02.24.2025 PW SS Briefings - Laserfiche WebLink

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INSPECTION PROGRAM, FINDINGS AND RECOMMENDATIONS Bridge inspections are performed in accordance with the National Bridge Inspection Standards(NBIS)and Title 23 CFR 650.3. The standards mandate that all public agencies with a bridge inventory inspect and report the findings at a minimum of once every 24 months (routine inspection). Special inspections are required for bridges that cannot be given close or adequate inspections from the ground. Steel bridges with non-redundant steel tension members (NSTM), previously known as fracture critical members, may also require special inspections with specialized equipment. Another category of special inspections includes Underwater inspections which are required every five years for bridges with piers that extend below ordinary low-water levels. The inspector uses these standards to document the current condition of each bridge element listed.The deficiencies are coded to the NBIS and show degree of deterioration in various elements. The three primary elements are the deck,superstructure,and substructure.As deterioration accelerates,the coding values are adjusted accordingly. In the case where the coding factors are extremely low, recommendations are made for replacement or rehabilitation of the structure. Bridges with identified deficiencies may be inspected or monitored at more frequent intervals.The results of our inspection program are forwarded to the Washington State Department of Transportation(WSDOT) Local Programs Office for review. Once the report has been reviewed by WSDOT, it is available for the Federal Highway Administration (FHWA) and others to use. A copy of all final inspection reports are maintained on file at Kittitas County Public Works. There are other factors that go into determining the overall health of a bridge. Sufficiency Rating(SR) is a score calculated based on a multitude of factors that are reviewed by the inspector. The SR is a number from 0 to 100,with 100 being an entirely sufficient bridge,and 0 being an entirely insufficient or deficient bridge,as defined by FHWA. Items that go into the determination of the SR,include load bearing capacity, average daily traffic,availability and length of detour,the geometry of the bridge,and the scour action of bridges passing over a waterway. Only structurally deficient (SD) bridges with a sufficiency rating of less than 40 are eligible for replacement funding through the WSDOT bridge program. Bridges with a sufficiency rating of less than 80 are eligible for rehabilitation funding through WSDOT bridge program. As of December 31, 2023, the County has 58 bridges that are eligible for replacement or rehabilitation funding. The bridge inspection program recognizes that with limited funding, it is important to identify trends that are affecting the deficiencies of our bridge structures, such as age and materials used in construction. Kittitas County Public Works continually applies for available funds to assist with deficient bridges that are eligible for Federal Highways Bridge Program funds and Surface Transportation Program funds as well as other sources. County bridges not eligible for Federal funds, such as short-span bridges 20-feet in length or less, have their replacement/rehabilitation needs prioritized by Public Works staff, based on structural deficiency, resource availability, and the County Commissioners' authorization to fund the project in the Transportation Improvement Plan. Similarly, for maintenance, repair, and minor rehabilitation work, prioritization is based on County bridge maintenance funds and staff availabilities. Kittitas County does not have any bridges on designated truck freight routes with a T-1 orT-2 classification. T-1 freight routes are defined as carrying more than 10 million tons per year.T-2 freight routes are defined as carrying more than 4 million and less than 10 million annual gross tonnage and serve as a portion of the State transportation network. Kittitas County 2024 Annual Bridge Report