Pavement - Asset Sustainability Ratio

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Asset Sustainability Ratio

Performance analysis

2022

Asset Sustainability Ratio

The Asset Sustainability Ratio is a measure that reflects the level of asset replenishment that is being invested into the pavement network. If the value is equal to or above 1.0, sufficient investments are being made to ensure the pavement assets are sustained and preserved into the future.

WSDOT's long-term pavement performance measures continue to worsen in 2022

In 2022, the Asset Sustainability Ratio continued to worsen because the investments to preserve WSDOT-managed pavement continue to be far less than what is needed to keep it in serviceable condition.

WSDOT pavement assets have had an ASR of less than 1.0—indicating insufficient funding for pavement asset sustainability—for the past five years. In 2022, the ASR for WSDOT pavement assets was at an all-time low of 0.47 down 0.02 points from 0.49 in 2021.

The ASR is calculated by determining the years of pavement service life added to the network in a given year divided by the pavement service life consumed during the same year. If the ASR is less than 0.50—as it was in 2021 and 2022—then the years of pavement service life added to the system (by improving pavement condition) are less than half of the pavement life consumed (by usage and aging).

2021

WSDOT's long-term pavement performance measures continue to worsen in 2021

In 2021, WSDOT was not preserving enough pavement to replenish what was used, and the backlog of pavement needing repair continued to grow.

WSDOT pavement assets had an Asset Sustainability Ratio below 1.0—indicating insufficient funding for pavement asset sustainability—for four of the past five years (refer to chart below). The average ASR of WSDOT's pavement assets for the past five years was 0.77, which was 14.4% (0.13 points) below the lowest sustainable range of a 0.9 ASR.

The ASR dropped 41.7% from 0.84 in 2020 to 0.49 in 2021 and has had a five-year decrease of 45.6% since 2017.

The ASR is calculated by determining the years of pavement service life added to the network in a given year divided by the pavement service life consumed during the same year. For example, a network of 18,500 lane-miles will consume 18,500 lane-mile years of life by aging one year.

2020

After improving in 2019, WSDOT's long-term pavement performance measures worsen in 2020 Asset Sustainability Ratio declines

In 2020, WSDOT was not preserving enough pavement to replenish what was used, and the backlog of pavement needing repair continued to grow. WSDOT pavement assets were below 1.0—lower than the sustainable range—for four of the past five years.

In 2019, WSDOT had an Asset Sustainability Ratio of 1.01, an improvement of 65.6% over 2018. This was a combined number due to multiple, large, multi-year concrete pavement projects that became substantially complete in 2019 and temporarily raised the ASR. The 2020 ASR dropped 16.8% to 0.84, which means WSDOT continues to fall behind in replenishing the state's roadways.

The ASR is calculated by determining the years of pavement service life added to the network in a given year divided by the pavement service life consumed during the same year. For example, a network of 18,500 lane-miles will consume 18,500 lane-mile years of life by aging one year.

Asset Sustainability Ratio shows insufficient funding

The Asset Sustainability Ratio is a measure that reflects the level of asset replenishment that is being invested into the pavement network. If the value is equal to or above 1.0, sufficient investments are being made to keep the pavement assets sustained and preserved into the future. A value less than 1.0 indicates insufficient funding for pavement asset sustainability

2019

Asset sustainability ratio improves, five-year average still unsustainably low

The Asset Sustainability Ratio is the ratio between years of pavement life added to the pavement network in a given year and years of pavement life the network lost through aging in that same year.

The ASR for WSDOT's pavement network was 1.01 in 2019, reaching its target of being between 0.90 and 1.1, and surpassing 1.0 for the first time since the measure was first calculated in 2011. This ratioindicates that for each year of pavement life used up in 2019, 1.01 years of pavement life were added. While the ASR improved substantially from 2018 (when it was 0.61), the improvement was caused by the completion of several multi-year concrete paving projects. As a result, the 2019 ASR is less indicative of the sustainability of WSDOT's level of investment in pavement preservation than the five-year average.

The ASR measures the sustainability of WSDOT's annual level of investment in the pavement network. If the ASR is below 1.0 for a particular year, then fewer years of service life were added to the pavement network than were consumed. A sustainable level of investment would yield an ASR that averaged 1.0, but varied between 0.9 and 1.1 in any given year. From 2015 through 2019, WSDOT's average ASR was 0.75-indicating an unsustainably low average level of investment over those five years.

2018

Asset sustainability ratio declines in 2018, falling out of sustainable zone

The Asset Sustainability Ratio is the ratio between years of pavement life added to the pavement network in a given year and years of pavement life the network lost through aging in that same year.

The ASR for WSDOT's pavement network was 0.61 in 2018, failing to reach its target of 0.90-1.1, and indicating that for each year of pavement life used up in 2018, 0.61 years of pavement life were added. This represents a drop from 2017, when projects supported by the 2015 Connecting Washington funding package temporarily increased the level of pavement preservation work completed and brought the ASR to 0.9—the first time the ASR reached the sustainable zone since it was first calculated in 2011.

The ASR measures the sustainability of WSDOT's annual level of investment in the pavement network. If the ASR is below 1.0 for a particular year, then fewer years of service life were added to the pavement network than were consumed. A sustainable level of investment would yield an ASR that averaged 1.0, but varied between 0.9 and 1.1 in any given year. From 2014 through 2018, WSDOT's average ASR was 0.66—indicating an unsustainably low level of investment. The results of this low level of investment are reflected in the declining condition of WSDOT's pavement network

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