ordinance. (2) Authority of DHEC. Nothing contained in this Article shall be construed as preventing the DHEC, after study of the conditions existing in a proposed subdivision, from requiring that all or any portion of the area of such subdivision shall not be built upon or that the minimum lot sizes set forth in this Development Ordinance are inadequate and must be increased to ensure the protection of the public health. (3) Adequate building sites. Each lot shall contain a site large enough for a normal building that will meet all building setback requirements as set forth in this Ordinance and not be subject to flood or periodic inundation (4) Arrangement. If possible, all lot lines that intersect a street line shall be perpendicular or radial to said street lines unless not practical or desirable because of topographic or other features, such as the location of a stream or other natural feature that more appropriately may define a lot, or a property line that forms the periphery of a subdivision that is not perpendicular or radial to a street line. Exceptions to this requirement must be approved by the Director of Community Development at the time of Preliminary Plat approval or otherwise prior to recordation of the lot. In no case shall a lot be created that would require a variance to provide an adequate area to accommodate a normal principal building Pickens County UDSO: Amended 2/16/10

9 Sec Required improvements. (5) Corner Lots. Corner lots shall be sufficiently large to permit the location of buildings so as to conform to the front building lines on both streets. (6) Through lots. Except where specifically required to provide reverse frontage separation from a County road or a State or U.S. numbered highway, or to overcome specific disadvantages of topography and orientation of property, through lots (i.e., doublefrontage lots) are to be avoided (i) Areas reserved for future development If any portion of a tract is reserved for future subdivision development, the minimum lot width and frontage of the reserved area may be reduced to the width required for a future street to serve such area. (1) Such a reserved area must be labeled Reserved for Future Development on the final subdivision plat, and the portion of the lot where a street will be built must be labeled Future Street. (2) Such a reserved area will not be eligible for issuance of a building permit unless the lot meets all requirements of this Development Ordinance, including minimum lot width and frontage requirements (j) Plats & Developments Straddling Political Boundaries. Whenever access and/or services to a subdivision is required across land in another governmental jurisdiction, the Community Development Director may request assurance from the County Attorney, and/or the other county, and/or other municipality that access is legally established, and that the access road is adequately improved. In general, lot lines shall be laid out so as to not cross jurisdictional boundary lines. Any necessary intergovernmental agreements must be executed prior to the issuance of a Development Permit. The developer and/or property owner has an affirmative duty at the time of application for land use approval or development permit (if land use approval has already granted or not required) application to request with the affected governments that they enter into an intergovernmental agreement process. The County makes no guarantee to enter into any intergovernmental agreement. Sec Required improvements (a) Minor subdivisions. By definition, a minor subdivision does not involve the construction of major public improvements, such as new streets or stormwater detention. However, the following improvements are required in order to adequately serve the lots and protect the safe operation of the existing road: (1) Right-of-way shall be delineated along the property s frontage from the centerline of the existing road equal to ½ of the minimum requirement for the classification of the road, as established in this Article or otherwise specified by SCDOT. (2) The potential location of a driveway connection serving each lot and meeting the requirements of these development regulations shall be indicated on the final subdivision plat. (3) The stormwater carrying capacity of the road, whether in an existing ditch or gutter, shall not be compromised. If the stormwater characteristics of the existing road are inadequate to accommodate the new lots, the County Engineer may require improvement of the roadway ditch as appropriate. Pickens County UDSO: Amended 2/16/

