Bridges - Steel bridges

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Steel bridges

Source: WSDOT Bridge and Structures Office.

Performance analysis

FY2024

Square footage of steel surface on bridges due or past due for painting increases 22.7% from June 2023 to June 2024

As of June 2024, WSDOT had 59 steel bridges (with 2.9 million square feet of steel surface area) past due for painting, and had 44 (with 5.2 million square feet of steel surface area) due for painting.

The June 2024 total of approximately 8.1 million square feet of steel either due or past due for painting these 103 bridges marks a 22.7% increase from June 2023, when approximately 6.6 million square feet of steel surface area on 102 bridges was either due or past due for painting.

Over the past five years, the number of bridges due or past due for painting has decreased by 2.8% from 106 in June 2020 to 103 in June 2024. However, the square footage of steel surfaces on bridges due or past due for painting increased by 3.8% from June 2020, when approximately 7.8 million square feet were either due or past due for painting, to June 2024, when this figure reached approximately 8.1 million square feet.

WSDOT classifies steel bridges as due for painting when between 2% and 5% of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting. The paint is expected to last 20 to 30 years under normal conditions.

FY2023

Square footage of steel surface on bridges due or past due for painting decreases 18.5% from June 2022 to June 2023

As of June 2023, WSDOT had 55 steel bridges (with 2.7 million square feet of steel surface area) past due for painting, and 47 (with 3.9 million square feet of steel surface area) were due for painting.

The June 2023 total of approximately 6.6 million square feet of steel either due or past due for painting the 102 bridges marks an 18.5% decrease from June 2022, when approximately 8.1 million square feet of steel surface area on 108 bridges was either due or past due for painting.

The decrease in the number of bridges due for painting and for the increase in the number of bridges past due for painting is attributed to recent modifications that WSDOT made to its criteria for determining bridge painting needs. The new criteria places more emphasis on paint condition and less emphasis on the age of the paint.

Over the past five years, the number of bridges due or past due for painting has increased by 3% from 99 in June 2019 to 102 in June 2023.

WSDOT classifies steel bridges as due for painting when between 2% and 5% of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting.

FY2022

Square footage of steel surface on bridges due or past due for painting decreases 10.0% from June 2021 to June 2022

As of June 2022, WSDOT had 43 steel bridges (with 4.0 million square feet of steel surface area) past due for painting, and 65 (with 4.1 million square feet of steel surface area) were due for painting.

The June 2022 total of approximately 8.1 million square feet of steel either due or past due for painting the 108 bridges is a 10.0% decrease from June 2021, approximately 9.0 million square feet of steel surface area on 107 bridges was either due or past due for painting.

WSDOT also had three steel bridges (with 147,946 square feet of steel surface area) under contract to be painted as of June 2022. This was the same number of bridges that were under contract in 2021. The new paint is expected to protect the steel for another 25 years.

Over the past five years, the number of bridges due or past due for painting has increased by 9.1% from 99 in 2018 to 108 in 2022. WSDOT classifies steel bridges as due for painting when between 2% and 5%of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting.

FY2021

Square footage of steel surface on bridges due or past due for painting increases 14.7% from June 2020 to June 2021

As of June 2021, WSDOT had 50 steel bridges (with more than 5.4 million square feet of steel surface area) past due for painting, and 57 (with more than 3.5 million square feet of steel surface area) were due for painting.

The June 2021 total of approximately 9.0 million square feet of steel either due or past due for painting the 107 bridges is a 14.7% increase from June 2020, when 7.8 million square feet of steel surface area on 106 bridges was either due or past due for painting.

WSDOT classifies steel bridges as due for painting when between 2% and 5% of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting.

The total number of steel bridges either due for painting, past due for painting or under contract to be painted was similar in June 2017 (109) and June 2021 (107). However, there were 38.9% more bridges past due for painting in June 2021 (50 bridges) than in June 2017 (36 bridges; refer to chart above). WSDOT also had three steel bridges (with 127,250 square feet of steel surface area) under contract to be painted as of June 2021. The new paint is expected to protect the steel for another 25 years.

WSDOT classifies steel bridges as due for painting when between 2% and 5% of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting.

FY2020

WSDOT expects to paint 10 of its 116 steel bridges due or past due for painting by the end of the 2019-2021 biennium

As of June 2020, 47 WSDOT-owned steel bridges (with 4.1 million square feet of steel surface area) were due for painting, while 59 (with 3.7 million square feet of steel surface area) were past due. The total of 7.8 million square feet of steel either due or past due for painting is an increase from June 2019, when 7.0 million square feet of steel surface area on 99 bridges was either due or past due for painting (see chart below). WSDOT classifies steel bridges as due for painting when between 2% and 5% of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting.

The total number of steel bridges either due for painting, past due for painting or under contract to be painted was similar in June 2016 (112) and June 2020 (116); however, there were 51% more bridges past due for painting in June 2020 (59 bridges) than in June 2016.

WSDOT also had 10 steel bridges (with 1.6 million square feet of steel surface area) under contract to be painted as of June 2020. These 10 bridges were the only steel bridges WSDOT expected to be able to paint during the remainder of the 2019-2021 biennium. All 10 were steel truss bridges, and six were on T-1 freight corridors. The average age of the paint on these bridges was 25 years. The new paint being applied was expected to protect the steel for another 25 years.

WSDOT classifies steel bridges as due for painting when between 2% and 5% of their steel surface area is exposed; when more than 5% of a bridge's steel surface area is exposed, it is classified as past due for painting.

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