E2993 V3 Viet Nam Managing Natural Hazards Project (VN-Haz/WB5)

Environmental Assessment (EA) E2993 v3 Viet Nam Managing Natural Hazards Project (VN-Haz/WB5)

ANNEX 3 Background on Key River Basins

Public Disclosure Authorized 1. This annex provides environmental background in key river basins (Ma, Ca, Ha Vang-Rac, Gianh- Nhat Le, Thach Han, Vu Gia - Thu Bon, Tra Khuc - Tra Bong, Kone, and Dinh). The data includes natural features (climate, flow and flood, salinity intrusion), ecological features and cultural sites, water quality, and socio-economic conditions. This information was used as the basis in assessing the potential impacts of the Project.

A3.1. Environmental Background in Ma River Basin A3.1.1. Natural features 2. Ma River originates from the Northern side of Pu Huoi Long mountain range at an elevation of 2,179 meters (m) in Tuan Giao, Dien Bien province, continues in northwest – southeast direction across Son La, Sam Nua (Lao PDR), Hoa Binh, Thanh Hoa, and discharges into the Pacific Ocean through the Sung, Lach Truong and Cua Hoi tributaries. The Ma River basin system also includes three rivers, Chu River, Buoi River, Public Disclosure Authorized and Cau Chay River, all joining Ma River in Thanh Hoa Province in the Central Vietnam. 3. Ma River is a 512 kilometers (km) long river, with a basin area being the fifth largest in Vietnam, after Mekong River, Hong – Thai Binh River, Dong Nai River and Ca River. The total drainage area of the basin is 28,400 square kilometers (km2), of which 17,720 km2 lies within Vietnam’s territory, making up 62% of the total river basin area. Climate 4. The average temperature in the Ma River basin is relatively high throughout the year. The average temperature recorded at the 14 meteorological stations within the Ma River basin varies spatially ranging from 20.9-23.oC, reflecting the topographical characteristics and altitudes of the locations. 5. Annual rainfall is substantial with dominant winds from south and southeast during May to September months. The historical data recorded in the Ma River basin (1961-2007) show some special Public Disclosure Authorized variability in climatic conditions in annual rainfall of 1,165-1,966 millimeters (mm) with 80% of the rainfall occurring during the monsoon (May to September) season. The average annual rainfall ranges from 1,200 to 1,700 mm per year (mm/year) in the upstream area, 1,500-1,600 mm/year in the middle stream area, 2,000- 2,200 mm/year in the upstream area of Chu River, and 1,600-1,800 mm/year in the lowland area. The rainy season in the upstream areas begins in May and ends in October, while that in the Chu river basin is from late August to early November. 6. There are two factors that influence the wind characteristics in the Ma River basin: the southeast winds in summer, originating from the Bay of Bengal, which increases the density of water vapor leading to monsoon rains; and the presence of two parallel mountain ranges surrounding the Ma River basin that partially blocks incoming air from the southwest in summer or from the north in winter. The average annual wind speed in meters per second (m/s) in the Ma River basin indicates no big spatial variations in wind speed: on an average, the lowest value corresponds to Tuan Giao (0.7 m/s) and the highest value to Moc Chau (2 m/s).

Public Disclosure Authorized 7. The river flow varies greatly in time and space. In general, the distribution of flow of large and medium rivers follows a one-peak pattern with the highest flow rate occurring in September or August. However, the flow of small rivers in Chu river basin follows a two-peak pattern, with a second peak in May or June. The river flow in cubic meters per second (m3/s) varies quite greatly in Cam Thuy. The average discharge in April (111 m3/s) is only one-third of the annual discharge (334 m3/s) and one-seventh of the

Environmental Assessment (EA) Viet Nam Managing Natural Hazards Project (VN-Haz/WB5) highest average discharge (in August). Data show that the highest discharges monitored at Cua Dai, Xuan Khanh and Cam Thuy are 442 m3/s and 1,713 m3/s, respectively, and 258 times higher than the lowest discharges at the same gauging station. Flow and floods 8. The flood season varies across the Ma River basin, from June to October across Ma River, from June to November in the upper area of Chu river, and from July to November in the Chu River’s lowland area. The total runoff in flood season accounts for 65-80% of the total annual runoff. Each year, Ma River’s total runoff to the sea equals 18 billion m3/year. The flow is unevenly distributed. 9. In the dry season, the runoff is only 4,76 billion m3, making up 26% of the total annual runoff. Meanwhile, the 4 months of the flood season make up 74% of the total annual runoff. The driest period is between February and April, which comprises 8% of the annual flow. March tends to have the lowest flow rates, contributing only 2.4% of the total. The total runoff per person in the Ma river basin is over 4,100 m3/person, only slightly higher than the standard (4,000 m3/year), however, this number will be considerably reduced if the flows coming from outside the country (22% of the runoff) are excluded, and the average total water supply per person goes down to only 1,080 m3/person. Salinity intrusion 10. Salinity intrusion is influenced by tides and river flows. In the dry season, the salinity intrusion in the downstream part of Len River can extend up to 20-25 km from the river mouth. Salt water intrusion reaches Yen On along Len River, Mi Quang Trang along Can River and Tuan T-junction along Ma River. The entire Lach Truong River always saline in the dry season. On Ma River, at Ham Rong, the salinity rises up to 6 %o in 2-3 hours when the tides peak, up to 0.1%o half tide at Tuan T-junction. On Len River, the salinity is at 0.1%o. The intrusion even reaches Bao Van in several years. The salinity intrusion in Lach Truong River often reaches Xiphong Cu Da in the dry season. A3.1.2. Ecological features and cultural sites 11. Ma River basin’s ecosystem is characterized by both Northwest and North-Central ecosystems. Evergreen forests are the typical type of natural forests of the basin. There are 7 conservation areas within the river basin: i) Pu Hu Nature Reserve (35,089 ha); ii) Pu Luong Nature Reserve (17,662 ha); iii) Ben En National Park (16,634 ha); iv) Xuan Liem Natural Reserve (23.61 ha); v) Xuan Nha (38,069 ha); vi) Pa Co- Hang Kia (7,091 ha); vii) Cuc Phuong National Park (22,200 ha). Conversation area index is estimated at 5.66%, which is of low-medium level compared to other basins. The index indicates that the conservation value and environmental assets in the basin are at low-medium level. 12. Basin forest cover rate is estimated 44% at medium level, compared to other basins. The rate indicates important role for sustaining river basin processes. Basin native forest rate is high 77.3% that indicates good forest quality and good catchment processes for runoff and water quality. However, it is generally acknowledged that the quality of natural forests continues to be more fragmented and degraded. Most of the natural forests are considered poor or under recovery; significant forest fragments remaining are mostly in Nature Reserves, National Parks. 13. There are 4 Historical/Cultural Sites approved by The Government in the Basin. Heritage Index of Ma basin is of medium level. Table A3.1: Ecological features of Ma river basin

