PUMP SMARTER, NOT HARDER CHANGING HOW UTILITIES PLAN LIFT STATION UPGRADES FOR MORE RELIABLE (BUSINESS) OPERATIONS

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1 PUMP SMARTER, NOT HARDER CHANGING HOW UTILITIES PLAN LIFT STATION UPGRADES FOR MORE RELIABLE (BUSINESS) OPERATIONS Leslie Jones, PE, BCEE, GHD Inc. Wayne Francisco, GHD Inc. Stuart Rosenberger, Charlotte-Mecklenburg Utility Department Abstract In today s business climate of doing more with less, utilities must maximize the use of their infrastructure assets. Historically, lift stations require a large investment of a utilities budget and staff using out-dated work management practices and reactionary improvements planning. In order to maximize the use of existing lift stations and minimize capital expenditures, utilities must shift from short-term, day-to-day operations to focusing on the long-term life cycle and sustainable performance of their lift stations. This shift towards the development of long term funding strategies and a sustainable asset renewal and replacement planning process is the basis of an Asset Management Plan which many utilities are beginning to undertake. An important component in the development of an Asset Management Plan is Condition Assessment. A condition assessment is the technical review of the physical condition of an asset (i.e. lift station) through the application of an organized, consistent, relevant, and practical set of procedural guidelines to approximate the remaining useful life. Knowledge of the condition of a lift station is necessary to assist in utilities decisions related to maintenance, operations, and renewal. Failure to fully understand a station s current condition and remaining useful life and therefore to take appropriate and timely action - may lead to its premature failure or to the misdirection or mistiming of reinvestment. Unanticipated failure of a lift station often leaves the utility with only one option to get the station back in service emergency replacement. The replacement option can often be the most expensive and time consuming of all options and the associated failure can unduly expose a utility to severe undesired consequences. This paper will describe the Condition Assessment methodology and protocol to provide a utility with a process for the ongoing, systematic, and consistent determination of the physical condition of their lift station assets. This protocol will allow utilities to increase their confidence in making management decisions on where and when to invest limited resources to meet current and future demands on their lift stations. Keywords Lift stations, asset management plan, condition assessment Charlotte-Mecklenburg Utility Department Background The Charlotte-Mecklenburg Utility Department (CMUD) is the water and sewer provider for more than 800,000 people living in the seven municipalities and Mecklenburg County. CMUD operates and maintains two water intakes at Lake Norman and Mountain Island Lake, three water treatment plants that average 100 million gallons a day(mgd), over 4,200 miles of water distribution mains, over 4,100 miles of sewer collection pipelines, 79 wastewater lift stations, and five wastewater treatment plants where an average of 77 MGD of wastewater is treated and discharged each day. In 2006, the City of Charlotte hired GHD to help them establish a common framework for managing assets for all departments and to develop the business case for implementing a cross-business work and asset management (WAM) solution that met the requirements of the City and provided positive benefits for both the City s internal and external customers. The primary objectives of the initial phase included:

2 Build consensus and support at key milestones throughout the project to support the identification and aggregation of WAM business requirements; Develop a common understanding of Asset Management within Business Units; Compile interview data into usable business requirements documents; Isolate and document the corporate business problems associated with WAM; Document potential taxpayer/ratepayer/service provider needs related to availability and usability of appropriate City data; Delineate a set of organizational recommendations in order to define the future state of WAM for the City; and Conduct a transparent and defensible solution selection process that results in the best-fit WAM solution for the City. In 2009, the City moved forward with establishing a work management system for CMUD. The team went through an iterative process analysis and development effort. The team enhanced CMUD s core asset management information system using Azteca Cityworks which is a GIS-based asset management solution that ties work order and service requests to mapped assets. With these enhancements the WAM program: Promotes an understanding of the full life-cycle costs of infrastructure service delivery including economic, social and environmental considerations, Actively records important asset information during the process of executing a work order or inspection, Understand the real depreciation and/or consumption of assets and resultant impacts to serves, and Reduces the business