GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 INTRODUCTION TO WATER SUPPLY AND WASTEWATER MANAGEMENT IN HUE CITY, VIETNAM Pham Khac LIEU*, Nguyen Bac GIANG Department of Environmental Science College of Sciences, Hue University, Vietnam
Contents 1. Hue city at a glance 2. Water sources in Hue 3. Water use and supply in Hue 4. Wastewater management in Hue 5. Threats to water supply and WW management in Hue 6. Remarks GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 2
1. Hue City at a glance Huong Tra Town Phu Vang District Hue city Thua Thien Hue Province Huong Huong Tra Thuy Town Town Administrative division in Vietnam Province/City * ( 都道府県 ) Hue City City/District/Town ( 市 ) Ward/Commune GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 3
1. Hue City at a glance Hue City The Citadel • Area: 71.7 km 2 • Population: 342,500 (2011) • Ancient capital of Vietnam (18 th ~ first-half 20 th centuries) • A World Cultural Heritage (since 1993 by UNESCO) • Famous destination for tourists, a “festival city” of Vietnam The King’s Tomb Source: Hue city’s Statistics Office, 2011 GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 4
1. Hue City at a glance Unused Agriculture 1.8% Residential 22.5% 29.1% Forestry 5.4% Specially Industry & Agro- construction used forestry Land use (2010) 28.5% 41.2% 1.3% Services & tourism (Source: Hue city’s Statistical Yearbook, 70.2% 2010, 2011) Economic activities (2009) GEOSS-AP/AWCI Session, Tokyo, May 27th 2014
1. Hue City at a glance Climate conditions • Tropical monsoon, two seasons (dry: Mar ~ Aug, rainy: Sep ~ Feb) • Annual average temp.: 24-25 ° C (highest: 38-40 ° C) • Annual rainfall: 2,500 mm Source: www.huecity.gov.vn GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 6
1. Hue City at a glance Flood in Hue city • Early flood: May- Jun., main flood: Oct.- Dec. • No. of floods per year: 3-5 (average), 9 (highest) • Flood amplitude: 3-5 m • Flooding duration: 3 – 5 days Hue Citadel’s Gate before and during flooding GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 7
2. Water sources in Hue • Surface water is major source • Plentiful water thanks to high rainfall and extensive network of rivers (Huong river and its branches) • Unequally distributed rainfall over the seasons causes flooding in the wet, and some droughts A dense river network around Hue City in the dry season. GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 8
2. Water sources in Hue Huong river (Perfume river) • catchment area: 2,830 km 2 • 3 tributaries (2 in upper and 1 in lower section) • 4 branches within city’s boundary • irregular flow: 70 -75 % of total flow from Oct.- Dec. Variation in monthly average flow rate of • upstream dams and Huong river’s tributaries (Tinh, 2010) downstream barrage •Average flow: 9,660 m 3 /min •Lowest flow: 1,632 m 3 /min GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 9
2. Water sources in Hue Water quality of Huong River • Generally good for domestic use • Slightly organic, nutrient and pathogenic pollution Water quality of Huong river and branches in 2011 (survey data) DO, COD, BOD 5 , SS, NO 3 -N, NH 4 -N, PO 4 -P, Sample pH mg/L mg/L mg/L mg/L mg/L mg/L mg/L RW1 6.6 7.7 9.7 2.5 14.1 0.3 0.1 0.1 RW2 7.2 7.0 20.5 1.3 23.0 1.0 0.3 0.1 RW3 7.1 6.6 18.0 2.5 18.1 0.8 0.1 0.1 RW4 6.9 5.7 10.5 3.8 12.7 1.8 4.2 0.0 RW5 7.2 5.7 7.6 3.2 10.2 1.2 2.1 0.0 Average 7.0 6.5 13.3 2.6 15.6 1.0 1.3 0.1 A1 6-8.5 6.0 10 4 20 2 0.1 0.1 National regulation * A2 6-8.5 5.0 15 6 30 5 0.2 0.2 *National Technical Regulation for Surface Water Quality (QCVN 08:2008/BTNMT): A1-applied for surface water able to use for domestic supply without treatment. A2-applied for surface water able to use for domestic supply with appropriate treatment GEOSS-AP/AWCI Session, Tokyo, May 27th 2014
2. Water sources in Hue Van Nien Intake Da Vien Intake Van Nien Intake Da Vien Intake 35 0.20 30 0.15 NH4-N (mg-N/L) Turbidity (NTU) 25 20 Nationalstandard value 0.10 15 10 0.05 5 0 0.00 Jan. Feb. Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan. Feb. Mar Apr May Jun Jul Aug Sep Oct Nov Dec Van Nien Intake Da Vien Intake 5000 Total coliforms (MPN/100mL) Water quality of Huong River at 4000 Van Nien Intake and Da Vien Intake in 2011 3000 National standard value (Source: Monitoring data by 2000 HueWACO) 1000 0 Jan.Feb. Mar Apr May Jun Jul Aug Sep Oct Nov Dec GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 11