10 Sec Guarantee in lieu of completed improvements. (2/16/10) (4) All lot corners shall be marked according to the Minimum Standards Manual for the Practice of Land Surveying in South Carolina (b) Major subdivisions, multi-family and nonresidential developments. The following improvements shall be provided by the developer or at the developer s expense in every major subdivision or individual multi-family or nonresidential development in accordance with the requirements and standards contained in this Article. (1) Survey monumentation in accordance with Sec (2) Streets providing access to such a development and to all lots in such a subdivision, including the extension of streets required to provide access to adjoining properties, in accordance with Sec a. Streets contained wholly within such a subdivision shall be improved to the full standards contained in this Article. b. Curb and gutter as required by Sec. 1010(e)(4). (3) Street name signs, stop bars, striping and traffic control signs as approved by the County shall be paid for by the developer and installed by the Pickens County Roads and Bridges Department in accordance with Sec (4) Driveway access to each lot, and project access improvements (deceleration, turn lanes, etc.) as deemed necessary by the County Engineer under the provisions of Sec and Sec (5) Sidewalks, if required under Sec (6) Storm water drainage and detention facilities in accordance with Sec (7) Public or private water supply as required under 0. (8) Public or private sanitary waste disposal as required under Sec Sec Guarantee in lieu of completed improvements. (2/16/10) 1007 (a) Performance Surety No final subdivision plat shall be approved by the County or accepted for recordation by the Register of Deeds, nor shall any lot within the development be sold or transferred until one of the following conditions has been met: (1) All public improvements shall have been properly installed and completed in accordance with all requirements and standards of this Development Ordinance and an as-built survey of the improvements shall have been approved by the County Engineer; or, (2) Pickens County has received a performance surety in the form of a letter of credit or surety bond issued by a financial institution with a presence in South Carolina or otherwise licensed to provide such services in South Carolina in the amount of 125% of the estimated cost of installation of the required improvements. (3) For residential developments, the improvements funded through the performance surety shall be limited to final pavement topping for streets, storm drainage infrastructure, curbing, grassing of street shoulders, landscaping, and street striping. For commercial or industrial developments with public infrastructure, it must cover the base, asphalt, grading, storm drainage. (4) The developer shall submit actual cost estimates prepared by the developer s engineer, contractor, or subcontractors to the Planning Department. Planning staff, along with the County Engineer, will perform a cost analysis for such infrastruc Pickens County UDSO: Amended 2/16/10

11 Sec Guarantee in lieu of completed improvements. (2/16/10) ture covered under any proposed surety. If such analysis generates a higher estimate than the estimates submitted by the developer, the higher of the two estimates will be used to determine the bond amount. (5) Completion of the improvements covered under the performance surety shall be accomplished within 12 months of the approval of the final subdivision plat. (6) Upon completion of any deferred improvements: a. The as-built plans are to be updated by the developer and submitted to the County Engineer; b. A letter from the County Engineer authorizing the release of the surety shall be provided; c. A maintenance surety required under Sec. 1102(e) shall commence for the completed deferred improvements (b) Performance Surety Default If at any point in the schedule shown in Table 10.1, below, the County Engineer determines that the installation of infrastructure is not progressing as outlined in the schedule or that the developer is not working in good faith to bring the infrastructure to County standards, the County may declare the developer in default and can proceed to secure the proceeds of the surety in order to complete the installation of the infrastructure. Table 10.1 Using Asphalt Binder Course (as approved by the County Engineer) Road base installed prior to the sale of any lots. Binder asphalt must be in place prior to the issuance of permits or the commencement of any construction. Final surface must be in place at 85% build out as determined by the County Engineer. Any and all deterioration to the road must be repaired to the satisfaction of the County Engineer within 30 days of notification by the County Engineer or within a time frame determined by the County Engineer if seasonal or weather conditions make the 30 day time frame impractical. Not Using Binder Course Road base installed prior to the sale of any lots. Surface coarse must be in place prior to the issuance of permits or the commencement of any construction. Any and all deterioration to the road must be repaired to the satisfaction of the County Engineer within 30 days of notification by the County Engineer or within a time frame determined by the County Engineer if seasonal or weather conditions make the 30 day time frame impractical. Pickens County UDSO: Amended 2/16/

