Water Quality Status and Challenges. in the SDG Era

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1 Conference on Green Growth Solutions April 26, 2017 Dhaka, Bangladesh Water Quality Status and Challenges in Bangladesh in the SDG Era Tanvir Ahmed, PhD Department of Civil Engineering, BUET Dhaka, Bangladesh Presentation Outline Safe water and MDG targets, progress in national water supply, extent of the problem and impact of climate change Water management challenges in the urban context Challenges to meet the water quality target under the SDG era

2 What is Safe Drinking Water? The Millennium Development Goal 7 (MDG7) Target 10 was to halve by 2015 the proportion of people without sustainable access to safe drinking water and basic sanitation. Improved Drinking Water Sources - Household connection - Public standpipe - Borehole - Protected dug well - Protected spring - Rainwater collection Progress in National Water supply Bangladesh has been able to achieve the coverage three years before the MDG target year of % The success of Bangladesh in the water sector can largely be owed to progress in rural areas.

3 Urban and Rural Disparities Year Total improved Estimated coverage 2014 update Piped onto premises Other improved Other unimproved Surface water % 23% 58% 17% 2% % 25% 57% 16% 2% % 27% 56% 16% 1% % 29% 55% 15% 1% % 31% 54% 15% 0% % 32% 54% 14% 0% Urban (JMP, 2014) Rural Year Total improved Estimated coverage 2014 update Piped onto premises Other improved Other unimproved Surface water % 0% 65% 28% 7% % 0% 69% 25% 6% % 0% 74% 22% 4% % 1% 77% 19% 3% % 1% 82% 16% 1% % 1% 83% 16% 0% Arsenic Contamination Arsenic contamination of ground water has reduced population coverage by safe water in Bangladesh from a staggering 97 per cent to approximately 74 per cent (GoB, 2002). According to MICS , 97.9 percent of household members are using improved sources of drinking water but after adjusting for arsenic contamination the coverage figure is reduced to 85 percent.

4 Arsenic Mitigation Challenges Arsenic contamination is a complex problem and the solutions so far available are high-tech and costly, beyond the affordability of the poor rural people exposed to arsenic contamination. Low-cost options need close monitoring and frequent monitoring of millions of water points is a challenge. Microbial health risk of some of alternate water supply options has been found to be even higher than arsenic health risk. Avoidance or risk substitution is a challenge in rural condition. Problems with Alternate Water Supply Options Microbial Disease Burden negates the advantage of lower arsenic concentration in most water supply options Microbial DALYs, 10^-6/person- Yr LCL Median UCL DW(d) DW(w) DTW(d) DTW(w) PSF(d) PSF(w) RWHS(d) RWHS(w) STW Arsenic Mitagation Options

5 Coastal Salinity: Scarcity of Fresh Drinking Water The shallow aquifers in the coastal areas Pockets of salinity inland, especially in the Comilla and Chandpur districts. coastal zone vulnerability will become more acute in a changing climate from the combined effects of sea level rise (SLR), changes in upstream river discharge, and increased frequency of more intense cyclones Coastal Salinity: impact of Climate Change on Drinking water (World Bank, 2014) Freshwater river area (0 1ppt) is expected to decrease from 40.8 percent at the baseline to 19.7 and 17.1 percent in the best and worst case future scenarios Immediate impact on the supply of drinking water from rivers. (1ppt being the critical level of salinity for drinking water)

6 Sustainable Development Goals At the United Nations Sustainable Development Summit on 25 September 2015, world leaders of 193 countries of UN General Assembly adopted Sustainable Development Goals (SDGs) SDG Target 6.1 by 2030 achieve universal and equitable access to safe and affordable drinking water for all. the existing improved water options, though considered safe at the source, there is a question whether this water remains safe at the consumer level or whether or not equitable access to it is ensured bringing the remaining 13% people under safe water coverage can pose serious challenges

7 Challenges to achieve SDG 6.1 Target Arsenic problems still looms the 20 million people still drinking arsenic contaminated water (UNICEF 2010) need to be brought into the safety net. Fecal contamination a threat to safety of drinking water about 40 percent of all improved water sources in Bangladesh were found to have unsafe levels of E. coli Proximity to water source affects accessibility Of the population covered by improved water sources, about three quarters have on premise access, while the remaining quarter must travel off premise to collect water. Challenges to achieve SDG 6.1 Target Depleted Groundwater table limits accessibility There are about million hand tubewells, many of them become nonoperational during the dry season when groundwater level drops as a result of intensive pumping for dryseason Boro rice cultivation.