Total area: 28,400 km2 of which 17,720 km2 are located in Vietnam Environmental health: Biodiversity and ecosystems

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Characteristics Included: terrestrial and aquatic ecosystems  Ma river basin’s ecosystem is characterized by both Northwest and North-Central ecosystems. Evergreen forests are the typical type of natural forests of the basin; lowland evergreen forests now only remain in some areas of Ben En National Park Conservation There are 4 Conservation areas, including National Parks, Nature Reserves recognized by areas The Government in the Basin  Conversation area index is estimated at 5.66%, which is of low-medium level compared to other basins. The index indicates that the conservation value and environmental assets in the basin are at low-medium level Historical/  There are 4 Historical/Cultural Sites approved by The Government in the Basin Cultural Site  Heritage Index of Ma basin is of medium level (4), compared to other basins.

Major water 1. Sop Cop Nature Reserve related Location, area, water source environmental Area: 27,886 ha assets  Sop Cop Nature Reserve is located in Song Ma district in the mountainous north-west of Vietnam. The topography of the nature reserve is steep and mountainous, and elevations range from 450 to 1,940 m. The nature reserve is fed and drained by tributaries of the Ma river.  The natural vegetation has been extensively cleared and replaced by scrub. However, it appears that areas of evergreen forest still remain at high elevations.  The fauna was previously very rich, and the site supported a high diversity and abundance of large mammal species, including, in the 1950s, a species of rhinoceros. However, faunal diversity at the site has decreased in recent years.  Forest at Sop Cop Nature Reserve protects the catchments of streams that provide local communities with water for irrigation and domestic use. 2. Ben En National Park Location, area, water source Area: 16,634 ha  Ben En National Park is located in Nhu Thanh and Nhu Xuan districts, Thanh Hoa province. The national park is situated in a region of low hills surrounding an artificial lake. Altitude ranges from 20 to 497 m, with most areas being below 200 m. The lake is 50 m above sea level and covers 2,281 ha. The geology of the national park is characterized by sedimentary rocks, particularly mudstone. Small areas of limestone are also present, and impressive limestone karts formations can be found in the buffer zone in north-east boundary of the national park.  The core zone of the national park is fed and drained by the Muc river, while the proposed extension to the national park is fed and drained by the Chang river  Ben En National Park is moderately important for the conservation of biodiversity. The national park protects one of the few surviving areas of lowland evergreen forest in north-central Vietnam. The forest has, however, been extensively disturbed in the past by commercial logging operations, and, as a result, is characterized by small, shade- intolerant trees and a dense undergrowth dominated by bamboo. However, since the cessation of commercial logging, forest quality has improved  There are 870 species of high plant, 375 species of fauna, including amphibian, reptile, mammal and bird (1998), in which a number of globally threatened trees and mammals

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have been recorded at the national park Physical  Forest cover: 44% condition  Agricultural cover: 20% Land use  Resident cover 3%  Specific use 4% Proportions  Other use 29% Vegetation  Vegetation Index of Ma River Basin occupies 6.18% of total national forest area. – cover Lower than other basins. This basin take a less important role to meeting the national forest target  Basin forest cover rate is estimated 44 % at medium level, compared to other basins. The rate indicates important role for sustaining river basin processes  Basin native forest rate is high 77.3% that indicates good forest quality and good catchment processes for runoff and water quality. However, it is generally acknowledged that the quality of natural forests continues to be more fragmented and degraded. Most of the natural forests are considered poor or under recovery; significant forest fragments remaining are mostly in Nature Reserves, National Parks

A3.1.3. Water quality 14. According to the annual Environmental Reports of Thanh Hoa province in the past few years, the water quality of four rivers – Ma river, Len river, Cau Tao river and Chu river – within Ma river basin is generally good. Water quality analysis performed at the 20 monitoring locations on these rivers show no signs of contamination by heavy metals, for example, with the content of Cd and As ranging from below 0.001 mg/l- 0.002 mg/l and below 0.001 mg/l-0.01 mg/l, respectively, which are below the national standard (QCVN 08:2008/BTNMT). However, at some monitoring locations, the BOD value, varying between 2.3 mg/l-8.9 mg/l, has exceeded the permissible limit for Grade A water (4-6 mg/l), but still very low compared to the standards for Grade B water (15-25 mg/l). The COD value, in the orders of 3.2 mg/l-12.5 mg/l, is below the permissible limit for Grade A water (10-15 mg/l) according to QCVN 08:2008/BTNMT. Based on evaluation, the surface water in Ma river basin has shown signs of light pollution from organic substances in some river sections passing through residential and industrial areas. Table A3.2: Surface water quality parameters in Ma river basin Monitoring location Monitoring parameters

COD BOD NO3- SS Cd As Coliform (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (MPN/ml) Na Sài 3,5 2,4 0,78 156 <0,001 <0,001 150 Cửa Hà, Cẩm Thủy 4,5 3,2 <0,01 150 <0,001 <0,01 150 Cầu Kiểu 5,9 4,2 1,36 250 0,001 <0,01 130 Cầu Vạn Hà 6,8 4,9 <0,01 110 <0,001 <0,01 210 Ngã ba Bông 3,2 2,3 0,68 148 0,001 <0,01 130 Làng Giàng 6,3 4,8 0,9 380 0,001 <0,01 220 Cầu Hoàng Long 4,9 3,8 <0,01 320 0,001 <0,01 240 Cảng Lễ Môn 8,5 6,2 6,2 5520 0,002 <0,01 480 Cửa Hới 7,8 5,6 5,8 25.640 0,001 <0,01 120 Cầu Tào 8,6 5,9 1,82 1440 0,001 <0,01 180 Cầu phao Bút Sơn 9,8 7,3 1,45 1630 <0,001 <0,01 150 Gũ - Nga Sơn 4,8 3,4 0,12 169 <0,001 <0,01 170