risk exposure to the Department by understanding condition and useful life of critical assets. In 2012, GHD and CMUD completed the initial phase of implementation in the Field Operations Division. All field crews now use Cityworks to track and record their daily routines including maintenance, repair and replacement activities using tablets and desktop computers. Using Cityworks Storeroom module of inventory management, the Field Operations annual inventory process was completed in 93% less time than previous years with greater than 98% accuracy. The inventory process went from a month-long process to a 12 hour day with a completed inventory difference of 0.05% on a $1.35 million inventory. Now that the Field Operations Division, including Lift Stations, has integrated Cityworks into their routines the next step will be to perform asset condition ratings to continue improving operations with more informed business decisions. WAM implementation has now also begun for the Water Treatment and Environmental Management Divisions. Asset Management Philosophy Asset management is about managing physical assets throughout their life cycle so as to achieve the lowest life cycle cost. For too long the industry has focused on capital projects and ignored the renewals, maintenance and operational liabilities associated with those projects over their life. There are many examples of infrastructure failures recently where assets have been allowed to deteriorate to the extent that they can no longer deliver the minimum acceptable levels of service. Many assets, particularly those built during the prolonged periods of development that started after World War II, are reaching the latter stages of their useful lives. Asset management helps to put in place long term strategies for managing those assets through the remainder of their lives, and then renewing them at the right time to continue delivering services that customers expect. After implementing asset management a utility should have an improved ability to answer the five questions that are core to any asset management initiative: 1) Do you know what assets you have, what condition they re in and whether they re performing efficiently and effectively?

3 2) Do you know what levels of service you re aiming to deliver, and how each asset is performing within that context? 3) Are you actively managing risk in order to prioritize and optimize investments in your infrastructure; and, to identify the relative criticality of your assets? 4) Do you have documented operations, maintenance and capital investment plans that reflect what you know about your assets? 5) Do you have long term funding and asset management improvement strategies to enable and sustain service delivery? The 10 Step Asset Management Planning Process The US EPA recommends a ten step process, shown in Figure 1, which enables utilities to implement asset management in their organization and appropriately address sustainable governance of their infrastructure. S ystem Layout; Data Hierarchy, Standards, and Inventory Figure 1: 10 Steps to Advanced Asset Management Condition E xpected Life Assessment Valuation; Life Tables; Protocol; Rating Cycle Costing Decay Curves Methodologies Demand Anal.; Balanced S corecard; Perform. Metrics Develop Asset Registry Assess Condition, Failure Modes Determine Residual Life Determine Live Cycle & Replacement Costs S et Target Levels of S ervice (LOS ) Determine Business Risk ( Criticality ) Optimize O&M Investment Optimize Capital Investment Determine Funding S trategy Build AM Plan FMECA; Business Risk Exp.; Delphi Techniques Root Cause; RCM; PdM; ORDM Confidence Level Rating; S trategic Validation; ORDM Renewal Annuity Asset Mgmt Plan; Policies and S trategy; Annual Budget Purpose of Condition Assessment An important component in development of the Asset Management Plan is condition assessment. Knowledge of the condition of an asset is necessary to assist in management decisions related to maintenance, operations, and renewal. A sound condition assessment program will result in an increase of confidence in making management decisions. A condition assessment is the technical review of the physical condition of an asset through the application of an organized, consistent, relevant, and practical set of procedural guidelines. Application of these guidelines can generate timely, accurate, and useful condition information where such information is key to making good investment decisions about an organization s assets. Condition assessment provides insight into the remaining useful physical life of the asset. Failure to fully understand an asset s current condition and remaining useful life and therefore to take appropriate and timely action - may lead to its premature failure or to the misdirection or mistiming of reinvestment in the asset. Unanticipated failure of an asset often leaves a utility with only one option to get the asset back in service to replace the asset. The replacement option can often be the most expensive of all options and the associated failure can unduly expose the organization to severe undesired consequences depending on the nature and context of the failed asset.

