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Printed on:Monday 10/14/2024 12:40 PM 29C0393/AAAS/136929Pageof3 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 8 UNDERWATER INVESTIGATION DETAILS - NOT APPLICABLE FOR THIS BRIDGE. STEEL INVESTIGATION DETAILS SCOPE AND ACCESS All elements were accessible by foot on and around the structure. There was up to 3 feet of water in the creek between Bents 24 and 25 during this investigation. No elements were submerged. All visible elements were fully inspected. A complete routine inspection was performed. DECK AND ROADWAY There is vegetation growing over the left and right rails at several locations. (See Photo 2 dated 06/09/2022). This condition has been previously reported and no significant changes were noted. The AC approach pavement near Abutment 28 was repaved up to 3 feet longitudinally since the last routine inspection. The new pavement has smoothed out the previously reported settlement. See Photo 1. WATERWAY There is a 12 foot wide x 12 foot long x 3 feet deep scour hole Span 8 side of Bent 9 around Column 4. See Photo 4 dated 06/09/2022. The previously reported debris build-up on Bents 23 and 24 has washed away. There is a small amount approximately 1 cubic yard remaining around Column 3 at Bent 23. See Photo 2. There is grouted rock rip-rap throughout Spans 23 to 25 underneath the structure. See Photo 2. In addition, stacked gabion rock baskets have been placed on each span side of Bent 24 columns and the Span 24 side of Bent 25 columns. (See Photos 3 and 4 dated 06/22/2020). The top of the gabion basket near Column 4 is leaning slightly away from the column. See Photo 4 dated 06/22/2020. The previously reported wire that wraps around the base of each column and is connected to an adjacent gabion basket has been covered with grout and unable to monitor during this investigation. (See Photo 21 dated 10/24/2014). This condition will be monitored during future inspections. During the 10/17/2012 routine inspection, the Abutment 28 diaphragm was undermined 8 inches vertically and 28 inches horizontally with 4 exposed foundation piles. Rock slope protection has since been placed on the Span 27 embankment between Bent 27 and the abutment face. (See Photo 22 dated 10/24/2014). The undermined portion of the abutment diaphragm has been filled in with loose rock and the exposed piles are no longer visible for inspection. See Photo 23 dated 10/24/2014. This structure was determined to be scour critical in the 01/18/2007 Hydraulic Report and reaffirmed on 08/21/2018 with a NBI Item 113 code of 3. An updated Bridge Scour Evaluation - Plan of Action form dated 07/14/2021 is on file. The current plan calls for regular monitoring of the waterway during routine inspections every 24 months, closure of the structure if water elevations reach 100 year flood stage and monitor the deck elevations annually and after 100 year storm event. Several channel section measurements were taken during this investigation and compared to the previous stream section dated 08/21/2018. The results of that comparison indicate that there have been no significant changes. The channel has been relatively stable with no significant degradation, aggradation or migration. INSPECTION COMMENTARY - NOT APPLICABLE FOR THIS BRIDGE. CONDITION INFORMATION SPECIAL INSPECTION INFORMATION