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Monitoring location Monitoring parameters

COD BOD NO3- SS Cd As Coliform (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (MPN/ml) Đò Thắm 9,2 6,4 1,12 1970 0,001 <0,01 110 Đập Bái Thượng 4,5 3,2 <0,01 105 <0,001 <0,01 120 Dưới cửa xả KCN Mục Sơn 4,5 3,1 <0,01 118 <0,001 <0,01 120 Dưới XN giấy QĐ 12,5 8,9 2,25 380 0,001 <0,01 720 Giáp ngã ba Bông 6,4 4,3 0,01 240 0,001 <0,01 160 Trên cửa xả KCN Mục Sơn 9,4 6,4 1,78 322 <0,001 0,01 690 Cầu Mục Sơn 8,5 6,9 3,6 250 0,001 <0,01 190 Thị trấn Thọ Xuân 5,8 3,6 0,68 145 0,001 <0,01 130

A3.1.4. Socio-economic conditions

Economic conditions 15. Thanh Hoa accounts for most of the area of this river basin. GDP accounts for 2.83% of the national GDP. Its economic structure is: agriculture 35%, industry 32% and service 33%. For the last 5 years, its annual GDP growth is 10.1%. The area of agriculture and cultivation land is insignificant, of which, paddy area makes up 65%. The yearly paddy production is low. Livestock output only accounts for 25% of the agriculture sector’s GDP. Forestry land makes up 75% of the province’s area, the production value, however, is not high. Aquaculture, mainly cultivation on the coastal area and catching on the rivers, is developing fast. Industry is of slow development. The main industries are sugarcane and material manufacturing. Nghi Son Cement Factory and Nghi Son Industrial Park are the two major industrial units in the province. Tourism and commerce are also of slow growth and small scale. Sam Son is the main tourism spot. Social conditions – Population: Up to 2006, the population of Ma river basin is 4382.6 thousand, making for 5.21% of the whole country’s total population. The average population density is 247 people/km2. The average population growth rate of the basin is 1.11%. – Ethnicity: The ethnic minorities account for 25.55%, of which, 14.4% is in Thanh Hoa and 13.25% in Nghe An. Ethnic minorities live mainly in rural and remote areas and on self-sufficient agriculture. – Poverty rate: The average poverty rate of the basin is up to 53.8%, and virtually three times higher than the average poverty rate of the whole country. In the basin, the highest poverty rate is of Nghe An: 40.8% (of which, poverty rate of Que Phong district amounts to 83.41%) and the third is Thanh Hoa: 35.65%. – Employment: Emloyment concentrates mostly in the agriculture sector. Industry and service sectors are underdeveloped. The most developed industry is in Thanh Hoa and concentrates mainly in the urban area: Thanh Hoa City. A3.2. Environmental Background in Ca River Basin A3.2.1. Natural features 16. Ca river is an international river and Ca river basin is a large river basin in Vietnam. The river lies between latitude 18015’00’’ and 20010’30’’ North and between longitudes 103045’20’’ and 105015’20’’ East. The main flow of Ca river originates from Muong Khut, Muong Lap in Lao PDR, at over 1800-2000m height, it continues in northwest – southeast direction, enters Nghe An at Keng Du and flows into the sea through Hoi

Environmental Assessment (EA) Viet Nam Managing Natural Hazards Project (VN-Haz/WB5) river mouth. In the upstream, the river bed is narrow and steep, with many falls, while in the midstream (from Con Cuong to Anh Son), the river bed expands and receives Hieu river from the left bank; the downstream section flows through the plain area, receives La river from the right bank and then flows into the sea through Cua Hoi. The total basin area is 29,930 km2, including 20,460 km2 in Vietnam’s territory. Climate 17. The average rainfall in the river basin is around 1,700-1,800 mm/year. Several locations with high rainfall reach 2,200 mm/year in La river basin, 2,000-4,000 mm/year in Giang river basin. In the dry season, the rainfall makes up only 35% while 4 months of the rainy season make up 65% of the total annual rainfall. Flow and floods 18. The river flow is determined by rainfall and typographic conditions of the river basin. Low flow rate in Ca river (at Yen Thuong) lasts for 7 months (December – June), while the high flow rate lasts for 5 months in a year (July – November). At Yen Thuong, the lowest average monthly flow rate is approximately ¼ of the average annual flow rate and 1/10 the highest average monthly flow rate. The total annual runoff of Ca river is 23.5 billion m3, of which 20.5 billion m3 (87%) is originated in the territory of Vietnam. The rest 3.0 billion m3 (13%) is originated from Laos. The average annual water availability per capita in Ca river basin is 6,050 m3/person/year, 1,5 times as much as the standard set by the International Meteorological Organization (4,000 m3/person/year). In the dry season, this figure is 1.760 m3/person/year. 19. In the basin, there are 2 flood periods, May rain-flood period in May – June, and main flood season in September – November. The main flood season starts and ends at different time on different river branches. Towards the main flow, floods start from June to October or November. Towards La river, floods start in August and end in December. Floods on Lam river last from June to December. Floods on Ca river branches never occur at the same time, especially big floods. Double floods often occur on branches of Hieu river and Ca river, while single floods often occur on Giang river and La river. Salinity intrusion 20. According to monitoring figures of the month April in several years from the Institution of Water Resources Planning, salinity limit of 10/00 reaches Duc Xa sluice on La river and it reaches Yen Xuan bridge on Ca river. The salinity limit in the tidal areas depends on the discharge from the upstream and wind direction at the river mouth. If the discharge at Yen Thuong reaches 150-180 m3/s, the salinity of 10/10 only appears in 2-3 hours at Duc Xa, Cho Chang, and 6-8 hours at Trung Luong. But if the discharge at Yen Thuong is below 100 m3/s, the salinity of 10/00 appears in 3 hours at Yen Xuan, 6 hours at Cho Chang, and 12 hours at Trung Luong. This indicated that the supplement for upstream discharge to push out the salinity is necessary. A3.2.2. Ecological features and cultural sites 21. Ca river basin’s ecosystem is characterized by North-Centre ecosystems. Lowland and lower mountains evergreen forest is the typical type of natural forests in the basin. There are 3 Conservation areas, including National Parks, Nature Reserves approved by The Government in the Basin. i) Pu Mat National Park (91,113 ha); ii) Vu Quang National Park (55,029 ha); iii) Pu Mat National Park (46,600 ha). Conversation area index is estimated at 10.78%, which is at high-medium level, compared to other basins. The index indicates the conservation value and environmental assets in the basin are at high-medium level. 22. Basin forest cover rate is estimated 40 % at medium level, compared to other basins. The rate indicates important role for sustaining river basin processes. Basin native forest rate is high 76.3% which indicates good forest quality and good catchment processes for runoff and water quality. In addition, nature forest is still good because primary forest area is still high.