4 Regular condition assessment practice will allow maintenance and renewal strategies to be updated and refined more accurately. With timely knowledge of the condition of its assets, even if failure is imminent, the City will have time to look at options other than replacement and to manage a pending failure in a more timely and cost effective manner. The purpose of developing a Condition Assessment Protocol is to provide a detailed set of written guidelines to determine the physical condition of its infrastructure assets. The protocol provides the understanding and methodology behind the condition assessment process. It guides staff to perform and maintain the condition assessment process even after the completion of the initial project and should be refined, expanded, and improved with the accumulation of experience on the part of staff. Relating Condition Assessment to Residual Life and Business Risk Exposure Condition assessment is itself only a means to an end, namely, the approximation of the remaining useful life of the asset. A determination of remaining useful life or residual life is important for two reasons: 1) What life is left in an asset is all that the asset manager really has to work with, and 2) Condition/residual life provides insight into the probability of failure of an asset. The condition is a key element and is several downstream or subsequent sequential steps that assist the asset manager in rationalizing where and when to invest limited resources in an overall asset portfolio. Asset Failure Modes and Assessment Techniques The performance of an asset relates to the current ability of the asset to meet the current and future demands that will be placed on it. Assets can fail in many different ways but they can be classified to fit in the following modes of failure: capacity, level of service, physical mortality, and financial efficiency. Table 1 below lists the four primary failure modes and includes a description of each. For each of the failure modes (Column 1), an Assessment Technique (Column 3) is listed that is used to assess the performance of the asset against that failure mode. During the assessment of an asset each of the failure modes should be considered in order to make the most cost effective management decision. The allocated management strategy to solve an asset s performance issue will vary depending on the dominant failure mode and requires knowledge of the rate of performance deterioration for each failure mode. Failure Mode Physical Mortality Capacity Level of Service Description and Drivers Asset deterioration reduces performance below an acceptable level Age, Usage, Operational Stresses, Acts of Nature Demand exceeds design capacity Growth and System Expansion Functional and Reliability requirements exceed design capability Regulations, Quality, Safety, Client Service, Noise, Odor Table 1: Primary Failure Modes Assessment Technique Condition Level 1 Staff Knowledge Desktop Delphi Level 2 Intermediate Level Physical Inspection Level 3 Advanced Physical Testing and inspection Capacity Level 1 Staff Knowledge Desktop Delphi Level 2 Desktop Capacity Modeling Level 3 Capacity Modeling with Field Data Function Level 1 Staff Knowledge Desktop Delphi Level 2 Process Assessment Level 3 Strategic Planning Reliability Level 1 Staff Knowledge Desktop Delphi Management Strategy Renewal, O&M Optimization Redesign Redesign, O&M Optimization

5 Failure Mode Financial Efficiency Description and Drivers Cost of Operation exceeds feasible alternatives New Technology, Wear, Spare Parts Assessment Technique Level 2 Desktop Analysis Level 3 Work Order History Efficiency Level 1 Staff Knowledge Desktop Delphi Level 2 Desktop LCCA (Estimated Data) Level 3 LCCA with Field Data Management Strategy Replace Assessment Methodology There are several methodologies that can be used to undertake a condition assessment that have been developed over a number of years. Smart Data Collection strategies have been developed as condition assessment can very quickly become very expensive. Too often, funds are invested in a large assessment effort that is not cost effective - that is, where the same level of decision-relevant information could have been generated at far lower cost. Several techniques can guide a Smart Data Collection strategy. Not all of these techniques are appropriate for all types of assets due the nature of these assets. Description of the Smart Data Collection strategies is provided below. 1. Focus on High Risk Assets - Focus condition assessment efforts on those assets with a high Business Risk Exposure score. These assets are the most critical to sustained performance. 2. Identify the Pareto Problems - Pareto was an economist who coined the 80/20 Rule. He observed that typically 80 percent of problems are often caused by no more than 20 percent of the relevant population. In this context, 80 percent of maintenance work orders are typically generated by only 15 to 20 percent of the assets. It is very important to identify those 20 percent problem assets. 3. Use Statistical Sampling - Statistical sampling can give virtually the same level of decision confidence for far less expenditure than 100 percent assessment. 4. Use Imminent Primary Failure Mode As A Guide - Focus condition data efforts only where condition relates to the relevant management strategy. 5. Step-by-Step Filtering - Deploy a step-by-step approach that filters the number of assets for which higher levels of data and analysis are required. 6. Understand Root Cause - Organize the collection effort around an understanding of the root causes of failure for a specific class or type of assets. This principle goes hand in hand with sampling. 7. Use Valued Judgment Where Funds Are Not Available - Often the budget for condition assessment is far below what could be applied, even using Smart Data Collection techniques. It is not necessary to put the decision process on hold pending future funding - assets do not wait on funding. Instead, fill the temporary field condition data gap with valued judgment derived through a Delphi approach. These seven Smart Data Collection techniques can be combined together to form what is considered to be a very efficient three-step best appropriate practice. The three steps are: Level 1 Basic Level 2 Intermediate Level 3 Advanced Each level is more sophisticated and expensive to undertake than the previous one. This approach is depicted in Figure 2, showing the general steps to be taken at each stage. At each progressive level, the assessment process is applied to fewer assets those that require attention due to their deteriorated condition, and especially those that are critical to the operation of the City and present a high risk of failure and consequence of failure. This process is termed filtering, and is highly efficient as additional resources are applied only to those assets that require attention to meet City objectives, after an initial assessment of all assets has been made.

