The cheapest quotation for the pumping solution may look attractive for the contractor………but not the client. There are many types of pumping stations and each have their benefits and all have varying lifecosts. It is important that you get the right pumping station for the right job – every time.
When carrying out an assessment of different alternatives for a new pumping station, the whole-life costs for the different solutions should be evaluated and compared. This is usually done by means of a net present value analysis.
For example, a new pumping station for a small development could have either a submersible pumping station with a 100mm pumping main to the nearest sewerage system, or an above-sewage pumping station with a progressive cavity macerating pump and a small bore polyethylene pumping main. The latter is likely to have reduced capital costs, particularly in respect to the pumping main, which will be relatively cheap to install. However, the higher velocities in the pumping main and the resulting higher pumping head may increase operating costs, even allowing for greater efficiency of positive displacement pumps compared with centrifugals. Thus a net present value analysis will enable the most cost effective solution to be determined. A further option is to consider the use of submersible pumps with proprietary cutters or grinders.
There is a tendency among the various water utility companies to use different asset lives for M&E plant eg. 10, 15 or 20 years. In some cases, the life of the plant may be based on the total number of operating hours rather than a fixed period. These variations can have a significant effect on the calculated net present values and their relative importance in the estimation of whole-life costs.
Consult with professionals to ensure the proposed solution for your project is built to last.