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Finding the optimal solution to address problems in sewer management systems has always challenged asset managers. An understanding of deterioration mechanisms in sewers can help asset managers in developing prediction models for estimating whether or not sewer collapse is likely. The effective use of deterioration prediction models along with the development and use of life cycle cost analysis (LCCA) can contribute to the goals of reducing construction, operation and maintenance costs in sewer systems. When sewer system maintenance/rehabilitation options are viewed as investment alternatives, it is important, and in some cases, imperative, to make decisions based on life cycle costs instead of relying totally on initial construction costs. The objective of this paper is to discuss the application of deterioration modelling and life cycle cost principles in sewer system management, and to explore the role of the Markov chain model in decision making regarding sewer rehabilitation. A test case is used to demonstrate the application of the Markov chain decision model for sewer system management. The analysis includes evaluation of this concept using dynamic programming and the policy improvement algorithm.

Pumped-storage hydroelectricity (PSH) is considered as an effective method to moderate the difference in demand and supply of electricity. This study aims to understanding of the high capacity of energy production, storage and permanent exploitation has been the prominent feature of pumped-storage hydroelectricity.

In this paper, the optimization of energy production and maintenance costs in one of the large Iranian PSH has been discussed. Hence, a mathematical model mixed integer nonlinear programming developed in this area. Minimizing the difference in supply and demand in the energy production network to multiple energies has been exploited to optimal attainment scheme. To evaluate the model, exact solution CPLEX and to solve the proposed programming model, the efficient metaheuristics are utilized by the tuned parameters achieved from the Taguchi approach. Further analysis of the parameters of the problem is conducted to verify the model behavior in various test problems.

The results of this paper have shown that the meta-heuristic algorithm has been done in a suitable time, despite the approximation of the optimal answer, and the consequences of research indicate that the model proposed in the studied power plant is applicable.

In pumped-storage hydroelectricity plants, one of the main challenges in energy production issues is the development of production, maintenance and repair scheduling concepts that improves plant efficiency. To evaluate the mathematical model presented, exact solution CPLEX and to solve the proposed bi-objective mixed-integer linear programming model, set of efficient metaheuristics are used. Therefore, according to the level of optimization performed in the case study, it has caused the improvement of planning by 7%–12% and effective optimization processes.

The purpose of this paper is to communicate and share experiences with other dam designers, operators and maintenance officers arising from the rehabilitation of the Osborne Dam outlets, pursuant to informing future dam outlet designs and rehabilitation of similar dam outlets.

This paper documents and utilizes actual events that occurred before and during the rehabilitation of the outlets. Some solutions applied were unique, with resultant innovative engineering designs being decided on site. Realizing that a descriptive research format would best serve the sharing of experiences of the outlets’ rehabilitation, the case study approach was selected. Before commencement of the rehabilitation works, the different operational problems that had been identified, photographed and documented by the dam’s operating staff were verified by the dam owner’s engineers, technicians and consultants. Visual and photographic verification was done using divers for areas under water. Literature review was conducted so as to learn from solutions employed elsewhere. A physical model of the solution considered the best way to keep the intake tower dry was made and tested.

The outlets’ rehabilitation works, taking 12 months to complete at a total cost of US$5 million, involved installation of new service gates, replacement of the sleeve valves, refurbishment of the butterfly valves and provision of dewatering pumps.

This paper offers unique experiences and lessons for dam designers and other dam operation and maintenance officers while contributing to the body of knowledge of outlet works rehabilitation.

This paper seeks to define a theoretical model for the urban regeneration of mass housing areas based on citizen initiative, self-management and self-financing in the form of the neighbourhood cooperative. This paper aims to identify mechanisms for economic resource generation that enable the improvement of the urban surroundings and its buildings without assuming disproportionate economic burdens by the local residents based on two principles, the economies of scale and service provision.

The research is structured in three phases: a literature review of the different trends in self-financing for urban regeneration and the conceptual framework for the definition of a cooperative model; the definition of theoretical model by analysing community ecosystem, neighbourhood-based services and the requirements for its economic equilibrium; and the discussion of the results and the conclusions.

The results show the potential of the cooperative model to generate a social economy capable of reducing costs and producing additional resources to finance the rehabilitation process. The findings show not only the extent of economic advantages but also multiple social, physical and environmental benefits. Its implementation involves the participation of multiple actors, which is one of its significant advantages.

The main contribution is to approach comprehensive urban rehabilitation from a collaborative understanding, overcoming the main financing difficulties of the current practices based on public subsidy policies. The model also allows an ethical relationship to be built with supplier companies by means of corporate social responsibility.

Develops actuarial benefit‐cost ratio models of rehabilitation and new dwelling construction to indicate when investment in public housing is best diverted from new construction into rehabilitation of existing dwellings. The data used by the models are based on an empirical study of the mortality of New Zealand housing stock and assumed schedules of no depreciation, straight line depreciation, and diminishing value depreciation of dwelling services. Shows that under conditions of no depreciation it would be impossible to rehabilitate dwellings fully within a justifiable budget at market discount rates. The benefitcost ratios are also overly sensitive to fluctuations in the mortality of the housing stock. Under the more realistic conditions of straight line and diminishing value depreciation, the benefit‐cost ratios are insensitive to fluctuations in mortality and decision making whether to invest in rehabilitation or new construction is viable.

