Fresh water management in south western coastal bangladesh: quality and livelihood strategies

Abstract

Bangladesh faces fresh water crisis in its coastal districts for several reasons such as, salinity intrusion, arsenic contamination, groundwater depletion, floods, cyclones and different types of industrial, agricultural and household pollution. Water crisis increases due to the changing pattem and seasonal variation of rainfall, sea level rising, acceleration of water quality and unavailability of fresh water in the coastal areas. Furthermore, salinity intrusion in groundwater and chemical pollution in surface water play a significant role for creating a severe fresh water crisis. In addition, trace metals introduced into water and consumption of untreated contaminated water create carcinogenic and non-carcinogenic risk to human health. The objectives are to find out the existing quality of surface or groundwater in the coastal area by formulating different indices; assess water, sanitation and hygiene security; measure the livelihood assessment index (LAI) through the weighted average index (WAI) of five livelihood capitals (human, natural, physical, social and financial); coping and adaptation strategies with changing water quality over time and adopted livelihood strategies for the survival of coastal people. Three villages from three adjacent coastal districts (Bagerhat, Khulna and Satkhira) are purposively selected to achieve the objectives of the study. Rajoir (Bagerhat), Gangarampur (Khulna) and Ganapatipur (Satkhira) villages are named as shoreline, interim and inland based on the distance from the coast. Total 67 water samples are collected from five sources, i.e., tube well (TW), pond sand filter (PSF), potable jar (PJ), protected pond (PP) and canal/agricultural field to measure 18 physicochemical and trace metals to produce four indices (water quality index (WQI), heavy metal pollution index (HPI), heavy metal evaluation index (HEI) and hazard index (HI)) which determine the degree of water quality and human health risk. All the samples are tested with appropriate methods in the Water Laboratory of Institute of Environmental Sciences and Central Science Laboratory of the University of Rajshahi, Bangladesh. Bangladesh standard guideline (ECR, 1997) is followed as the permissible limit for all the selected parameters. In addition, 338 household heads (proportionately distributed) out of 2789 are selected using simple random samplings procedure to perform the self-administered and semi-structured questionnaire to know fresh water availability, sanitation-hygiene security, livelihood capitals, coping and adaptation strategies as well as livelihood strategies. Furthermore, 3 FGDs, 16 KIIs and 3 DPHE officials are also surveyed with predetermined checklists to triangulate the laboratory and field data. SPSS, MS excel and Arc GIS software are used for data analysis, map production and spatial distribution. The study reveals that mean WQI, HPI and HI of TW water is increased from shoreline to inland but HEI is reduced from shoreline to inland area. The quality of PP water reports the almost same trend as TW. Mean WQI of PSF water is categorized as 'good' for shoreline and inland but 'excellent' in interim area and the trend shows reducing from shoreline to inland. WQI claims that 100% PP water samples from inland are unsuitable for consumption whereas 25% samples from shoreline areas are in the 'excellent category. WQI and HPI of PJ water claim the reducing trend from shoreline to inland area. In addition, the study results show the pattern of human and natural; physical, social and financial capital indices are changed as of shoreline interim inland, inland interim shoreline, interim inland shoreline, interim shoreline-inland respectively. Human capital indicators education quality (472) and water crisis experience (.647) are higher in shoreline than other two areas. Natural capital indicators fresh water availability (342), fertility of agricultural land (663), water sufficiency (334) and access to open sanctuary (777) are also higher in shoreline areas. The LAI also increases the trend (-323-342-344) and assesses as 'poor' (shoreline) and 'moderate (interim and inland) area. The plastic bottles are dominantly used for preservation of drinking (58.28%) and rainwater (44.08%). Besides, plastic drums, silver pots, earthen and ferro cement materials are also used to preserve water. Mean WAI of preparedness level of household and homestead agriculture is 'moderate' (0.332) in inland and 'poor' in shoreline (0.313) and interim (0.309). Only about 25.15% households are satisfied with the current water supply system. Overall, about 47.34% respondents consume drinking water without treatment and 52.66% respondents use different treatment systems. About 60% respondents of shoreline area use potash alum, followed by boiling (16.30%), filtering (6.52%) for purification of water. Overall, about 10.65% respondents use different filtering processes. Among them 83.33% and 16.67% use commercial filters and sand filters respectively in the shoreline village. Consuming untreated water may be responsible for different water borne diseases. Individually, about 65.76% respondents use PSF technology from shoreline, followed by 16.90% (interim) and 37.35% (inland area). Other adaptation strategies (rainwater harvesting, pond water conservation, PJ water use, re-excavation of pond, boiling pond/canal water) are adopted by households and institutions with seasonal variations. The respondents receive different livelihood strategies, like, changing occupation over time, changing agricultural pattern, rainwater harvesting and use of surface water. Therefore, livelihood is connected with respondent's occupation, income, investment, shifting agricultural, etc. Lastly, intensive care and frequent checkup of water quality along with cooperation and coordination among different local stakeholders will be ensured for reducing fresh water crisis in the study area.