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a b s t r a c tThe present research investigation deals with the assessment of pollution status in the Indus delta creek system. This manuscript advocates the physicochemical, bacteriological characteristics and heavy metal pollution in the creek system. In the present investigation, the pH, salinity, dissolved oxygen (DO), biochemical oxygen demand (BOD 5 ), chemical oxygen demand (COD), chlorophyll, cyanide, oil and grease, total phosphate, phenol, Kjeldahl nitrogen and total organic carbon (TOC) values were recorded from 36 sampling sites during 6 field surveys conducted in 2011-2013. The creek water samples were also analyzed for their heavy metal contents (As, Cd, Cr, Pb, Ni and Zn). The bacteriological parameters included in the study were total coliform count (TCC), total fecal coliform count (TFC), and total fecal streptococci (TFS). These parameters were determined as per methods described in reference [12]. Salinity of water samples ranged between 15 and 32 ‰ while pH ranged from 7.2 to 7.6. High salinity values indicated the progression of seawater into the creek system. The mean DO was low with a range of 4.2-5.7 mg/L. Low DO concentration was due to high BOD 5 (range 10-78 mg/L) while COD ranged from 320 to 1,334 mg/L. High BOD 5 load is mainly due to organic pollution coming from nearby human settlements. The mean chlorophyll-a content was 0.114 mg/L. Interestingly, higher chlorophyll-a concentration was observed near the mangroves area. The mean cyanide concentration was high, though the source of cyanide could not be traced that needs further study. Oil and grease content of water was also substantial, mainly originated from faulty boats operated in the area. Excessive concentration of oil and grease could be deleterious to marine life forms. The concentration of phosphate ranged between 2.1 and 4.6 mg/L mainly attributed to the agriculture runoff. Phenol concentration was not high (0.01-0.08 mg/L) and, therefore, could not be responsible for adverse environmental implications. The mean concentrations of total Kjeldahl nitrogen and TOC were 59.27 and 4.97 mg/L, respectively. The concentrations of heavy metals in the samples were found to be in the order Zn > Ni > Pb > As > Cr > Cd. The bacterial load was exceptionally higher in all the samples in terms of organisms of public health importance that is mainly attributed to domestic wastewater originated from nearby squatter settlements. In essence, the present study disclosed that the creeks of Indus delta are likely to be polluted mainly because of anthropogenic sources. The continuous accumulation of pollutants in the creek area may have severe ecological and health implications.

a b s t r a c tWater quality of rivers, natural lakes, and reservoirs in Pakistan is being degraded rapidly because of indiscriminate disposal of liquid and solid waste. Water quality of Hanna Lake; Balochistan province in Pakistan has been investigated during 2014. A total of 22 samples were collected during summer and winter months. The physicochemical parameters, metals and bacteriological analysis were performed and compared with WHO, guidelines 2011 and NSDWQ (National Standard of Drinking Water Quality, Pakistan). pH, chloride, hardness, nitrate, total dissolved solids (TDS), Na, K, and Zn are well within the permissible limit as per World Health Organization (WHO) guidelines and NSDWQ. The concentration of sulphate, Ni and Pb were relatively higher with respect to WHO guidelines and NSDWQ. As concentration was within the limit as per NSDWQ while it is relatively higher (0.04 mg/l) as per WHO guidelines of (0.01 mg/l). All bacteriological parameters (total coliform, total fecal coliforms and total faecal streptococci) were extremely high from public health stand point that renders the water unfit for human consumption. The continued deteriorating environmental conditions of Hanna lake reflect ignorance from government side that can be mended by consistent supervision, long term management and strict enforcement of environmental laws pertaining to the protection of environmental resources. The present study recommends that priority should be given to monitor the water quality of Hanna lake on long term basis which would be helpful in future planning and management of this important water resource in already water scarce area.

Increase in road Traffic Accidents is a global phenomenon and Pakistan is no exception. In Karachi, this problem becomes severe due to rapid growth of population. This menace is ruining the lives of thousands of people and making Karachi a worrisome place to live. Recent road geometrical transitions in the city with insufficient accessories have been reducing the problem of traffic congestion to a limited extent. On the contrary, this has erupted as a problem of Road Traffic Accidents which is reaching out of proportions. Recently, induction of a unique feature named, Signal Free Corridor in Karachi has cost many precious lives. In this paper GIS based analysis has been employed by using buffer technique to document the number of Road Traffic Accidents on four Signal Free Corridors, evaluated for five different years. It was revealed that the minor injury accidents were highest in all four Signal Free Corridors. However, in some cases number of severe and fatal road accident cases showed the emerging trend as well. Four types of road users were identified on these corridors out of which riders/pillion and pedestrians were the most vulnerable to Road Traffic Accidents. There is an emergent need to enforce the vehicle speed rules and regulations that would provide breathing time to traffic as well as reduce the incidents of consistent traffic blockages and rising Road Traffic Accidents.

Karachi city is a coastal city near the Arabian sea. Due to its location, wind speed may provide a sustainable small scale wind energy system as well as reduction in power shortage in the city. In this study, wind speed data of Karachi Airport station at 10m height is used to estimate wind speed in the surrounding area with reference to measured wind speed data of the station. This estimated wind speed will then be helpful to assess small scale wind power generation at the unsampled locations. Geo-Statics tool in ArcGIS version 10.1 software was utilised to estimate measured wind speed using different interpolation methods. Descriptive statistics were used to analyse and compare measured and estimated wind speed. The analysis summarises the effectiveness of the estimated wind speed. Time series variations of the wind speed data was also analysed. Temporal mapping showing seasonal variations of the wind speed. The descriptive statistics illustrated a high value of correlation coefficient ‘r’, coefficient of determination R2 which is 99.8% for Ordinary and Universal kriging interpolation methods, while it was calculated 99.6% for Simple kriging. A slightly higher coefficient of variation resulted in Ordinary and Universal kriging methods than the Simple kriging method. The results indicated that all three kriging methods performed better and are more effective to estimate wind speed and wind power in the surrounding area and for Temporal display.