Plumas County Municipal Code Art. 6 Road Specifications

(a) Public and private roads shall be built or improved to the specifications set forth in this article.

(b) Any developer, person, or organization which offers for dedication to the public any road shall first improve the road according to the specifications set forth in this article. If new road specifications are enacted after the approval of a development, the County will determine on a case-by-case basis, if requested by the developer, whether those new specifications shall apply to a pending development.

(c) Roads within or required to serve any development, which roads are not offered for dedication to the public, shall be improved by the developer according to the standards for their class and to the specifications set forth in this article. If new road specifications are enacted after the approval of a development, the County will determine on a case-by-case basis, if requested by the developer, whether those new specifications shall apply to a pending development.

(§ 1, Ord. 87-662, eff. June 4, 1987, and § 2, Ord. 04-1014, adopted August 17, 2004)

The width of the right-of-way of all roads outside the Incorporated limits of any city in the County shall be as set forth in Article 5 of this chapter. Additional width may be required to accommodate cuts and fills.

(§ 1, Ord. 87-662, eff. June 4, 1987)

The width of clearing of the right-of-way shall be the width of the roadbed plus the width of cuts and fills plus the clearing limit, all as set forth in Article 5 of this chapter, except that public safety may require the removal of dead or dying trees beyond the limits of construction. The minimum clearing limit may be waived for the preservation of individual trees that are of exceptional size or beauty, but under no circumstance will any trees be allowed within three (3') feet of the edge of traveled way. All due consideration shall be given to the protection of trees from damage during construction. In flat land, the clearing limit shall be measured from the bottom of the ditch. Disposal, including chipping, burying, burning or removal to a landfill site approved by the County, of flammable vegetation and fuels removed during road construction shall be completed before completion of road construction.

(§ 1, Ord. 87-662, eff. June 4, 1987, as amended by § 1, Ord. 91-762, eff. October 3, 1991; § 1(Exh. A), Ord. 2018-1114, adopted October 9, 2018)

(a) The widths of roadbeds, shoulders, pavement and clearing limits shall be set forth in Article 5 of this chapter, dependent upon the classification of the road and projected ADT.

(b) In addition, the requirements set forth in this section shall be met.

(c) The roadbed shall be in the center of the right-of-way except where excess width of right-of-way is required to accommodate cuts or fills, or where in the opinion of the Director of Public Works topography precludes the desirability of the required coincidence, or where it is desirable to preserve individual trees of exceptional size or beauty.

(d) The geometric design of roadbeds shall be such as to accommodate a minimum speed of twenty-five (25) miles per hour, except the minimum design speed for rocked surfacing shall be fifteen (15) miles per hour and the minimum design speed for major thoroughfares shall be thirty (30) to fifty (50) miles per hour, in accordance with engineering practice. An additional surface width of four (4') feet shall be added to curves of fifty (50) to 100 feet radius, and two (2') feet shall be added to curves of 100 to 200 feet radius.

(e) The length of vertical curves in roadways, exclusive of gutters, ditches, and drainage structures designed to hold or divert water, shall not be less than 100 feet.

(f) Roadway grades shall not exceed seven (7%) percent for public roadways and thirteen (13%) percent for private roadways, except with written permission of the Director of Public Works and either the chief of the appropriate structural fire protection agency or, if the roadway is not within the boundaries of such an agency, the designated representative of the California Department of Forestry and Fire Protection (CALFIRE). Roadway grades shall not exceed sixteen (16%) percent.

(g) All gutters, drains, culverts and bridges shall be installed as shown on the approved plans. All bridges, culverts, and other appurtenant structures which supplement the roadway bed or shoulders shall be constructed to carry at least the maximum load and provide the minimum vertical clearance as required by Vehicle Code Sections 35250 through 35252 and 35550 through 35796, with a minimum design vehicle loading as per the American Association of State and Highway Transportation Officials Standard Specifications for Highway Bridges, 17 th Edition, published 2002 (known as AASHTO HB-17), hereby incorporated by reference. All drainage facilities shall have a minimum longitudinal grade of one-quarter percent.

(h) Cut sections shall have a three to one (3:1) side slope between the outer shoulder edge and flow line of the side ditch, and cut and fill slopes shall be two to one (2:1) except where the condition of a cut in rock can be shown to be stable at steeper slopes, in which case the approval of the Director of Public Works shall be required.

