2018-03-12-minutes-public-works-study-session

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KITTITAS COUNTY DEPARTMENT OF PUBLIC WORKS STUDY SESSION STAFF REPORT STUDY SESSION DATE: March 12, 2018 ACTION REQUESTED: Approve Resolution Authorizing Load Restrictions on Certain County Bridges and Prescribing a Misdemeanor for Violation Thereof 13ACKGROUND: The Federal Highway Administration (FHWA) developed new calculations for determining the weight that a bridge can safely carry following a bridge collapse and, importantly, a recent decision by FHWA to allow heavier trucks on roadways. All state and local governments are evaluating publicly owned vehicle bridges using these new criterion and determining whether additional vehicle weight restrictions must be placed on bridges. Key components of new method: • Added requirement to rate bridge's ability to carry four additional types of "special haul vehicles." These are newly authorized vehicles on roadways that can have heavier loads. • Added requirement to evaluate and rate certain connections on bridges with structural steel members. Public Works coordinated Efforts with KPFF (on call Structural Engineering Consultants) to identify bridges within our inventory that require load ratings in order to comply with the new FHWA mandate. This resulted in 48 bridges that were required to be load rated by December 31, 2017 and 52 bridges to be completed by December 31, 2022. Of the bridges evaluated so far, engineers have determined new vehicle weight restrictions are necessary for 15 bridges. Two additional bridges avoided the posting requirement but will require the shoulders to be restricted with barrier to ensure no loading occurs on the outside of the bridge. As the rest of the bridge inventory is inspected and evaluated, any additional bridges that need restricting will be brought to the Board of County Commissioners for resolution prior to restriction implementation.