Developing Waterways Asset Management Program that Incorporates Differences between Highly Urban and Semi-Urban or Rural Watersheds in Risks and Management Strategies
The principles of Asset Management, have traditionally been applied to Water, wastewater, and transportation Utilities and focused on constructed physical assets. Yet, these principles are applicable to all management functions within a utility or organization. In our case, the principles
of asset management have been applied to waterways where the nature of the assets themselves are not all constructed physical structures. The waterways asset management plan we have developed captures conditions along linear assets (streams and channels), including certain natural and constructed
assets that can be rehabilitated and maintained to last over an infinite period of time. It captures differences between waterways that are required to support certain specifies of habitat that are of concern and others that do not.
To enable analysis of assets by geographic location and
asset categories, it is necessary to create an asset register which is a database of assets. It requires a unique ID to be created for each asset in each database in which the asset is recorded and cross referencing the IDs; also it requires an intelligent ID that describes the geographic
location of the asset based on its position within an asset hierarchy and the type of asset. The register also contains the set of attributes that can describe the condition of the asset.
Asset Management program can be used to monitor the condition of each asset with respect to its level
of service, manage the preventive and corrective maintenance programs, and manage the risks. For waterways and watersheds, it is necessary to involve a multi-disciplinary team of biologists, engineers, scientists, operations specialists and management consultants to identify the different
levels of service for the asset and identify the relevant attributes that would allow the team to measure the probability of failure of the asset to satisfy the levels of service. The levels of service can be for water supply, water utility and watershed operations.
One important facet
of the asset management program is a recognition that of consequence of failure (COF). COF is a concept based on the recognition that not all assets with the same probability of failure (based on the imminent failure mode) pose the same consequence of failure or potential liability. The COF
analysis is based on social (public safety), economic (liability) and environmental (habitat) obligations. Each of the three categories are weighted equally (score of 1 to 5 for each category, totaling a maximum of 15), thereby avoiding bias created by overweighting ecological parameters or
ignoring ecological parameters. The probability of failure, POF (on a 1 to 5 scale) measures where an asset is with respect to its anticipated remaining life. It is integrated with the total COF score to determine the assets business risk exposure (BRE). The BRE score is defined as the POF
A BRE threshold can be established to manage the assets. In this instance, the strategy was based on maintaining assets to a BRE threshold of 40. Corrective and maintenance is to be conducted on assets that exceed this threshold. Preventive maintenance is conducted on those assets
whose BRE would exceed 40 unless the periodic maintenance was conducted. Where multiple management strategies can be developed for an asset, the life cycle cost was analyzed to determine the strategy with the lowest life cycle cost. The time period for life cycle analysis has to include one
replacement or rehabilitation. For natural assets that have an infinite life, the life cycle was extended up to 100 years. The financial strategy was developed to manage assets to a certain risk (BRE threshold) and operate with the lowest life cycle cost across the watershed.
It is also
important that the COF score capture the differences in environmental requirements and liabilities between waterways that need to support certain species of habitat and others that do not. The higher environmental score should apply to those assets in the waterway that affect habitat and not
to all assets within the waterway. This allows the BRE thresholds to be consistent amongst different types of waterways.
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