The effects of the implementation of grey water reuse systems on construction cost and project schedule

One of the factors emphasized by Leadership in Energy and Environmental Design (LEED), a national consensus-based standard under the United States Green Building Council (USGBC) for developing sustainable or high performance buildings, is water efficiency. A LEED registered project can attain up to five points under water efficiency upon successful integration of various techniques to conserve water. Many techniques are available to conserve water and grey water reuse is one option considered by many LEED registered projects. In spite of widespread popularity, some of the sustainable techniques including grey water reuse, which is recommended by the USGBC and various agencies engaged in green building constructions, are not viable in many parts of the United States due to their effects on construction cost and project schedules. Even though a project could get one or multiple points upon successful implementation of a grey water reuse system and conserving potable water, the following factors may have a positive or negative effect on the design team?s decision to implement a grey water reuse system: capital cost, maintenance cost, LEED credits, local plumbing codes, project schedule, local water conservation issues, complexity of the system, etc. Implementation of a grey water reuse system has a significant effect on the capital cost of a project. The increase in cost may be attributed to dual sanitary and grey water distribution piping which doubles construction piping costs. Disinfection treatment, filtration, overflow protection, grey water storage tanks, etc. also add to the cost of construction. Ninety percent of the projects claim that project schedule is not affected by the implementation of a grey water reuse system in a green building project. The factors which prevent the project team from implementing a grey water reuse system include capital cost, maintenance cost, local plumbing codes, local water conservation issues, complexity of the system, etc. LEED credits and the spirit of sustainability are the factors which have a positive effect on the design team?s decision to implement a grey water reuse system.