3. Water use and supply in Hue 3.1. Water use • Public piped water is main use in Hue city • Tap water coverage: 1%2% o 100% area-based since 2010 (HueWACO) o 97% households (Center for Preventive 97% Medicine, 2010) Public piped water Drilled wells Dug wells o 99% population-based Distribution of domestic water use by households in Hue city (Center (HueWACO, 2013) for Preventive Medicine, 2010) HueWACO: Thua Thien Hue Water Supply & Construction State-owned Co.Ltd. GEOSS-AP/AWCI Session, Tokyo, May 27th 2014
3. Water use and supply in Hue Public piped water use Residential Institutional • 76% for residential use Industrial Commercial 7% 6% • per capita daily 11% consumption: o 105 L/day (2008), o 115 L/day (2009), 76% o 127 L/day (2010, 2011) (HUEWACO, 2012). Public piped water use by sectors o 123 L/day in 2011 in 2011 (HueWACO) (survey on 300 households) GEOSS-AP/AWCI Session, Tokyo, May 27th 2014
3. Water use and supply in Hue 3.2. Water supply • HueWACO: only one water supply company • 23 purification plants with total capacity of 185,000 m 3 /d for the whole province (2102) • 3 purification plants located in Hue city with 114,500 m 3 /d • Total length of network > 1600 km • Water source: 100% surface water • Water leakage <12%. GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 14
3. Water use and supply in Hue Tap water quality • Meets all requirements by National Technical Regulation on Drinking Water Quality (QCVN 01:2009/BYT) • Particularly, turbidity always 10 times lower than limitation value (0.2 NTU vs. 2.0 NTU) • Declared Water Safety Plan in 2008 (one of three companies in South-East Asia recognized by WHO) GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 15
4. Wastewater management in Hue 4.1. Wastewater generation • Domestic WW major, industrial WW minor – Domestic WW: 36,600 m 3 /d – Industrial WW: 2,000 m 3 /d (our estimation based on water balance, 2010) • Domestic wastewater generation – 108 L/cap/d (our estimation, above mentioned) – Standard design value for for I-class city: 120 L/cap/d (Vietnam Building Code QCVN 01:2008/BXD) GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 16
4. Wastewater management in Hue Households 38,812 m 3 Huong River Public water supply system 40,364 m 3 48,466 m 3 44,104 m 3 Water leakage Well water In-plant use 12% = 5,259 m 3 4% population 9% = 4,362 m 3 Sewer 4, 832m 3 Grey water 90% 10,989 m 3 31,496 m 3 36,328 m 3 36,629 m 3 Open channel Water Septic tank 301.4 m 3 Excreta (urine) bodies 10,989m 3 347.6 m 3 Culvert Seepage 8% 14,652 m 3 3,229 m 3 Water balance for Hue city (daily based) (2010) GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 17
4. Wastewater management in Hue 4.2. Domestic wastewater characteristics 2006- 2010- 2015 design National Parameter 1997 2005 2007 2011 values regulation COD, mg/L 170 223 298 181 300 N.A BOD 5 , mg/L 115 151 213 86 200 30 SS, mg/L 77 113 155 37 250 50 T-N, mg/L 25 15 20.9 29 40 30 (NO 3 -N) T-P, mg/L 11 9 1.7 3 5 6 Our QCVN Hop et al., HEPCO, HEPCO, HEPCO, Data source survey, 14:2008/ 1997 2007 2007 2007 2011 BTNMT Domestic WW in Hue is not so strongly polluted in terms of organic and nutrient contents. GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 18
4. Wastewater management in Hue 4.3.Sewerage and drainage network – Combined system – Components: • 81 km of ditches, 127 km of sewers, 9035 manholes • 16 km canals and rivers, • 40 ponds – Service coverage: ~ 30% – Gravity-principal operation (HEPCO, 2013) HEPCO: Hue Urban Environment and Public Works State-owned Co.Ltd. GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 19
4. Wastewater management in Hue In Hue Citadel: ponds and Sewers& Ponds canal play Manholes important role as drainage function Huong River GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 20
4. Wastewater management in Hue Inundation due to poor drainage system • Several times a year • Estimation: rain at probability of 50%, 72 mm in 3 h 70% of streets under 0.1 – 0.5 m (Provincial Dept. of Transportation) Inundated after heavy rain (Oct., 2007) Inundated after heavy rain (Oct., 2009) GEOSS-AP/AWCI Session, Tokyo, May 27th 2014 21
Recommend
More recommend