12 Sec Survey Monuments Sec Survey Monuments 1008 (a) Exterior development boundaries. (1) An iron pipe or ½ inch iron pin at least 24 inches long shall be placed at all corners of the exterior boundaries of the subdivision or development project being developed. (2/16/10) (2) Existing permanent monuments that, in the professional opinion of a registered land surveyor, are of sufficiently durable construction shall be marked and maintained. (3) Other, more suitable permanent materials may be used as noted in the Standards of Practice Manual for Surveying in South Carolina, if such material provides for a permanent reference. (2/16/10) 1008 (b) Lot and street corners. (1) All other street or lot corners shall be marked with an iron pipe or ½ inch iron pin at least 24 inches long. (2/16/10) (2) All such monuments shall be properly set in the ground and shall be approved by a registered land surveyor prior to the time of final plat approval. (3) Other, more suitable permanent materials may be used as noted in the Standards of Practice Manual for Surveying in South Carolina, if such material provides for a permanent reference. (2/16/10) 1008 (c) Floodplain Elevations On developments containing floodplains, flood elevation references shall be set and noted on all plans and associated plats. Sec Easements. Easements shall be required in connection with subdivisions or developments for the following purposes, among others: 1009 (a) Utility easements. (1) Utility easements for private utilities shall be avoided except in cases where no other satisfactory arrangements can be provided for the installation of private utilities. (2) Whenever it is necessary or desirable to locate a public utility line outside of the street right-of-way, the line shall be located in an easement dedicated to the County (or other appropriate public entity) for such purpose. Easements for water and sanitary sewers shall be a minimum of 20 feet wide, and may be required to be wider depending on the depth of cut to maintain a 1:1 open cut slope. When warranted, temporary construction easements widths shall be as required by the county. (3) Easements for sanitary sewers may be required by the County Engineer or public sewage provider for future extension of lines, whether or not the subdivision or development is currently proposed to be served by public sewer (b) Pedestrian Easements Pedestrian easements not less than 10 feet wide, may be required where deemed essential to provide circulation, or access to schools, playgrounds, shopping centers, transportation, and other community facilities Pickens County UDSO: Amended 2/16/10

13 Sec Streets (c) Drainage and access easements. (1) Drainage easements shall be cleared and opened for a closed stormwater or drainage system of adequate width and capacity at the time of development to control surface water run-off. Run-off slopes and side slopes shall be specified by the developer s engineer according to good engineering practices. (2) A publicly dedicated drainage easement is to be provided along any manmade drainage channel or drainage pipe located outside a street right-of-way. All easements shall be no less than 20 feet wide when used as an open ditch. Piped storm drainage shall have a minimum easement width of 20 feet wide. (3) Drainage easements off the street right-of-way shall be clearly defined on the plat and deed of the individual property owner, and such property owner shall keep the easement free of obstructions and maintain that part of the easement within the property owner s boundary line so that free and maximum flow is maintained at all times. The property owner shall not alter any drainage improvements without the prior written approval from the county (d) Conservations easements. Conservation easements, as may be required by this Development Ordinance shall be clearly defined on the plat and deed of the individual property owner, and must conform to the requirements set out for such easements 1009 (e) Overlapping easements. Easements for water, sanitary sewers and drainage purposes may be combined, but must be a minimum of 30 feet if in combination. Any easement containing more than one pipe must provide at least 10 feet beyond the pipe and the pipes must be at least 10 feet apart (measured on center). Wider easements shall be required when necessary to maintain a 1:1 open cut slope to each pipe. Sec Streets (a) Access. (1) A publicly approved street meeting the requirements of this Article shall serve every development and every lot within a subdivision. Private streets, when constructed and approved according to Section 1011, are permitted. (2) Every development and every major subdivision shall have access to the public street system via a standard County road or an approved private street. A building permit shall not be issued unless continuous road access between the property and the public street system is provided by a publicly dedicated street or an approved private street. (3) A building permit shall not be issued on any property that does not front on or have approved access to a publicly dedicated street or an approved private street, in accordance with the minimum lot frontage and access easement provisions of this Development Ordinance. (4) When land is subdivided into larger parcels than ordinary building lots, such parcels shall be arranged and designed so as to allow for the opening of future streets and to provide access to those areas not presently served by streets. (5) No subdivision or development shall be designed in a way that would completely eliminate street access to adjoining parcels of land. (6) Reserve strips which control access to streets, alleys and public grounds shall be prohibited unless their control is placed in the hands of the County under owner- Pickens County UDSO: Amended 2/16/