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23. There is 1 Historical/Cultural Site approved by The Government in the Basin. Heritage Index of Ca basin is low. Table A3.3: Ecological features of Ca river basin Total area: 29,930 km2 of which 20,460 km2 are located in Vietnam Environmental health: Biodiversity andecosystems Characteristics Included: terrestrial and aquatic ecosystems

 Ca river basin’s ecosystem is characterized by North-Centre ecosystems. Lowland and lower mountains evergreen forest is the typical type of natural forests in the basin;  The basin is in North Central Region, a typical feature of the region is the long but narrow strip of land between the Annamite Range and the sea. Rich forests still cover a long strip of the Annamite Range, near the Lao border. Conservation  There are 3 Conservation areas, including National Parks, Nature Reserves approved by areas The Government in the Basin  Conversation area index is estimated at 10.78%, which is at high-medium level, compared to other basins. The index indicates the conservation value and environmental assets in the basin are at high-medium level Historical/  There are 1 Historical/Cultural Sites approved by The Government in the Basin Cultural Site  Heritage Index of Ca basin is low (1), compared to other basins. Major water 1. Pu Mat National Park related Location, area, water source environmental Area: 91,113 ha assets  Pu Mat National Park is situated in the northern Annamite Range. Elevations at the national park range between 100 and 1,841 m, although 90% of the national park is under 1,000 m in elevation.  The national park is fed and drained by four main rivers: the Khe Thoi, Khe Bu, Khe Choang and Khe Khang. All four rivers feed the Ca river, which runs from west to east, through a wide valley to the north of the national park.  Forest at Pu Mat National Park protects the catchments of four rivers, which, collectively, are the main source of water for irrigation and domestic use for communities in the buffer zone. In addition, the forest at Pu Mat protects part of the watershed of the Ca river, the major river in southern Nghe An province.  There are 2469 species of plant, 938 species of fauna (120 species of mammal, 295 species of bird..) Especially, Pu Mat is probably one of the most important sites for mammal conservation in Vietnam (discovered Sao La Pseudoryx nghetinhensis); 37 mammal species are listed in Global and Vietnamese Red Book.  Pu Mat National Park preserves one of the best examples of the Annamite mountains ecosystem, and is of international conservation significance. The national park supports one of the largest remaining blocks of natural forest in northern Vietnam, and is linked to other protected areas in Vietnam and Laos by contiguous areas of forest. 2. Vu Quang National Park Location, area, water source Area: 55,029 ha  Vu Quang National Park is located in Huong Son and Huong Khe districts, Ha Tinh province and is situated in the northern Annamite mountains. The national park contains

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an elevation gradient of over 2,000 m, from 30 m in the lowlands in the north-east of the national park to 2,286 m at the summit of Mount Rao Co, on the border with Laos.  The National Park is fed by three rivers: the Nam Truoi, Rao No and Khe Tre rivers. These rivers originate in the south of the national park, as steep, narrow, fast-flowing streams  There are 465 species of high plant and 70 species of mammal, 273 species of bird, in which a number species are rare and valuable ones  The Site to be considered to be of the highest regional importance for bird conservation Physical  Forest cover: 40% condition  Agricultural cover: 19% Land use  Resident cover 1% Proportions  Specific use 4%  Other use 27% Vegetation  Vegetation Index of Ca River Basin occupies 6.45% of total national forest area. – cover Lower than other basins. This basin take a less important role to meeting the national forest target  Basin forest cover rate is estimated 40 % at medium level, compared to other basins. The rate indicates important role for sustaining river basin processes  Basin native forest rate is high 76.3% which indicates good forest quality and good catchment processes for runoff and water quality. In addition, nature forest is still good because primary forest area is still high.

A3.2.3. Water quality 24. Monitoring results of Ha Tinh and Nghe An provinces in recent years show that, at monitoring locations on Quyen, La, Lam rivers and Cua Tien dug river, signs of water pollution from heavy metals such as Cd, Pb haven’t been discovered. However, the BOD value at those monitoring locations has exceeded permissible limits of QCVN for Grade A water, although still within limit for Grade B water. Coliform value has exceeded QCVN for Grade B water at some locations such as Tay Yen bridge (Ky Anh district, Ha Tinh province) and Duoc brigde (Nghe An).