8 Challenges to achieve SDG 6.1 Target The remaining 13% population comprises poor populations, slum-dwellers, remote areas, places with geographical complexities, hard-to-reach areas, hilly areas and climate-change prone areas. may require larger investments to overcome such barriers Urban Water Challenges

9 Ever-increasing Demand Overall population growth rate 1.5% Urban population growth rate due to influx is 3.5% Growth rate in metropolitan cities 5% Source: SDP Population in Dhaka city has increased from 6.62 million in 1990 to million in 2014 and is projected to be million in 2050 (UN 2014) Pressure on Groundwater Resources Source: Dhaka Water Supply Master Plan The demand for water in 1963 was 150 MLD. Today the demand is 2500 MLD (IWM, 2010)

10 Inadequate Sanitation and Wastewater Treatment affecting water quality Disproportionate Investment in Water Supply and Sanitation Water Supply network of DWASA Sewerage network of DWASA

11 Disproportionate Investment in Water Supply and Sanitation Water Supply Description Total Coverage (Population) 100 % Production Capacity 2420 MLD Deep Tube Well 702 Nos. Surface Water Treat. Plant 04 Nos. Length of Water Line 3461 Km Registered Consumer 3,50,722 Nos. Sewerage System Description Total Coverage 30 % Sewer Treatment Plant 01 Nos. Sewer Lift Station 28 Nos. Length of Sewer Line 916 Km Registered Consumer 82,390 Nos. Pollution of Surrounding Rivers Pollution of the surrounding rivers limiting their options as a viable drinking water source Source: thedailystar.net Source: World Bank, 2006 Water treatment by conventional technology may fail to produce water to drinking water standard

12 Operational Difficulties in SWTP High levels of Ammonia in the raw water near the intake in the dry season Increased chlorine dosage required (increased operational cost) Potential risk of trihalomethanes. Saidabad WTP intake Source: Alam and Badruzzaman 2012 Large Investments to Convey and Treat water from Distant Sources Source: Dhaka Water Supply Master Plan

13 Service Quality and System loss affects water quality Leakage increase flow rates in pipe network causing unnecessary system losses and supply interruptions in peak hours. Banglades h Leakage results in higher chances of drinking water contamination, Reduces water service quality and consumers willingness to pay Unaccounted for Water WSP (2014) Benchmarking to Improve Urban Water Supply Delivery in Bangladesh. The World Bank

14 Problems with Chlorination Treating water with organic content may generate trihalomethanes after chlorination Asian Water Development Outlook Bangladesh has a very poor national water security score compared to other countries in the world Main reasons: - Poor water infrastructure (piped water coverage) - Poor water quality in rivers and sanitation/wastewater treatment coverage - Poor resilience to water related disasters Bangladesh (ADB, 2016)

15 Other Problems in Urban Context Iron and manganese content of groundwater pose significant challenge to functional water supply operations, particularly of piped systems. Poor tariff Structure discourages major investment Inadequate infrastructure for fecal sludge management SDG Target for Water Supply by 2030 achieve universal and equitable access to safe and affordable drinking water for all. Major barriers in the context of urban water supply - Safety of water at the consumer level - Accessibility of water (groundwater depletion) - Disproportionate investment on sanitation and sewerage infrastructures - Climate change effects (affecting salinity) - Safety of existing water supply infrastructure - Equal access to water (slum populations)

16 Final Words Achieving SDG target for drinking water will require a multi-sectoral approach. Major cities will need to invest in sanitation either by the introduction of sewer systems, or in ensuring efficient and effective collection, handling and disposal or re-use of septic sludge from latrines and septic tanks. Maintain a tariff structure which accommodates a safety net for low income consumers, while progressively charging high volume users Continuous monitoring of essential water quality parameters critical to a specific drinking water supply system Modernize Water infrastructures. Thank you for your kind attention