14 Sec Streets. ship, dedication, or easement conditions approved by the County Attorney and the County Engineer. (7) Subdivision streets that intersect a State or U.S. numbered highway, a County arterial or County collector road shall do so at intervals of not less than 500 feet, or as required by the South Carolina Department of Transportation, whichever is greater. On all other roads, at least 250 feet must separate street intersections on the same side of the road, measured centerline to centerline. Compliance with sight distance requirements of this Development Ordinance may require greater distances between street intersections (b) Street classifications. Streets are classified according to the function that they serve, the type, speed, and volume of traffic they will carry and the required standards of design. The classifications of streets and roads are as follows: (1) Principal Arterials. These roads, which include interstates and rural freeways: serve "substantial" statewide or interstate trips, as defined by high mileage or volume; connect most urban areas of 25,000 or more and virtually all urban areas of 50,000 or more; and provide an integrated network without stub connections except where geography dictates otherwise. (2) Minor Arterials. With the principal arterial system, these roads form a rural network that links other cities, larger towns, and other traffic generators, such as major resort areas, capable of attracting travel over long distances; links all developed areas of the state; and serve corridors with trip lengths and travel density greater than those predominantly served by rural collector or local systems. Minor arterials therefore constitute routes whose design should be expected to provide for relatively high overall travel speeds, with minimum interference to throughmovement. (3) Major Collectors. These roads, with minor collectors, primarily serve the county rather than state traffic. Consequently, more moderate speeds are typical. They serve any county seat or larger town not on an arterial route, and other traffic generators of equivalent intra county importance, such as consolidated schools, shipping points, county parks, and important mining and agricultural areas; link the latter places with nearby larger towns or cities, or arterials and freeways; and serve the more important intra county travel corridors Pickens County UDSO: Amended 2/16/10

15 Sec Streets. (4) Minor Collectors. Serving county-wide traffic, these roads should evenly collect traffic from local roads and bring all developed areas within a reasonable distance of a collector road; provide service to the remaining smaller communities; and link the locally important traffic generators with the hinterland. (5) Local Roads. These roads serve primarily to provide access to adjacent land and serve lowmileage trips as compared to collectors or other higher systems. Local roads constitute the rural mileage not classified as part of the principle arterial, minor arterial, or collector systems (c) Relation to present and future street system. (1) The street pattern within a development or subdivision shall provide for the continuation or appropriate projection of the existing street pattern or anticipated development, if any, at the same or greater width, but in no case less than the required minimum width. Topography, natural features such as streams and tree growth shall be considered. (2) Existing streets that adjoin a development or subdivision boundary shall be deemed a part of the subdivision. The proposed street system within a subdivision shall have the right-of-way of existing streets extended no less than the required minimum width. Subdivisions that adjoin only one side of an existing street shall delineate one-half of the additional right-of-way needed to meet the minimum width requirement for the street. If any part of the subdivision includes both sides of an existing street, all of the required additional right-of-way shall be delineated. (3) If the county desires the roadway to be improved to a standard greater than that for a local residential rural roadway, Pickens County shall provide or pay the cost of the additional materials and labor. (4) All right-of-way required for off-site improvements shall be acquired by the developer at no expense to Pickens County. If the Developer is unable to acquire the right-of-way, the Pickens county attorney shall initiate acquisition proceedings, at the expense of the developer, after authorization by the Pickens County Council (5) Where, in the opinion of the County Engineer, it is necessary to provide for interparcel access to adjoining property, proposed streets shall be extended by delineation of right-of-way to the boundary of such property and existing streets through the development. (6) Subdivisions shall be laid out so as to discourage through traffic on local streets. However, the provision for the extension and continuation of arterial and collector streets into and from adjoining areas is required. (7) Where a subdivision abuts or contains an existing or proposed arterial street, the County Engineer shall require marginal access streets, single tier lots, or such other treatment as will provide protection for abutting properties, reduction in the number of intersections with the arterial street, and separation of local and through traffic. (8) Where no street exists or where the adjoining property is in alignment with a proposed street, a temporary turnaround shall be provided at the boundary of the property. Pickens County UDSO: Amended 2/16/

