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Tributaries of Lagos lagoon at Oworonsoki and Ebute Meta, known for residential and commercial activities were studied to assess the impact of coastal activities on Lagos lagoon. The mean levels of some parameters at the activity points gave evidences of pollution in the studied areas. The mean values for dissolved oxygen was 2.09 mg/l and chemical oxygen demand was 267 mg/l at Oworonsoki, while at Ebute meta, mean values for same parameters at the activity points were 1.16 mg/l and 786.5 mg/l respectively. The results obtained confirmed that the leachates generated from the activities at the studied locations contributed to the levels of some of the water quality parameters in Lagos lagoon.

River Ona, a major river in Ibadan, into which industries discharge their effluents, was studied to assess the impact of the industrial discharge. The mean levels for some parameters gave evidence of pollution. The mean values for DO (4.9 ± 0.3 mg/l), COD (54.5 ± 0.5 mg/l), PO 4 3-(0.47 ± 0.09 mg/l), SO 4 2− (20.65 ± 0.85 mg/l) were reported for the upstream region, while the downstream mean values for same parameters gave 3.72 ± 0.37 mg/l, 211.20 ± 59.6 mg/l, 1.06 ± 0.20 mg/l and 23.62 ± 3.20 mg/l, respectively. The effluent was also analysed, and the results obtained confirmed that the effluent was not the only source of pollutants in the river.

Waste to energy (WtE) refers to any treatment process that creates energy in the form of electricity or heat from a waste source. This research reviews the potential uses of municipal solid waste generated at the University of Lagos, Akoka campus as a sustainable energy source for the tertiary institution. Waste characterization study of the residual waste at the University's sorting centre was conducted to determine the amount, composition and physical properties of the waste. A novel compositional trending ratio (CTR) was used to evaluate the possible calorific variation in samples using ASTMD3286-77 method. A validation of the experimental results was carried out using energy estimation model described by Smith and Scott (2005) and World Bank (1999). The major components of the residual waste were mainly polythene materials (24%), inert (30%), organic waste (15%), and paper (15%). The average calorific value of 17.23 MJ/kg and moisture content of 41.3% could potentially generate 34, 787 kWh daily (about 48.32% of the 72,000 kWh energy demand of the University). There was no significant statistical difference between experimental energy estimation of samples and model energy values (p < 0.001) and a Relative Percent Difference (RPD) < 3% (experimental energy 1112.1MJ/Kg, model value 1108.3 MJ/Kg). The major challenge to adopting WtE technology is the gap in daily tonnage of waste generated which can be overcome through collaborative solid waste management program with closed neighborhood and tertiary institution. The findings provide resourceful information on sustainable management of waste generated for a typical tertiary institution.

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