Table A3.4: Water quality parameters in Ca river basin No. Parameters Quyền river (Tây La river (Thọ Tường Lam river (Ben Cửa Tiền dug river Yên Bridge, Kỳ Anh, bridge, Đức Thọ, Ha Thuy bridge, (Đước bridge, Ha Tinh) Tinh) Nghe An) Nghe An) 1 COD (mg/l) 28,7 22 10,1 12,2 2 BOD (mg/l) 18,4 17,2 5,7 6,58 3 DO (mg/l) 5,6 6,3 5,03 4,58 4 NH4+ (mg/l) 0,54 0,41 0,41 0,39 5 NO3- (mg/l) - - 3,66 4,06 6 PO43- (mg/l) - - 0,04 0,12 7 SS (mg/l) 29 37 34 42 8 Pb (mg/l) - - KPH KPH 9 Cd (mg/l) - - KPHK KPH 10 Coliform 12.600 580 700 11000 (MPN/ml)

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A3.2.4. Socio-economic conditions

Economic conditions 25. Ca river basin basically consists of Nghe An and Ha Tinh. GDP of this basin accounts for 2.97% of the national GDP. The economic structure is: agriculture 38%, industry 26% and service 36%. The average annual GDP growth rate for the past 5 years is 9.8%. – Agriculture: the average rice yield is 40 tons/ha (2002). Livestock mainly focuses on small-scale breeding of animals and pigs of households. – Industry: some industries have recently been formed such as cement, sugarcane and steel. Vung Ang Industrial Park has great potential for economic development. – Aquaculture: face a good deal of difficulties regarding water sources. – Tourism and trade: small-scale and slowly developing.

Social conditions 26. Population: The basin’s population scale is 3883.5 thousand people, making up 4.6% of the national population. The Ca river basin’s population includes all the population of Nghe An except for 50% Que Phong district’s population (belong to Ma river) which accounts for 78% of the total population of the basin. Then comes Ha Tinh: 20% (except for Thach Ha, Cam Xuyen and Ky Anh district). Thanh Hoa only accounts for 2% - which is half of the population of Nhu Xuan district. The average population growth rate is nearly 1.3%. About 20% of the population is in city and urban area while 30% is in the highlands and high mountainous area. The average population density of the basin is 190 people/km2 while the delta’s population density is 453 people/km2. The population density of Nghe An is 186 people/km2 and Ha Tinh is 217 people/km2. The average population growth rate of the basin is 0.88%. It shows that people in the basin continues to emigrate to other regions in the recent years. 27. Ethnicity: 9.58% of the basin’s population is ethnic minority, living mainly in the mountainous and remote districts of 3 provinces – Thanh Hoa, Nghe An and Ha Tinh - especially Thanh Hoa. Ethnic composition consists of Chut, Muong, Thai, Tay and Nung, etc. 28. Poverty rate: Poor households of this basin accounts for up to 47%, rank third after Ma river and Srepok river. The highest poverty rate is of Tuong Duong district (Nghe An): 96%, followed by Ky Son commune: 93%, which is 4.5% times higher than the general poverty rate of the whole country.

A3.3 Ha Vang river and Rac river basin (Ha Tinh) 29. The entire Ha Vang and Rac river basin is in the area of Ha Tinh province. Ha Vang is a small river in Ha Tinh province. It rises from Ho Do bridge, Ho Do commune, Thach Ha district, which is the crossover of Nghen river and Ho Do river. From this position, the river runs to the North-eastern direction and pours into the Eastern Sea through the Sot estuary under Thach Kim commune, Thach Ha district. The river has the length of relatively 12 km and wide river bed, the widest is about 2 km which is the solely waterway from Ha Tinh city to the Eastern Sea. See Figure A2.3 (Annex 2) for Ha Vang – Rac river basin map. 30. This basin has the climate condition of the North Ngang pass of North Central coastal region. Each year, it is heavily affected by the North-east monsoon. This region’s main characteristic is cold winter and dry and hot summer. The North-east monsoon blows from June, July to April of the following year. The region’s rainy season begins in August and ends in November of the following year. As for period of time, the rainfall usually concentrates in September, October and November. In these 3 months, rainfall accounts for nearly 70% of the total

Environmental Assessment (EA) Viet Nam Managing Natural Hazards Project (VN-Haz/WB5) yearly rainfall, but September and October’s proportion amounts to 69% of the total rainfall of the above three months. Spatially, rainfall tends to gradually increase from the North to South. A3.4 Gianh and Nhat Le river basins (Quang Binh) 31. Gianh river basin has the natural area of 4,680 km2, including Ron river, Gianh river, Ly Hoa river and Dinh river in the vicinity of four districts - Quang Trach, Bo Trach, Minh Hoa and Tuyen Hoa - of Quang Binh province and six communes of Ky Anh district, Ha Tinh province. The research area is limited to: the North borders with Rac river basin , Rao Cai river, Ngan Sau river of Ha Tinh province; the South borders with Nhat Le river basin of Quang Binh province; the West with Laos and the East with the Eastern Sea . 32. The Nhat Le River is a river in Dong Hoi, Quang Binh province. The Nhat Le River is 152 km long, of which the Kien Giang river is 58 km in length, and the Long Dai river is 77 km long. The river is formed by the confluence of the Kien Giang river in Le Thuy district and the Long Dai river in Quang Ninh district. The Nhat Le River flows northeast (unlike most rivers in Vietnam, which run southeast) before emptying into the South China sea. At the mouth of this river are several white fine sand beaches which are popular tourist attractions. 33. Gianh and Nhat Le river basins terrain are narrow and steep from the West to East. Hills and mountains account for 85% of the total natural area. Its topography is diverse. The West of the province is mountainous area of the height from 1,000-1,500 m, next to it is low hill area, scattered in an upside down bowl shape. There is a small and narrow strip of plain near the coast line. Last are coastal strips of sand with the shape of sickle. 34. Dry season is from April to August. Rainy season is from September to March of the following year, flood season in the western slope of the Truong Son is from July to October and the high season is usually from September to December. The average annual rainfall is from 2000 – 2,300 mm. 35. Gianh and Nhat Le river basins’ ecosystem is characterized by the limestone forest ecosystem. There are only one Conservation area, that is Phong Nha-Ke Bang National Park (85,754 ha), that approved by The Government in the Basin. Conversation area index is estimated 18.32% is high level, compared to other basins. The index indicates the conservation value and environmental assets in the basin is high level. 36. There are no Historical/Cultural Sites in the Basin. It indicates there are insignificant heritage/ cultural and historic assets in the basin. A3.5 Thach Han river basin (Quang Tri) 37. Thach Han river basin is 155 km in length; the largest valley area is 2,660 km2. The main river branch is Thach Han which is derived from the big mountains of Dong Sa Mui, Dong Voi Mep (Rao Quan branch) and Ba Le cavern, Dang cavern (Dakrong branch). Thach Han river pour into the sea through Viet estuary. The map of Thach Han river basin - Ben Hai is presented in Figure A2.5 (Annex 2). 38. The rainy season occurs from September to January of the following year, the rainfall is about 75-85% of the total yearly rainfall. There are usually heavy and prolonged rains from September to November (approximately 600 mm). The months with the least rainfall are February and July (40 mm/month for the least). The total annual rainfall ranging from 2,000-2,700 mm, the number of rainy days is 130-180. The stormy season in Quang Tri occurs from July to November, of which, September and October have the most storms. 38. Thach Han river basin’s ecosystem is characterized by the tropical closed forest. There are no conservation area in the basin. It indicates the conservation value and environmental assets in the basin is very low. 39. There are one Historical/Cultural Sites in the Basin that is Thanh Co Quang Tri. It indicates there are less significant heritage/ cultural and historic assets in the basin.