16 Sec Streets (d) Design standards for streets. (1) Arterial Streets. All State or U.S. numbered highways shall meet all design requirements of and be approved by the South Carolina Department of Transportation. All County arterials that are not State or U.S. numbered highways shall meet all design requirements of this Development Ordinance. (2) Local and Collector Streets. All local and collector streets shall comply with the design and construction requirements of this Development Ordinance, except that all State or U.S. numbered highways and roadways shall meet all design requirements of and be approved by the South Carolina Department of Transportation. Traffic calming devices, when warranted, shall be installed in all residential and commercial developments. The County Engineer must approve the installation of any calming device. (3) Minimum width of right-of-way. Table 10.2: Minimum Right-of-Way Width Minimum width of right-of-way Width of Rightof-way measured from lot line to lot line Street Classification shall be as shown on Table Additional right-of-way may be Arterial Street* Set by SCDOT required to accommodate turn Major Collector Street* Set by SCDOT lanes, deceleration lanes or other Minor Collector Street Set by SCDOT road improvements. Local Commercial or Industrial Street 66 feet (4) Additional Right-of-Way. Local Residential Street w/swale ditches 50 feet Local Residential Street w/curb & gutter 50 feet a. Subdivisions which include an existing street that does not conform to the minimum Alleys 24 feet right-of-way requirements of this Ordinance shall provide additional width along one or both sides of such street or road so that the minimum right-ofway required by this Article is established if lots front on the existing street. Subdivisions abutting only one side of such a street or road shall provide a minimum of one-half of the right-of-way required by these regulations measured from the center of the existing right-of-way. b. When a future street or road, as proposed in the Comprehensive Plan or otherwise delineated by County Council, adjoins or traverses the subdivision or development project, the future right-of-way shall be platted as part of the subdivision or development project. No development will be allowed within the platted future right-of-way except for drives and landscaping, and the platted future right-of-way is to be treated as a lot line for the provision of all setback lines as required by this Article. c. When warranted by topography or other utility placement, on local residential streets with a 50 foot right-of-way, additional property for a permanent utility maintenance easement shall be established adjacent to the right-of-way. (5) Vertical alignment of streets. a. All streets shall have a minimum centerline grade of 1.0 percent. Minimum grade on cul-de-sacs shall be 1% Pickens County UDSO: Amended 2/16/10

17 Sec Streets. b. Minimum design speeds and maximum grades for proposed streets by Table 10.3: Street Grades and Design Speed street classification shall be as shown on Table Design exceptions must be Street Type Arterial street Maximum Grade Per SCDOT Minimum Design Speed Per SCDOT justified and Major Collector street* Per SCDOT Per SCDOT approved by the Minor Collector Street Per SCDOT Per SCDOT County Engineer. Local Street 14% 25 mph c. Vertical curves Alleys Varies Varies intersecting tangents of less than 10% shall use a K factor of 16 for a crest vertical curve and a factor of 24 for a sag vertical curve. This shall be valid for a speed limit of twenty- five miles per hour or less. Centerline tangents intersecting greater than 10% shall be approved by the County Engineer on a case by case basis, with sight distances being the major determining factor. (6) Horizontal alignment of streets. a. All horizontal curves shall have a minimum radius of one hundred seven (107) feet. Where a deflection angle of more than ten (10) degrees in the alignment of the street occurs, the right-of-way shall be curved (see Figure 10.1). Figure 10.1 Horizontal Curves b. Reverse curves in the street right-of-way should be avoided but may be approved by the county engineer at his discretion (see Figure 10.2) Figure 10.2 Reverse Curves Pickens County UDSO: Amended 2/16/