6 Figure 2: Staged Condition Assessment Program (CAP) Process Level 1 Condition Assessment Staff Knowledge ( Delphi Group Workshops) CAP 1 BASIC All assets CAP 2 INTERMEDIATE Fewer assets CAP 3 ADVANCED Key/critical assets Desktop Review / Photographic Walkthrough Detailed Inspections Specialist Inspections and Techniques - Review asset performance Interview key staff / - Delphi workshop - Use asset age profiles and experience - Identify CAP 2 activities - Complete visual inspections - Record data - Assess criticality - Complete risk / cost assessment - Identify practices, sample basis and costs - Justify budget - Program and implement inspections All Condition Information Acquired The normal first step is to conduct a Delphi group workshop with key staff and assess the assets for each of the failure modes using the Level 1 rating scales. Delphi was developed during the 1960s by the Rand Corporation as a way to converge on a sense of project direction in large and complex systems problems (e.g., ICBM missiles and the space program) where many technical aspects from various disciplines needed to be considered. 'Delphi' group workshops have been used extensively for asset management purposes. Even though asset management techniques have progressed substantially, the data to use in these tools has not. The cost (labor and equipment) of collecting data is significant. 'Delphi' group workshops allow for the rapid collection of this data, though the confidence of this data will be lower than by detailed asset assessments. 'Delphi' Group Workshop Asset Objectives The Delphi group workshops provide a 'best valued judgment' (quickest gains, least cost) of the assessment technique rating scales for the assets in the register. The aim is not to get the most accurate assessment using the sophisticated assessment techniques, but to collect a basic rating of all assets from the staff that knows them best. The Delphi group workshops can be used to collect the following information: Validation of the assets included in the asset register: o Comparisons of the asset register with the knowledge of staff; o Identify missing assets and add to the asset register; o Identify duplications and delete from the asset register. Validation of assets installation and rehabilitation dates: o Identify missing construction dates and add to the asset register; o Update existing dates in the asset register, especially if the asset had been replaced since it was originally installed.

7 Condition Assessment: o Assess the condition of each asset where the operators and engineers have adequate knowledge. Identify other failure modes that may supersede the physical mortality failure mode: o Capacity; o Level of Service; o Financial Efficiency. Level 1 Asset Assessment (Basic) The chosen scale for all the assessment techniques rating scales is from 1 to 5, where 1 is the best and 5 is the worst. As the level of assessment increases, the rating scale remains constant, to allow for the comparison of assets assessed at different levels, however, the accuracy of the assessment will increase with increased level of complexity. This Level 1 rating system is normally used for preliminary inspections or during key staff interviews / Delphi group workshops. Where it is not possible to conduct these Delphi group workshops or no knowledge of the asset exists, an alternative methodology to develop Level 1 condition assessment is to use the asset s age details and predicted effective lives, however, this will result in an assessment of a lower confidence level. Table 2 shows a condition assessment model that is suitable as a Level 1 approach. The description, degree of replacement and maintenance level columns can be used as alternative methods to determine the condition rating. The rating chosen should be the best fit to the descriptors. Table 2: Level 1 Asset Condition Assessment Rating Table Condition Description Degree of Maintenance Rating Replacement 1 New or Excellent Condition 0% Normal Preventive Maintenance 2 Minor Defects Only 5% Normal Preventive Maintenance, Minor Corrective Maintenance 3 Moderate Deterioration 10-20% Normal Preventive Maintenance, Major Corrective Maintenance 4 Significant Deterioration 20-50% Rehabilitation, if Possible 5 Virtually Unserviceable % Replace Summary of Level 1 Assessment Confirm rating tables (1 to 5); Take photos during site visit/walk-through with staff; Build asset register by downloading from asset database to identify all assets for initial inspection if available; Establish checks to ensure uniformity of assessment from different staff; Conduct Delphi group workshops; Identify most imminent major failure mode for each asset; Review available work order data; Develop initial assessments; Use photos and work order data to supplement judgment. Input data to the appropriate software system for the analysis of each asset group. If software is not available, then a spreadsheet should be developed; and Undertake a Business Risk Exposure evaluation or criticality assessment to filter assets and identify those assets for Level 2 assessment. This schedule should be reviewed in a Delphi group workshop or interview for amendment, finalization and adoption.

