pre-determined weighted attributes. The weighted attribute methodology is designed to provide the best possible overall outcome and may consider such matters as health and safety, value for money, productivity, certainty of outcome, previous experience, innovation and risk. Occasionally lowest price conforming method is used. It is usual for specific contracts to be prepared for every tender. Each one is up-dated to include the latest standards, materials and techniques. A specialist contract lawyer is employed to check and review larger contracts prior to tendering. Construction - the construction phase is normally managed by Council project engineers supported by specialist consultant project managers and supervisors. A risk register is compiled at the beginning of each project and is monitored throughout the construction to help ensure smooth progression and successful outcome. Significant variations in the final design may have to be returned the Asset and Services Committee for verification and approval. The capital works programme is led and planned by the Planning and Development Engineer. The main drivers of the capital programme are categorised between growth, levels of service improvement and renewal and the costs apportioned to each category. Capital Investment Strategy A number of techniques have been developed to identify and prioritise the demands for new and upgraded infrastructure. These are discussed in more detail in the chapters relating to growth and levels of service. Dynamic mathematical models have been developed to provide detailed and accurate predictions of flow and pressures throughout the Blenheim and Picton reticulations. The models are built to represent the individual characteristics of each of the distribution systems and can be adjusted to represent specific demand patterns or system configuration. The outputs of the models are compared with actual experience of flow and pressure tests from the field so the models can be calibrated and verified. Through the models areas of poor flow or low pressure can be identified and solution options considered. New developments, requests for connection to the system or increases in demand can be added to the model in order to predict the likely effects. The benefit of dynamic models is that multiple combinations of demand parameters can be compiled into different scenarios, the consequences can be quickly determined and possible remedies tested. The models are used both in-house and by specialist design consultants to derive preliminary design solutions. Depending on the size and costs of the project the design options may be peer reviewed. The models are constantly under review and development. They were recently used to determine the number, size and configuration of distribution pumps at the Central Water Treatment Plant in order to meet current and future demand at optimal efficiency within the constraints of the site. The models are also used to determine the expected flow and pressure within the system to meet the firefighting code of practice. Construction costs are one of the criteria to be considered when evaluating major investment projects. The whole life costs of the new infrastructural assets as well as the cultural, social and environmental implications must be considered. Tools and techniques such as Cost/Benefit Analysis, Assessment of Environmental Effects and cultural impact assessments have been employed on recent major projects and will continue to be used. Council uses a variety of methods of communication with communities that may be affected by proposed capital works including: the annual plan process, long term community plan (LTP) process, consultative working groups for specific larger projects, meetings with residents’ associations, distribution of pamphlets to households and information on Council’s web site. Page 69