18 Sec Streets. c. Street jogs shall have a centerline offset of no less than as shown in the following table and figure: Table 10.4 Intersection Offset SPEED LIMIT ON MAIN THROUGH STREET OFFSET IN FEET 25 Miles Per Hour 125 Feet 35 Miles Per Hour 150 Feet 45 Miles Per Hour 175 Feet 55 Miles Per Hour 200 Feet Figure 10.3 Intersection Offsets d. Intersections. All streets shall intersect at no less than 75 degrees, and as near a right angle as possible. The angle of intersection is to be measured at the intersection of the street centerlines. Such intersecting streets shall provide an uninterrupted line of sight from the center point of the intersection for not less than the minimum sight distance required in accordance with this Development Ordinance. e. Multiple intersections involving the junction of more than two streets shall be prohibited unless otherwise approved by the County Engineer. f. Curb lines at street intersections shall have a radius of curvature of not less than 25 feet. Where the angle of street intersection is less than 90 degrees, a longer radius may be required. g. Intersecting street right-of-way lines shall parallel the back of curb of the roadway, and shall be mitered 20 feet along both streets from the point of the right-of-way lines projected to their intersection. See Figure Pickens County UDSO: Amended 2/16/10

19 Sec Streets. Figure 10.4 Mitered Right-of-Way (7) Minimum sight distance. a. Sight distance requirements at intersections and driveways shall be as shown on Table In general, the sight distance requirement is equal to 10 times the posted speed limit or is equal to the latest SCDOT adopted Table 10.5: Minimum Sight Distance standard. b. The design speed for Design Speed Distance in Feet (Each Way)* sight distance requirements at entrance intersections shall be the existing posted speed limit c. Distances shall be measured from a point on the centerline *Or equal to the latest SCDOT adopted standard. of the entering road or driveway 15 feet back from the edge of the nearest trafficway in the abutting street, and extending in both directions along the abutting street. 1. Minimum sight distances are to be measured from the driver s eyes, which are assumed to be 4.50 feet in height above the pavement surface, to an object 6 inches high on the pavement in the center of every oncoming travel lane. 2. The sight distance shall be clear along its entire minimum length and unimpaired by intervening changes in street grade, horizontal alignment or obstructions. Examples of obstructions are vegetation, ground cover, signs, existing topography, etc Pickens County UDSO: Amended 2/16/

20 Sec Streets. Figure 10.5 Sight Distance (8) Dead-end streets (cul-de-sacs). a. Cul-de-sac length. 1. A cul-de-sac shall be no more than 2500 feet long unless necessitated by topographic or other conditions and approved by the County Engineer. 2. Where a cul-de-sac street exceeds 2500 feet in length, the County Engineer shall require one or multiple interim turn around(s) to be provided. Figure 10.6 Interim Turn-Arounds 3. A cul-de-sac street shall have a length of no less than 125 feet Pickens County UDSO: Amended 2/16/10

21 Sec Streets. 4. The length of a cul-de-sac shall be the distance along the centerline of the cul-de-sac street measured from the centerline of the intersecting street to the center point of the turnaround radius. 5. Other cul-de-sac designs may be considered by the County Engineer on a case by case basis. b. Turnaround dimensions. 1. Cul-de-sacs in residential subdivisions shall terminate in a circular turnaround having a minimum right-of-way of at least 50 feet in radius, and a paved turnaround with a minimum outside radius of 40 feet. Figure 10.7 Cul-de-sac Dimensions 2. Cul-de-sacs in commercial and industrial subdivisions shall terminate in a circular turnaround having a minimum right-of-way of at least 100 feet Pickens County UDSO: Amended 2/16/

