Investing in Sustainable cities. Water Management in urban areas: Yangon s case

Transcription

1 Investing in Sustainable cities Water Management in urban areas: Yangon s case

2 I. Water management: general perspective The main goals of urban water and waste water management are : provide clean water to inhabitants remove wastewater from users to prevent unhygienic conditions remove storm water to avoid damage from flooding (monsoon) 2 Difficulties in developing countries lack of waste management absence of urban planning = obstacle to urban drainage sewer systems inadequate in coverage and in performance lack of awareness

3 3 1.1 Waste water management Waste water Sewage water: water with different wastes: human wastes (feaces, urine), washing water, commercial water etc. Health issues: presence of pathogens for human Environmental issues : pharmaceutical and hormones, probable toxicity of natural products Sewage waters need to be collected and should not be released into the environment (rivers, sea, farming) Solutions House and stores must be connected through pipes to a sewage treatment plant. Controls are necessary to improve the rate of connexion in developing cities. Without connexions : septic tanks, drain field or one site treatment unit

4 1.2 Storm water management Origin From precipitation events In urban area, absence of infiltration Can lead to flooding and water pollution Storm waters need to be collected, evacuated and retreated 4 Case study : Porto Alegre (Brazil) First Brazilian city to develop an Urban Drainage Master Plan, but problems : Bad record and data of the existing network Uncontrolled urban expansion Water quality issues because of illegal connections of sewage into drainage Big amount of sediments, litter and debris Water storm management Detention basins to remove water from inundated area Law to regulate and impose construction of compensatory devices Urban planning restrictions and more controls Good integration between administrative services

5 1.3 Good examples around the world Tokyo (Japan) has one of the most efficient water systems in the world. Its method of detecting and repairing leaks has halved the amount of water wasted by the City in the past ten years from 150 million m3 water to 68 million m3 water. Its' focus on same-day-repair work - has helped to drastically reduce the leakage rate - from 20% in 1956 to 3.6% in 2006, as well as reduce carbon dioxide emissions by about 73,000 t CO2 annually In Chennai (India), urban groundwater recharging raised the city s groundwater levels by four meters between 1988 and 2002 (Sakthivadivel 2007) Water management strategy from Copenhagen (Denmark) municipality has resulted in a reduction in water consumption of 26 percent. This constitutes to savings of $84 million annually

6 II. JICA s vision for Yangon: Assessment and propositions

7 Covered area: The JICA s Masterplan concerns Greater Yangon (Yangon City and 6 peripheric townships) Legal Status: Since 1990, when The State Law and Order Restoration Council (SLORC) enacted the Yangon City Development Act, Yangon City Development Committee (YCDC) is in charge of management and maintenance of all municipal water works and prevent water pollution.

8 II. 1)Yangon situation A) WATER SUPPLY Main figures for Yangon water supply:

9 II. 1)Yangon situation A) WATER SUPPLY Main challenges (1/2): 1) Capacity of YCDC: The Water Supply and Sanitation Department of YCDC has a certain level of capability for implementing the project because they have been operating water supply and sewerage systems for over 100 years. However, modernization of the water supply and sewerage systems has been delayed due to the long economic sanction to Myanmar. 2) Low Service Coverage: Present service coverage by the water supply system of YCDC is only approximately 50%. Moreover, the water demand has been rapidly increasing due to urbanization and population growth of Yangon City. 3) High Water Wastage: Non-revenue Water (NRW) rate in Yangon City is very high (approximately 50%). 4) Unsuitable Water Quality to Drink: The ratio of chlorinated water volume over supplied water volume is only 25%. Actually, it is reported that bacteria was detected from all tap water samples. 5) Aged Facilities: All pump stations in reservoirs and main transmission pipes have already aged and beyond its life span.

10 II. 1)Yangon situation A) WATER SUPPLY Main challenges (2/2): 6) Low Water Tariff: Compared with other countries, the water tariff of YCDC for domestic users is too cheap. Therefore, user awareness on water savings is low. Also, this water tariff level could not cover the investment cost of the construction of facilities: 7) Improper Distribution System:. The total volume of existing distribution reservoirs are approximately three hours of daily supply. This volume is small from a standpoint of appropriate design. There are no distribution blocks despite the large service area. There is no flow meter to grasp actual distribution volume. Also, water meter coverage is approximately 70%. Therefore, it is difficult to estimate the actual water balance.

11 II. 1)Yangon situation B) SEWERAGE AND DRAINAGE Sewerage: The collection system of the current sewerage system was developed in 1888 with its sewerage area being expanded in Then, its wastewater treatment plant (WWTP) was completed in January Collected wastewater have been previously disposed to the Yangon River until December 2004 Drainage: Stormwater in Greater Yangon flows into six rivers/canals, namely; Yangon River, Bago River, Hlaing River, Nga Moeyeik Creek (Pazundaung River), Pan Hlaing River and Twante Canal. The six rivers flow through 47 drainage channels. The Department of Roads and Bridges, YCDC is in charge of maintenance/improvement works of drainage channels within Yangon City. Other streams are being handled by the DDA of Yangon regional government. Although habitual flood occurs in some areas, the people do not seem to consider this as a problem because flood usually disappears a few hours later. Also, flood depth is normally less than a knee in height. Reflecting in the given situation above, the priority for drainage improvement seems very low.

