Guwahati

Organizer: PFI Foundation

Venue: Guwahati, Assam

The study deals with the detection of trace elements – Cu, Co, Cd, Zn, Fe, Mn, Ni and Pb along with pH and ORP in the groundwater of Guwahati and its adjacent areas. Toxicity of a metal depends on its concentration, which adversely affects any biological activity. Almost all the metals are toxic at higher concentrations, few in low concentrations and few others even in trace like As, Pb, Hg, Cd etc. The presence of such metals in groundwater is a subject of concern. Groundwater that contains higher amount of metals affects public health to a great extent when it is used for drinking and domestic purposes.

In this study, groundwater quality monitoring and evaluation of Greater Guwahati is presented based on the physico-chemical characteristics of thirty samples collected on grid pattern. The various parameters analyzed include pH, electrical conductivity, temperature, Dissolved Oxygen (DO), Total Dissolved Solids (TDS), alkalinity, hardness, Na⁺, K⁺, CA⁺⁺, Mg⁺⁺, NO₃^-, SO4^--, Cl^- and F^-. The results were compared with water quality standards prescribed by BIS and WHO.

The study presents a preliminary hydrological investigation of the Deepar Beel, a natural freshwater lake near Guwahati, and notes the theoretical aspects of the techniques to be used, methodologies and instruments for conducting a detailed study of the natural processes at hand.

Deepar Beel acts as a natural stormwater reservoir during monsoon period and is greatly influenced by the rapid urbanization and improper land use pattern of Guwahati. It receives a large portion of sewage of the city, but the preliminary investigations reveal that the Beel is largely free from significant levels of pollution. This is due to the dilution effects of large storm water runoff during monsoons as also the release of the Beel water to river Brahmaputra through the Khanajun outlet. Yet, the soil quality is found to have deteriorated to a large extent.

Various parameters of soil and water quality indicate that the process of eutrophication is in progress in this wetland. Although many trace elements are present in the Beel sediments, no known toxic effects are observed on aquatic life. Increasing sedimentation and reduction in lake water capacity and inflow are also observed.

The study on groundwater quality of Greater Guwahati analyses various trace elements in samples and ascertains that their concentration is much higher than the tolerance limit prescribed for drinking water. The trace element analysis focuses on metals such as Cu, Co, Cd, Fe, Zn and Pb.

Owing to the inadequacies of piped water supply, the Greater Guwahati area depends on groundwater from ringwells and tubewells for drinking purposes. Groundwater is mostly polluted from the effluents discharged by industries on land, seepage from sewage lines & tanks and application of pesticides on agricultural land. Due to the low flow velocity, groundwater once contaminated will remain so for longer periods. Metals assume significance because of their greater toxicity, accumulative and non-biodegradable behavior. 

In the recent past, Dr. Dipul Choudhury from Guwahati (Assam), managed to ensure rainwater harvesting arrangements in his newly constructed multistoried building at Tarun Nagar, Guwahati (Assam).

Currently the college has a daily water consumption of 17.8KL and inadequate supply. The design integrates water conserving devices such as waterless urinals and eco-san toilets with grey and black water treatment systems and rainwater harvesting.