22 Sec Streets. in radius, and a paved turnaround with a minimum outside radius of 80 feet. c. A dead-end street other than a cul-de-sac shall not be allowed except as a temporary stage of construction of a street that will be extended in a later stage of construction. Such a temporary dead-end street shall be provided with a temporary turn-around having a roadway radius of 40 feet if: 1. one or more lots front exclusively on the street; and, 2. extension of the street is not under construction when the Final Plat is submitted for recording. 3. Temporary turnarounds shall consist of 3 inches of graded aggregate. (9) Alleys and service drives. a. Alleys may be required at the rear of all lots used for multi-family, commercial or industrial developments. b. Alleys in residential subdivisions shall not be permitted, unless the alleys are intended to provide rear-access to garages on each lot. c. When allowed, dead-end alleys shall be provided with a turn-around having a radius of at least 40 feet, a T-head turn-around, or other solution acceptable to the County Engineer. (10) Half streets prohibited. Half streets are prohibited. Whenever a street is planned adjacent to the proposed subdivision tract boundary, the entire street right-of-way shall be platted within the proposed subdivision. (11) Split Level Streets and One-way Streets. Streets which are constructed so as to have two trafficways, each at a different level within the same right-of-way, shall provide a paved traffic surface of at least 16 feet on each level and a slope between the two trafficways of not less than three to one. One-way streets and split streets will be allowed when: a. Topographic conditions are such that alternatives to the typical street construction would be more desirable. b. The shape and size of the parcel could be more efficiently developed. In either case, approval must be obtained from the Engineering Department for the specific design. (12) Intersection islands. Islands at intersections and the placement of signs within the right-of-way shall be subject to individual approval by the County Engineer. The following criteria shall be met in the construction plans of such intersections: a. Additional right-of-way must be provided to accommodate the divided intersection of island so as to meet all other requirements of this ordinance. b. No type of sign or other construction will be located within ten (10) feet horizontally from the road right-of-way of the connecting road. In the event the connecting road has no right-of-way, an assumed right-of-way of twentyfive (25) feet from the centerline shall be applied. c. A concrete curb shall be constructed around the inside perimeter of the island. This curb shall be located four (4) feet horizontally from any sign or structure on all sides Pickens County UDSO: Amended 2/16/10

23 Sec Streets. d. The paved roadway on each side of the island shall have a usable paved width of not less than sixteen (16) feet. e. The centerline of intersecting streets shall be a minimum of one hundred fifty (150) feet beyond the end of the entrance island. No taper shall be allowed across the width of intersecting roadways. f. No driveway curb cuts shall be allowed within five (5) feet of the end (rear) of the entrance island. g. There shall be one hundred (100) feet of tangent roadway separating the entrance from a curve in the roadway. h. The front of the island shall not encroach upon the intersecting right-of-way and shall not be more than ten (10) feet from the same right-of-way. i. Islands shall be properly underdrained. Figure 10.8 Subsurface Drainage Figure 10.9 Entry Island Layout Pickens County UDSO: Amended 2/16/

24 Sec Streets. Figure Island Detail Pickens County UDSO: Amended 2/16/10

25 Sec Streets. (13) Intersections and Driveway Grades All streets and driveway shall provide a maximum grade of five (5) percent for a distance of twenty (20) feet from the edge of pavement at any intersection (see figure 10.11) Figure Intersection/Driveway Grades 1010 (e) Street Improvements Roadways shall be constructed and paved with top courses meeting the following standards: (1) Minimum width of pavement. a. The minimum pavement width, measured from edge of pavement to edge of pavement, shall be as required for the street type as shown in Table 10.5 as well as in the design details. (2) Street base. a. Graded aggregate base course. The base course shall consist of mineral aggregate and may be a combination of natural deposit or a blend of the materials specified. All materials are subject to approval by the County Engineer. b. Street base material shall conform to the thickness as required for the street type in the Table 10.5 as well as in the design details.. c. For streets without curbs, the base shall extend at least 1 foot beyond the edge of payment. d. Wherever unsuitable material is found in the subgrade, the unsuitable material shall be replaced with graded aggregate stone. (3) Pavement topping. a. Prime. After the base has been placed, mixed, compacted, shaped, inspected and accepted, it shall be primed with suitable asphaltic materials as specified by the County Engineer. b. Roadway binder. After the prime has been inspected and accepted, the roadway or street shall be surfaced with Type B binder as required for the street type on Table c. Tack coat shall be applied on a prepared road surface according to the requirements of the County Engineer and the current standards of SCDOT. Pickens County UDSO: Amended 2/16/