LARIMER COUNTY RURAL AREA ROAD STANDARDS

CHAPTER 7 – BRIDGES AND MAJOR DRAINAGE STRUCTURES7.1 DESIGN STANDARDSA. All culvert pipe, box culverts, and bridges, for which approval by the Larimer CountyPublic Works Department is required or which may ultimately be maintained byLarimer County shall conform with the following:• AASHTO Standard Specifications for Highway Bridges, or LRFD BridgeDesign Specifications, latest edition and applicable interim versions.• CDOT Standard Plans, M & S Standards, latest edition and revisions• CDOT, Standard Specifications for Road and Bridge Construction, latestedition.• CDOT, Bridge Design Manual, latest editionB. Bridge clear roadway width shall accommodate the full width of the traveled lanesand shoulders of approach roads. Bikeway and pedestrian walkways shall beprovided where required by the Engineer.C. All roadway structures must be designed for a minimum HS20-44 loading.D. CDOT Type 3 Guardrail and Bridge Rail are the minimum requirement whereguardrail is warranted.E. All box culvert and bridge designs shall be done by a registered professionalengineer in the State of Colorado.F. Foundation designs shall be based upon the recommendations of a qualifiedgeotechnical engineer. These recommendations shall be documented in thegeotechnical report.G. Culvert and bridge waterway opening designs shall conform to the parameters of theLarimer County Stormwater Design Standards.H. See Larimer County Stormwater Design Standards for minimum design flowfrequencies.7.2 IRRIGATION COMPANY APPROVAL7.2.1 GeneralAny proposed canal, ditch, or lateral crossing will require the review and signatoryapproval of the affected irrigation company. Design and construction activities must becoordinated with the affected irrigation company so that delivery of irrigation water willnot be adversely impacted and the integrity of the ditch itself will not be jeopardized.7.2.2 Required InformationThe owner’s engineer will notify the affected irrigation company, indicating which ditch isinvolved, the proposed scope of the work, and the preliminary schedule for the project.The owner’s engineer will also obtain the following information from the irrigationcompany:Larimer County Rural Area Road Standards Page 7-1October 22, 2007