Abstract:
Sewer reticulation system refers to a network of sewer pipes, manholes, sewer pump stations and sewerage treatment plants. Many developing countries share a common challenge concerning sewer system and that is extension of the sewer network. Most of them tends to use manual method for sewer extension thereby ending up spending more than what was budgeted for. This research is aimed at enhancing sewer reticulations systems in Nyeri Municipality. It is aimed at mapping the existing sewer network within the municipality, mapping all the households that are already connected to the existing sewer network or if not, can be connected, estimate the amount of sewerage the connectable households may produce per day, mapping the households which are located far from the existing sewer network and are unconnectable due to the long distance, mapping the households which might be closer to the existing sewer network but cannot to be connected due to the rugged terrain where sewerage would not flow with gravity and then lastly determine suitable locations for siting pump stations to serve the household whose sewerage would not flow with gravity. The main analysis involved in this research include Proximity analysis, Least Cost Path analysis which was used for extension of sewer network and Suitability analysis which was used for site selection for pump stations. The results showed out of 19410 households only 8844 could be connected to the existing sewer network. 3479 households could not be connected because they were far from the existing sewer network while 7087 households could not get connected due to terrain difficulties. This means that construction of sewer pump stations within the municipality should be emphasized more than sewer extensions. Least cost paths were generated to extend sewer to the 3479 households while suitability analysis was done to site pump stations closer to the 7087 households. The estimated amount of sewer expected to flow from the 8844 households was determined to be 641.2 M3.