8 Level 2 Condition Assessment Intermediate Inspection Program This stage involves the completion of intermediate - level assessments of the higher-priority assets identified after the completion of the Business Risk Exposure assessment and filtering. The purpose of Level 2 is to undertake a more detailed assessment of the assets through physical inspection and observation. The Level 2 process involves the enhancement of the City s ability to more effectively rank those assets that constitute a significant problem (e.g., condition scores, 3, 4, and 5 (particularly 4 and 5) from the Level 1 assessment). Filtering of assets to determine those required for Level 2 assessments will be based on the assets identified in the Level 1 as in the worst condition and in the risk filtering as those assets representing the highest Business Risk Exposure. For lift stations, a Level 2 visual inspection would include detailed inspection of the pump, motor and piping looking for signs of corrosion and damage, and non-destructive testing to detect cracking and/or voids and weld integrity. A sample Level 2 Condition Assessment Rating Table for pumps is shown in Table 3. Table 3: Level 2 Condition Assessment Rating Sample for Conventional Pumps Conventional Pumps Inclusion: Dry well & line shaft pumps Dosing Pumps A B Aspect Distress Mode Rating Rating Rating Rating Rating CONDITION ASSESSMENT Structure Leakage Appears as new. Minimal moisture on Water dripping from Water pooling on floor Water squirting/ running Appearance seals/joints. seals/joints. onto floor. Shaft, Supports, Bearing Deterioration Shaft & supports sound - no shaft distortion or deterioration evident. Minor shaft/ support deterioration evident, no impact on the structural strength or function. Shaft distortion or bearing/housing wear evident, little impact on structural integrity or function. Shaft distortion or bearing/housing wear evident and has impacted on asset integrity or function. Significant shaft distortion or bearing/housing wear evident, high probability of fracture or failure. C Use Motor Hours Run < 10,000 > 10,000 > 50,000 > 100,000 > 200,000 Symptons D Vibration No unusual vibration detectable Minor vibration detected Moderate vibration Considerable vibration (wristwatch shakes) Major vibration E Temperature No unusual temperature detected Minimal heat from casing Heat detected by hand using hand Heat detected by hand is uncomfortable Heat too high to assess by hand F Noise No unusual noises detected. Slight whine/rattle detected. Moderate whine/rattle detected, easily heard over pump noise. Loud whine/rattle. Disturbingly loud operation/vibrations. A Unplanned Outages RELIABILITY ASSESSMENT Avg No./Year 0 / Year < 2 / Year < 5 / Year < 10 / Year > 10 / Year Summary Efficiency of Level 2 Assessment Flow within Level 5% of duty Flow within 10% of duty Flow within 20% of duty Flow within 40% of duty Flow > 40% of duty B Flow Output point. point. point. point. point. Confirm asset condition rating tables are developed for each asset group; Establish program and resources for Level 2; Undertake more detailed inspections, using qualified staff; Input data to the appropriate software system for the analysis of each asset group; and Undertake a Business Risk Exposure evaluation or criticality assessment to filter assets and identify those assets for Level 3 assessment. Level 3 Condition Assessment Advanced Inspection Program This stage involves the completion of detailed assessments of the assets identified after the completion of the Business Risk Exposure assessment. The tasks in this phase of the study are: Using a risk based condition assessment process, justify a budget for these inspections. Based on the justified budget, identify the best appropriate practice or technique to be used for these inspections identifying:

9 o Technique or procedure; o Number inspections required; o Costs of the inspections; and o Cost benefit. o Cost benefit. For lift stations, examples of these advanced techniques are: Pump Seal and Cut Water Measurements Online Temperature Monitoring Vibration/Modal Analysis Oil Testing and Analysis to determine bearing condition Motor Pulse Tests Summary of Level 3 Assessment Level Review and adopt appropriate condition assessment techniques and technologies for Level 3 assessment. This may require further options evaluation to determine appropriate techniques; Develop costing and preliminary program for all assessments; Review program and costs relative to budget and resources. Revise as