12 II. 1)Yangon situation B) SEWERAGE AND DRAINAGE Challenges: 1) Low Service Coverage: Service coverage in the existing sewerage system is merely less than 10% and the existing water streams passing through densely populated areas are heavily polluted. 2) Inadequate On-site Disposal System: On-site disposal system using pour flush type toilets without septic tank is still widely used in Yangon City. Moreover, no exclusive sludge treatment plant exists in Yangon City. Removed sludge from septic tanks are disposed to the existing WWTP. Such disposal may result to problems in the operation of the WWTP. 3) Institutional Weakness on Drainage Works: The Department of Roads and Bridges of YCDC is responsible for the drainage works in Yangon City. However, the number of staff specialized for drainage works is very limited and the maintenance and improvement works of existing drainage channels is often delayed. 4) Collection System: The existing sewerage collection system was constructed about 120 years ago

13 II. 2) JICA s propositions A) FIGURES Yangon population will grow

14 II. 2) JICA s propositions A) FIGURES And consume more water

15 II. 2) JICA s propositions B) WATER SUPPLY: PRELIMINARY DEVELOPMENT PLAN Development Goals: all citizens in Greater Yangon shall have access to potable water anywhere, 24-hours a day and seven days a week, gradually, by ) Development of Water Resources and Build-up of WTP Capacity Utilization of cheaper water resources from existing reservoirs and transfer of water using river sources. Construction of new Water Treatment Plants using surface water resources such as reservoirs and rivers. Establishment of the system using water resources from both reservoirs and rivers effectively. 2) Establishment of Effective Transmission and Distribution System Build-up of capacity of transmission and distribution as the result of water improvement Control of water volume by establishing stratified transmission and distribution system Introduction of the SCADA system and putting it into practice for water transmission and water distribution Enhancement of the technology of operation and maintenance of pipeline facilities

16 II. 2) JICA s propositions B) WATER SUPPLY: PRELIMINARY DEVELOPMENT PLAN Development Goals: all citizens in Greater Yangon shall have access to potable water anywhere, 24-hours a day and seven days a week, gradually, by ) Reduction of NRW (Non Revenue Water) and Improvement of Billing and Collecting System Replacement/rehabilitation of old distribution pipes in order to reduce water leakage Reduction of NRW as a result of putting the DMA method (Dynamic mechanical analysis) into practice Charging of appropriate water tariff to customers after installation of 100% water meter. Water meters must be maintained well by YCDC. Capacity buildup regarding billing and collecting water tariff and increase service revenue as a result of improvement Connection of service pipes to customers using proper fixing techniques. 4) Capacity Buildup of Water Quality Management Implementation of the water quality management plan Improvement of existing water treatment process and extension of facilities in order to get quality treated water Capacity buildup of operation and maintenance of WTPs

17 II. 2) JICA s propositions C) SEWERAGE AND DRAINAGE: PRELIMINARY DEVELOPMENT PLAN Development Goals: The development goal is for all citizens living in the Greater Yangon to enjoy a safe and healthy life with access to a sewerage system. However, the development must progress gradually. The target year of this development plan is ) Preliminary Development Plan in CBD (Central Business District) 1) Effective utilization of the existing infrastructure and smooth transfer to the new sewerage collection system. The existing sewerage collection system which uses compressors and ejectors should be replaced as its useful life has already expired. Basic gravity flow system will be applied for collecting sewage. 2) A safe city/town without flood damage 3) Creation of a clean water environment as the result of the collection of gray water into the sewerage system. 2) Preliminary Plan in the Existing Downtown Reduction of pollution load caused by gray water due to the installation of appropriate sewerage system and improved sanitation. Creation of a good aquatic environment as the result of improved water quality of drainages, rivers and lakes. Sewage is collected by a separate system without rain water in order to conserve the water environment. Prevention of flood damage as a result of the improvement of drainage system.

18 II. 2) JICA s propositions C) SEWERAGE AND DRAINAGE: PRELIMINARY DEVELOPMENT PLAN Development Goals: The development goal is for all citizens living in the Greater Yangon to enjoy a safe and healthy life with access to a sewerage system. However, the development must progress gradually. The target year of this development plan is ) Response to New Urban Development 1) Preparation of plans for wastewater treatment and drainage system in order to meet the plans for new urban development 2) Reduction of the pollution load caused by human waste and gray water by installing individual treatment plants on site. The wastewater from suburban town areas that are out of the sewerage area should be treated by community plants or individual treatment facilities. It is better to regulate the treatment of wastewater under a new law. 3) Prevention of flood damage by installing appropriate drainage and rain water runoff control facilities 4) Preliminary Plan in the Existing Downtown Preparation of sewerage and drainage treatment plans which meet the development plans and proper implementation of these plans. Formulation of the basic strategy for treating industrial wastewater and development/ implementation of a legal system regarding this issue. Industrial wastewater should be treated using the private company s own treatment plant. It is best that this situation be regulated under a new law. Prevention of flood damage by installing appropriate drainage and rain runoff control facilities

19 III. Ideas for sustainability Integrated Water Resource Management (IWRM): avoiding silo approach for water supply, sanitation and irrigation Payment for ecosystem services: Companies and household must pay a fair price for access to water // Prices should be lowered for poor people (so higher for others) in order to allow 100% access to fresh water Harvesting rainwater and organizing grey water reuse in buildings

20 Thank you!