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A3.6. A3.6.1. Natural features 40. Vu Gia – Thu Bon river basin is one of the largest basin in the Central Coast, located on the Eastern side of the Annamite Range. The basin lies between latitudes 16055' and 14055’ North, and longitudes 107015' and 108024' East. The dominant direction of slope of the basin is northwest – southeast, with an average gradient of 25,5%. The upstream area is high mountains of 1,700-2,045m height, which form an arc around the entire northern, western and southern parts of the basin. The downstream area is the coastal lowlands. The total basin area is 10,350 km2, including 560.5 in Kon Tum, the rest loes mainly within Quang Nam province and Da Nang city. Vu Gia – Thu Bon river basin lies within the tropical monsoon area, deeply influenced by typographic elements, therefore, the area has an unusual climate. Climate 41. The average annual rainfall ranges from 2,000 to 4,000 mm/year and decreases from the mountains to the lowlands. Mountain sides facing winds have significantly high rainfall, in contrast, the sides hidden from the winds received much lower rainfall. In the lowlands, the annual rainfall is around 2,000 mm, such as in Da Nang (2,051 mm), Hội An (2,058 mm), meanwhile rainfall in the mountainous areas are higher, such as in Bà Nà (2,341 mm), Nông Sơn (2,634 mm), especially in high mountains such as Thu Bon upstream area, where the typography facing the winds has formed places of high rainfall such as Trà My (3,738 mm/year), Tiên Phước (2,833 mm/year). 42. The dry season lasts for 8 month from January to August, when rainfall makes up only 20-35% of the total annual rainfall. February, March and April are months with lowest rainfall, at only 10-30 mm in the lowlands and 30-100 mm in the mountains. 43. The rainy season, when northeast monsoon winds prevail in the basin, begins in September and ends in December, later than the North and the South regions. In the rainy season, the rainfall accounts for 65-80% of the total annual rainfall. Months with highest rainfall are October and November, making up 40-50% of the total annual rainfall. Flow and floods 44. The flow in the river basin is divided into two separate seasons (flood season and dry season). The flow variations in Vu Gia – Thu Bon river basin are quite complicated, the annual flow in high flow years can be 4 to 8.25 times higher than that in low flow years. Because of the seasonal characteristic, the distribution of flow is uneven in different months in the year, with big difference between high season month and low season month. 45. The lowest discharge is in April or August. The runoff in the dry season makes up 21.8-38.5% of the total annual runoff. The month with the lowest runoff is April, making up only 2.1-2.6% of the total annual runoff. Area with the highest discharge in the dry season is the upstream Thu Bon river, area with the lowest discharges are the North and Northwest of the basin. The dry season is divided into two periods: 46. Floods in Vu Gia – Thu Bon river basin are big and rapid due to the steep typography and high rainfall. The flood season often begins in mid-September and ends in early January in the next year. The flood season often begins and ends from half a month to a month earlier than the rainy season. The start and ending time of flood season and biggest floods are quite similar in Quang Nam province and Da Nang city. The runoff in flood season makes up 62.5-69.2% of the total annual runoff. However, the flood time is not stable, in many years, floods can happen from September to January of the next year. The highest flood discharge monitored is 10,600 m3/s (4/12/1999) in Nong Son and Thành Mỹ 7,000 m3/s (20/11/1998). Salinity intrusion

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47. The salinity intrusion in the rivers follows two cycles, corresponding with two high tide cycles, during which the saline water intrudes deeply in the rivers. During the low tides, deep salinity intrusion is less possible.

A3.6.2. Ecological features and cultural sites 48. Ecosystem of Vu Gia-Thu Bon river’s downstream: characterized by magrove forest ecosystems like coral reefs, seagrass beds and coastal lagoons, including wetlands with area of 500 ha in Cam Thanh, Cam Kim Communes and surrounding areas-Hoi An Town-Quang Nam Province. There are 3 Conservation areas, including National Parks, Nature Reserves approved by The Government in the Basin, which are Ba Na-Nui Chua National Park (Area: 38,210 ha). Conversation area index is estimated 3.84% which is at low-medium level, compared to other basins. The index indicates the conservation value and environmental assets in the basin are at low-medium level. 49. Basin forest cover rate is estimated at 49 % which is at medium level, compared to other basins. The rate indicates the important role of the forest cover to the sustainable growth of the river basin. Basin native forest rate is high 87% which indicates good forest quality and good catchment processes for runoff and water quality. In addition, nature forest is still good because the primary forest area is still high. 50. There are three Historical/Cultural Sites approved by The Government in the Basin, that are Hoi An Ancient town, Ngu Hanh Son and My Son Holy Land, in which The ancient town of Hoi An and the My Son Cham Holy Lands are two old cultural sites which are in the process of applying to the UNESCO for recognition as World Cultural Heritage. Table A3.5: Ecological features of Vu Gia – Thu Bon