Infrastructure maintenance management has become a challenge field for civil engineers and government managers because of the increasing number of deteriorated structures, their complicated spatial locations, the improved service requirements, the limited maintenance budgets and so on. Therefore, maintenance management approaches have been developed for civil infrastructures such as bridges and roads over the past several decades, but most of such approaches focused on one specific structure only – project‐level maintenance management. Now, there are increasing demands and appropriate conditions for network‐level maintenance management for civil infrastructure systems. Aims to explore such a maintenance management approach by integrating and applying the current information technologies, which include the database management system, geographic information system, genetic algorithm and the Internet. Several possible applications of each technology are discussed for solving real‐world problems.

The purpose of this paper is to present a conceptual risk assessment technique to aid facility managers with developing robust asset management programs. It proposes to evaluate three discrete risk sensitivity levels relative to the recognition of stochastic costs on expected budgetary outcomes. The paper expands the domain of available risk assessment techniques toward estimating impacts from uncertainty on desired levels of service.

The paper explores the concept that facility managers can cost‐effectively manage robust asset management programs. This is accomplished by evaluating simple relationships between risk‐sensitive decision‐response alternatives and systems degradation characteristics. The resulting parameters are aggregated to estimate expected budgetary outcomes for robust asset management programs.

The paper reveals that if facility managers assume risk‐avoidance positions, they can positively affect expected budgetary outcomes for robust asset management programs. Facility managers can manage the magnitude of these adverse impacts by mitigating stochastic costs associated with the completion of unscheduled asset management activities.

The expected implications are enhancements to the abilities of facility managers to cost‐effectively manage stochastic costs relative to risk sensitivity and desired levels of service. However, because of the chosen research approach, the research results may lack general usability. Therefore, researchers are encouraged to test the proposed propositions further.

The practical implications allow facility managers to cost‐effectively manage adverse impacts on expected budgetary outcomes for robust asset management programs.

The expected contribution is a tool for facility managers to manage uncertainty when allocating limited financial resources among the competing corrective, maintenance, and rehabilitation activities within robust asset management programs.

The paper fulfills an identified need to study how facility managers can do more with less. This need to be cost‐effective requires facility managers to recognize stochastic costs on the expected budgetary outcomes for robust asset management programs.

The purpose of this paper is to investigate the key productivity constraints faced by New Zealand (NZ) road pavement maintenance and rehabilitation contractors (RPMRCs) and the associated mitigation measures.

Interview-based exploratory research strategy was used to survey senior managers and directors of medium- to large-sized road contracting firms in NZ. Empirical data were analyzed using the multi-attribute analytical technique.

Results revealed 70 productivity constraints faced by the RPMRCs in NZ; in diminishing order of influence, these constraints were aggregated into eight broad categories as follows: finance, workforce, technology/process, statutory/regulatory compliance, project characteristics, project management/project team characteristics, unforeseen circumstances and other/external factors. The most important constraints in each of the eight broad categories were presented.

The key limitation of the research is that it was based on feedback from a limited number of participants which were less than the minimum required to represent the views of the potential participants in the sampling frame for the study. As a result, the findings may not be reliably generalized beyond the scope of the data used. Further research on the subject is recommended to ensure that the representation of the views of the individuals and companies that comprised the sampling frame is achieved. The current findings could be formulated as propositions or hypotheses to be tested in future confirmatory research.

At the industry level, the findings could provide the basis for the skill development programs of the NZ RPMRCs. The application of the research findings by the RPMRCs and consultants could result in significant improvement in the productivity of the NZ roading sector and the sector’s enhanced contribution to the economy.

Currently, there is little research on the priority constraints to productivity and performance in the NZ roading sector. The findings contribute to knowledge by revealing critical factors constraining productivity performance of the NZ RMRCs and the associated improvement measures. New and more enriching viewpoints were provided on how contractors could leverage their limited resources to address the identified key constraints.

Several rehabilitation planning methods are reported in the literature for public infrastructures, such as bridges, pavements, sewers, etc. These methods, however, are limited to specific types of infrastructures. The purpose of the present research is to develop a novel and generic method for Maintenance and Rehabilitation Planning for Public Infrastructure (M&RPPI), which aims at determining the optimal rehabilitation profile over a desired analysis period.

The M&RPPI method is based on life‐cycle costing (LCC) with probabilistic and continuous rating approach for condition states. The M&RPPI uses a new approach of “dynamic” Markov chain to represent the deterioration mechanism of an infrastructure and the impact of rehabilitation interventions on such infrastructure. It also uses genetic algorithm (GA) in conjunction with Markov chains in order to find the optimal rehabilitation profile. A case study is presented with a comparison between the traditional Markov decision process (MDP) and the newly developed method.

The new method, which generates lower LCC, is found practical in providing a complete M&R plan over a required study period, compared to a stationary decision policy with the traditional MDP. In addition, GA is found useful in the optimization process and overcomes the computational difficulties for large combinatorial problems.

The implementation of the developed models is limited to only four alternatives/actions. However, the developed models and framework are superior for MDP.

The developed methodology and model play essential roles in the decision‐making process.

The new method is beneficial to researchers and practitioners. It is developed for a single facility; however, it provides a major step towards a broader infrastructure management system and capital budgeting problems.