(i) The maximum length of dead-end roads, including all dead-end roads accessed from that dead-end, shall not exceed the following cumulative lengths regardless of the number of parcels served:

(1) All lengths shall be measured from the edge of the roadway surface at the intersection that begins the road to the end of the road surface at its farthest point. Where a dead-end road crosses areas of differing zoned parcel sizes, requiring different length limits, the shortest allowable length shall apply.

(2) Where parcels are zoned five (5) acres or larger, turnarounds shall be provided at a maximum of 1,320-foot intervals.

(3) Each dead-end road shall have a turnaround constructed at its terminus.

(j) The roadbed shall have the necessary base material placed and compacted for the full roadbed width, and shall be surfaced for the entire length of the road for a width as set forth in Article 5 of this chapter.

(k) All Class 8 Roads shall connect to a two-lane roadway at both ends, shall not exceed 2,640 feet in length, and shall have a turnout constructed at the approximate midpoint.

(l) Class 11 Driveways exceeding 150 feet, but no more than 800 feet, shall provide a turnout near the midpoint of the driveway. Where a Class 11 Road exceeds 800 feet, turnouts shall be provided no more than 400 feet apart. A turnaround shall be provided at all building sites on driveways over 300 feet in length and shall be within fifty (50) feet of the building.

(§ 1, Ord. 87-662, eff. June 4, 1987, as amended by § 1, Ord. 91-762, eff. October 3, 1991, § 1, Ord. 92-783, eff. July 9, 1992, and § 2, 02-975, eff.; (§ 1(Exh. A), Ord. 2018-1114, adopted October 9, 2018)

Each phase of construction must be inspected by a representative of the Department of Public Works. The phases of construction are: Clearing, grading, subbase, base and paving or surfacing. When the contractor or developer requires such inspection, he shall notify the Department of Public Works of his requirement in writing or by telephone call not less than five (5) working days prior to the time that he would like to have the inspection made, and in advance of starting his next phase of construction. Inspection will be made within three (3) working days after completion of the construction phase requiring inspection.

Written reports on the results of the inspection will be available to all parties concerned within thirty-six (36) hours after the field inspection is made. The contents of the report shall be defined by the Engineering Station, or relationship to street or highway intersections if stationing is not available.

(§ 1, Ord. 87-662, eff. June 4, 1987; and § II, Ord. 06-1046, adopted May 2, 2006; § 1(Exh. A), Ord. 2018-1114, adopted October 9, 2018)

The structural section of the roadbed shall conform to the following thicknesses, or alternative thicknesses, utilizing the California Design Method (R values) and approved by the Director of Public Works:

(a) Clearing of the right-of-way. All objectionable material shall be removed from that portion of the right-of-way to be utilized for construction, including but not exceeding the clearing width set forth in Article 5 of this chapter.

(b) Subgrade. Fill shall be placed and compacted in layers not to exceed eight (8") inches thick. Large boulders, lumps of earth, and other unsuitable materials that will interfere with proper grading and compaction shall be removed and disposed of. Fill material shall be moistened so that a relative compaction of at least ninety (90%) percent is attained. The subgrade shall be crowned two (2%) percent for cross drainage, or as directed by the Director of Public Works.

(c) Culverts. Necessary culverts shall be installed before applying subbase or base rocks, and the backfill shall be compacted to a relative compaction of at least ninety (90%) percent. The minimum size of culvert shall be eighteen (18") inch by eleven (11") inch arch, or fifteen (15") inch round. If concrete culvert pipe is used, that part under the roadbed must be the reinforced heavy wall type. Culverts shall have a minimum cover of twelve (12") inches below the surface. Culverts shall be located and sized in conformance with an engineered drainage plan for the road and shall be constructed to carry the maximum load and provide the minimum vertical clearance as required by Vehicle Code Sections 35250 through 35252 and 35550 through 35796, with a minimum design vehicle loading as per the American Association of State Highway and Transportation Officials (AASHTO) Standard Specifications for Highway Bridges, 17 th Edition, published 2002 (known as AASHTO HB-17), hereby incorporated by reference. All drainage facilities shall have a minimum longitudinal grade of one-quarter.

(d) Subbase course. The subbase course shall be not less than six (6") inches thick and shall extend for the full graded width of the roadbed and for the entire length of the road. The subbase course shall consist of aggregate which meets the following specifications and shall be compacted (rolled) to ninety-five (95%) percent relative compaction:

If preliminary tests show an absence of any rock larger than one and one-half inches in the subbase material, the full eight (8") inches of aggregate may be constructed of the one and one-half inch material.