Total area: 10,350 km2 of which 10,350 km2 are located in Vietnam Environmental health: Biodiversity andecosystems Characteristics Included: terrestrial and aquatic and wetland/mangrove ecosystems  Lowland and lower mountain evergreen forests are the typical type of natural forest ecosystem of Vu Gia-Thu Bon river basin;  Ecosystem of Vu Gia-Thu Bon river’s downstream: characterized by magrove forest ecosystems like coral reefs, seagrass beds and coastal lagoons, including wetlands with area of 500 ha in Cam Thanh, Cam Kim Communes and surrounding areas-Hoi An Town-Quang Nam Province Conservation  There are 3 Conservation areas, including National Parks, Nature Reserves approved by areas The Government in the Basin, which are Ba Na-Nui Chua National Park and Cu Lao Cham Nature Reserve  Conversation area index is estimated 3.84% which is at low-medium level, compared to other basins. The index indicates the conservation value and environmental assets in the basin are at low-medium level Historical/  There are three Historical/Cultural Sites approved by The Government in the Basin, that Cultural Site are Hoi An Ancient town, Ngu Hanh Son and My Son Holy Land, in which The ancient town of Hoi An and the My Son Cham Holy Lands are two old cultural sites which are in the process of applying to the UNESCO for recognition as World Cultural Heritage.  Heritage Index of Vu Gia-Thu Bon basin is high (3), higher than other basins. Major water 1. Ba Na-Nui Chua National Park related Location, area, water source environmental Area: 38,210 ha assets  Ba Na-Nui Chua Nature Reserve centred on Mount Ba Na, a 1,487 metre - high

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mountain on the border between Da Nang city and Quang Nam province. The National Park located in Hoa Ninh Commune-Hoa Vang District, west 38 km to Da Nang City  North-West part of the national park is fed and drained by streams - tributaries of Yen river, which flows to downstream of Vu Gia, then flows into the south of the Da Nang bay. South-East part of the National Park is fed anddrained by tributaries of Cu De river, which flows into the north of the bay  543 species of vascular plants have been recorded at Ba Na-Nui Chua Nature Reserve. These include 12 species listed in the Red Data Book of Vietnam  According to the investment plan, 61 mammal species, 178 bird species and 17 reptile species have been recorded at Ba Na-Nui Chua. (1994). Many of the species listed in the investment plan were also recorded during surveys by Frontier-Vietnam in 1994 and 1995, which recorded 472 vascular plant species, 29 mammal species, 106 bird species, 20 reptile species, six amphibian species, 33 fish species and 126 butterfly species. These include 44 rare and valuable fauna species listed in the Red Data Book of Vietnam  The forest at Ba Na-Nui Chua Nature Reserve protects the watersheds of the Ca De and Yen rivers. These rivers are an important source of water for irrigation, and domestic and industrial use in Da Nang city. Physical  Forest cover: 49% condition  Agricultural cover: 12% Land use  Resident cover 3%  Specific use 3% Proportions  Other use 33% Vegetation  Vegetation Index of Vu Gia-Thu Bon River Basin occupies 4.04% of total national cover forest area, lower than other basins. This basin takes a less important role to meeting the national forest target  Basin forest cover rate is estimated at 49 % which is at medium level, compared to other basins. The rate indicates the important role of the forest cover to the sustainable growth of the river basin  Basin native forest rate is high 87% which indicates good forest quality and good catchment processes for runoff and water quality. In addition, nature forest is still good because the primary forest area is still high.

A3.6.3. Water quality 51. Based on the surface water monitoring results through the years in Quang Nam province, some conclusions can be drawn out as follow: Most of the parameters of water in Tiên, Tranh, Ly Ly, Bến Giằng, Vu Gia – Thu Bồn rivers and Phú Ninh reservoirs are within the permissible limits, except the SS content in Tien and Tranh rivers which is 1.35 – 2.46 times higher than the limit. In short, the quality of surface water in most of the rivers and reservoirs in Quang Nam province is relatively good, except for Vinh Dien anh Truong Giang rivers, signs of pollution from TSS, BOD5, COD have been discovered and tend to increase. 52. Results from the Vu Gia river water quality monitoring program carried out by Da Nang DONRE in recent years show that most of the parameters are within permissible limits, except Coliform value exceeding Grade A limit by many times at all monitoring location. Overall, contents of pollutants in the river water such as BOD5, COD, SS, heavy metals such as Fe, Pb have reduced over the years. The Hg content in water,

Environmental Assessment (EA) Viet Nam Managing Natural Hazards Project (VN-Haz/WB5) although still within QCVN limit, is much higher than in previous years. Water quality in Vu Gia river within Danang city has been improved compared to previous years.

A3.6.4. Socio-economic conditions Economic conditions 53. This basin consists of Quang Nam province and part of Da Nang and Kon Tum. GDP accounts for 1.35% of the national GDP. 54. The economic structure is: agriculture 25%, industry 37% and service 38%. The average GDP growth rate for the past 5 years is 11.8%. In particular, agriculture: depends heavily on nature like water sources, floods and other natural disasters. In higher regions, the crop yield is lower, the cultivation area is unstable and there is only one crop per year. Aquaculture: is developing faster in recent years and focusing on raising tiger prawns in brackish water. Hydroelectricity: The area has a large hydropower potential, there has been some new constructions like Song Tranh 2, Dak Mi River 4, Con River 2 and the upcoming constructions such as the Song Bung 1, 4 and 5. Tourism: is developing fast with the tourism spots of Hoi An, My An and My Son being its great advantages. The long and beautiful coastline is a major potential for tourism exploitation. Industry: there are many industrial and economic zones such as Dien Nam - Dien Ngoc, Lien Chieu, Chu Lai etc. which have been invested in recent years. Da Nang itself developed into an economic center in the central region. Social conditions 55. Population: The population of the basin is 1787.6 thousand people, accounting for 2.12% of the national population and 2.4% of all river basins’ total population. The average population density of the basin is 113 people/km2. The population gathers crowdedly in Da Nang’s districts. Quang Ngai’s population density is 251 people/km2. The average population growth rate of the basin: The average population growth rate of the entire basin is 1.18%; 56. Ethnicity: Ethnic minorities make up 38.2%. The ethnic minorities gather mainly in Kon Tum: 53.63%, followed by Quang Nam: 6.80% and Da Nang 0.57%. 57. Employment in agriculture sector accounts for 44.52%, industry 19.37% and service 36.11%. The proportion of employment in service sector is relatively high compared to other river basins. Unemployment rate is 4.7%. 58. Poverty rate of the whole basin is: 38.2%, of which, poor households mostly concentrate in Kon Tum: 71.22%, then comes Quang Nam: 30.29% and Da Nang: 13.12%. A3.7. Environmental Background in Tra Khuc -Ve-Tra Bong River Basin