necessary; Implement agreed program; Review progress of program and techniques used to ensure appropriate information is being derived; and Input data to the appropriate software system for the analysis of each asset group. Record, Analyze, and Report Findings Assets can be ranked based on the relative risk (Business Risk Exposure) they present to the City and those with the highest risk should be acted upon first. This action may not necessarily be the creation of a CIP project, but may in fact be the increase in maintenance or other actions. A list of standard approaches for high-risk assets is shown below: Status Quo Do Nothing Renew Change Maintenance / Operations levels Upgrade Schedule Regular Condition Assessments monitor Remove Non-Asset Solution (deliver the same level of service another way) All condition data should be tied to an asset within a hierarchical asset register, like Cityworks. It is vitally important that the asset condition data be stored in a framework that allows for analysis of both existing and historical information. Whether the condition assessment goes down to sub-element, component, or item level will determine the level of accuracy and the cost of the assessed condition that is needed. The actual data can reside in several disparate locations, such as a SCADA system, CMMS, GIS, or a financial system, as long as the retrieval of the information is facilitated through the asset register. Frequency of Updating of Condition Assessment Data It is important to understand the appropriate assessment interval for each asset. The assessment interval is the interval between the physical assessments of asset condition. The assessment interval will depend upon where the asset is in its life cycle. Also, the level of detail needed from the assessment will vary based on the existing physical condition and outstanding corrective maintenance work. The following information should be considered in determining assessment interval: Prior maintenance of the asset;

10 Policy requirements for asset condition assessments; The asset's criticality (where the more critical the asset is, the more frequent a physical condition assessment should be conducted); The risk, or consequence of failure, of the asset; The operating context of the asset; Whether the failure mode for that asset is detectable; Special assessments for the City s reporting requirements of asset condition (i.e., regulatory requirements). An assessment approach should be selected that is economically justified, can be carried out in an expeditious manner, allows for the physical attributes of the asset to be assessed, and produces results that are repeatable by multiple assessors. The assessment interval is taken into account when assessing and trending the asset's physical condition over time. The interval needs to ensure that inspections capture any significant changes in asset condition before they can affect asset performance and the delivery of the service. The interval for assessment will vary to suit different assets. Some assets may not warrant any condition assessment program at all because the time between the detection of the predicted failure and the failure itself is too short. The interval for assessment can be altered to suit changes in the asset's profile (for example, the previous condition or age of the asset; its strategic importance, capacity and utilization, and planned service requirements). An initial inspection should be commenced as early as possible in the life of an asset to determine a baseline condition that can be used as a reference point for future comparisons. Whenever maintenance is carried out using work orders, this history needs to update condition records including the date of any rehabilitation work. When preventative maintenance or corrective maintenance occurs, this needs to be integrated with the condition profiles and failure modes registered in the databases. Condition assessments will be updated with each corrective work order. Conclusion In these resource constrained times, asset management is particularly important to ensure that maximum value is extracted from every dollar spent. The tools and techniques learned and used by the leadership allow them to develop a long term view of infrastructure renewal and replacement needs that is based on good information and creates a balance between levels of service, cost, and risk. The City s implementation of advanced asset management helps to ensure that the right projects are completed at the right time and for the right cost.