(e) Base course. The base course shall have a minimum thickness of two (2") inches and shall extend for the full graded width of the roadbed and for the entire length of the street or highway. The base course shall consist of aggregate which meets the following specifications and shall be compacted (rolled) to ninety-five (95%) percent relative compaction:

The base course may be eliminated if the subbase course is eight (8") inches thick and is composed of minus one and one-half inches aggregate.

(f) Reserved.

(g) Paving. Asphalt concrete material shall be applied as follows:

In two (2) separate equal depth lifts. Each lift shall be a compacted depth of .125 feet (1.5 inches). The total depth of the asphalt concrete shall be a minimum of .25 feet (three (3) inches) when compacted to ninety-five (95%) percent relative compaction.

The paving material shall consist of Type B three-fourths-inch maximum medium aggregate, with AR2000, AR 4000 or approved Performance Graded (PG) asphalt. All material and application shall conform to Section 39 of the California Standard Specifications for Highways. Any variation of these requirements must be approved by the Public Works Director.

(h) Reserved.

(i) Field testing costs. Field testing costs which arise from construction or improvements resulting from a development shall be borne by the developer.

(j) Conformance with State specifications. Unless otherwise noted in the specifications set forth in this section, all materials and construction methods shall conform to the current State standard specifications for highways.

(§ 1, Ord. 87-662, eff. June 4, 1987; as amended by § 1, Ord. 96-874, eff. December 5, 1996, § 3, Ord. 04-1014, adopted August 17, 2004; and §§ III—V, Ord. 06-1046, adopted May 2, 2006; § 1(Exh. A), Ord. 2018-1114, adopted October 9, 2018)

(a) All developments directly benefited by a precise planned road, other than a major thoroughfare, must:

(1) Dedicate rights-of-way on-site as necessary to conform to the appropriate standard; and

(2) Pay into the County Road Fund a sum of money equal to the prorated share of the benefit received by the road; or

(3) Construct a portion or all of the road; or

(4) A combination of subsections (2) and (3) of this subsection.

(b) The prorated share of the benefit received by the road shall be calculated in one of the following ways:

(1) The prorated share shall equal the predicted traffic volume on the road arising from the development, divided by the projected traffic volume for the road, and multiplied by the cost of the improvement of the road to the standards for its class, as set forth in Article 5 of this chapter.

(2) The prorated share shall equal the predicted traffic volume on the road arising from the development, divided by the existing traffic volume for the road, and multiplied by the cost of the improvement of the road to the minimum standards for its class, as set forth in Article 5 of this chapter.

(3) The prorated share for development in Commercial, Industrial, or Recreation Areas shall equal the acreage of the development, divided by the Commercial, Industrial, and Recreation Area acreage served by the road, multiplied by the cost of the improvement of the road to the minimum standards for its class, as set forth in Article 5 of this chapter, after the cost of improving the road to the minimum standards for the class it would be if it did not serve any Commercial, Industrial, or Recreation Area is subtracted from the cost of improving the road to the minimum standards for its class. This hypothetical classification shall be based upon the projected traffic volume for the road and the provisions of Article 4 of this chapter.

(4) The prorated share shall equal the predicted traffic volume on the road arising from the development, divided by the projected traffic volume for the road, and multiplied by the cost of the improvement of the road to the minimum standards for its class, as set forth in Article 5 of this chapter, based upon a specific traffic analysis for the development and roads in the area.

(c) The method used to calculate the prorated share of the benefit received by a road shall be determined by the person or body approving the development. The Director of Public Works shall recommend the method to be used to calculate the prorated share of the benefit received by a road and shall calculate that share.

(d) The cost of improvement shall be based on a cost estimate prepared by the developer's engineer and mutually agreed upon the developer and the Director of Public Works. The cost estimate shall be provided with the project application.

(e) Predicted traffic volume, projected traffic volume and the Commercial, Industrial and Recreation Area acreage served by a road shall be determined as set forth in Article 7 of this chapter.

(f) In the event the developer's prorated share exceeds fifty (50%) percent of the total cost of improvement, the required improvements shall be completed for the subject portion of the road.

(g) It shall be the County's prerogative that whenever any work on an existing County road is to be partially financed by the County, the County may elect to do the work with its own forces. Otherwise the improvement work within a development shall be done by the developer's contractor.

(h) All developments directly benefited by a private road shall make whatever improvements are necessary to bring the road into conformance with the class necessary to serve such developments.

(§ 1, Ord. 87-662, eff. June 4, 1987, as amended by § 1, Ord. 91-762, eff. October 3, 1991)