A3.7.1. Natural features 59. The Tra Khuc – Ve – Tra Bong river basin (Tra Khuc river basin) lies between latitudes 14050’ and 15020’ North, longitudes 108010’ and 109000’ East. Tra Khuc river basin spans 11 districts and towns of Quang Ngai and a part of Kon Plong district, Kon Tum province. The basin’s surface descends steadily from the West to the East, starting from the high mountains in Kon PLong district, Kom Tum province at a height of 1,300-1,500 m in the West, to the lowlands with an average height of 5-20 m. There is no significant change in typography between the highlands and the lowlands. The highlands and the lowlands are next to each other without nearly any transitory areas. This typographic feature creates straight flows from the highlands to the lowlands, which can easily cause floods in the rainy season and drought in the dry season. Tra Khuc – Ve – Tra Bong river basin area is 5,200 km2; Tra Khuc river is 135km long. Climate

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60. The average rainfall in the basin is about 2,890 mm. Rainfall tends to decrease from the North to the South and from the East to the West. High rainfall focuses in high mountains such as Ba Tơ, Gia Vực (3,200-4,000 mm/year), while rainfall in the coastal lowlands only reaches 2,300-2,700 mm/year. There is a significant difference in rainfall between the rainy season and the dry season. Rainfall is unevenly distributed throughout the year. The rainy season lasts in 4 months, from September to December, making up 70-80% of the total annual rainfall. High rainfall concentrates in October and November, accounting for 40-50% of the total annual rainfall. The dry seasons begins in January and ends in August, whose rainfall makes up 20-30% of the total annual rainfall. Months with the lowest rainfall are often February, April and August. 61. The rainy season here lasts for 4 months, but the flood season lasts only for 3 months and often begins 1 month later than the rainy season. The rainy season begins in September, but rainfall only accelerates in October and then, the flood season begins. The flood season lasts from October to December, sometimes to January of the next year. The month with the highest discharge is November. The dry season lasts for 8 months, when the discharge makes up only 30% of the total annual discharge. April is the month with the lowest discharge. Flow in different months are uneven, the difference between the highest monthly discharge and the lowest monthly discharge is very big. Flow and floods 62. Flow in the flood season: The flood season lasts for 3 months, from October to December, and is not stable. The month with the highest discharge is November. The runoff in the flood season makes up 30% of the total annual runoff. Apart from the main flood season, there are May rain-floods in May and June, and early floods from August to early October and late floods from December to mid January of the next year. 63. Flow in the dry season: In the dry season, the flow is small, the river flow is mainly supplied by groundwater sources. The dry season starts from January to August, with a total runoff of only 30-35% of the annual runoff. There are two dry period in the year, the first begins in April with an average discharge of 50.3 m3/s, and the second begins in July or August with the average discharge in August being about 61 m3/s. Salinity intrusion 64. In dry season months, the flow in the rivers is often small, which enables salinity intrusion to increase. Based on the variation of the river flow, salinity intrusion is also divided into 3 periods: Early dry season: January, February: Salt water intrudes river mouths and salinity tends to increase; Mid. dry season: often from March – August, the salinity intrusion possibility is the highest. Influences from May rain-floods forms two maximum points and one minimum point of the salinity intrusion, the strongest salinity intrusion occurs in May, July, August, with the highest salinity in July. Late dry season: the salinity in the rivers reduces quickly in the second half of September.

A3.7.2. Ecological features and cultural sites 65. Tra Khuc river upstream’s ecosystem is characterized by the tropical closed forest ecosystem. There is no Conservation area approved by The Government in the Basin. It indicates the conservation value and environmental assets in the basin is very low. 66. Basin forest cover rate is estimated 46% which is at medium level, compared to other basins. The rate indicates the important role of forest cover to the sustainable development of the river basin. Basin native forest rate is high 63.8% which indicates moderate forest quality and good catchment processes for runoff and water quality. In general, native forest area of the Basin is less than other South Central coastal basins; mainly of medium and poor forests. 67. There is one Historical/Cultural Sites approved by The Government in the Basin. Heritage Index of Vu Gia-Thu Bon basin is low-medium.

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Table A3.6: Ecological features of Tra Khuc, Ve, and Tra Bong river basin Total area: 5,200 km2 of which 5,200 km2 are located in Vietnam Environmental health: Biodiversity andecosystems Characteristics Included: terrestrial and aquatic and coastal ecosystems  Tra Khuc river upstream’s ecosystem is characterized by the tropical closed forest ecosystem  Ecosystem of Vu Gia-Thu Bon river’s downstream is coastal ecosystem. Conservation  There is no Conservation area approved by The Government in the Basin. areas  It indicates the conservation value and environmental assets in the basin is very low Historical/  There is one Historical/Cultural Sites approved by The Government in the Basin that Cultural Site is Cao Muon/Ba to.  Cao Muon Cultural and Historical Site is located in Ba Vinh, Ba Dinh, Ba Dien, Ba Chua and Ba Cung communes, Ba To district. The site is centered on Mount Cao Muon, an 829 m high mountain, situated north-west of Ba To town. Streams originating in the east of the site flow into the Ve river, streams originating in the north flow into the Ne river, streams originating in the west flow into the Lo river and streams originating in the south flow into the Tra No river. The latter three rivers feed the Ve river, which flows north through Quang Ngai province to meet the East Sea south of Quang Ngai town.  Heritage Index of Vu Gia-Thu Bon basin is low-medium (1), compared to other basins. Major water There is no major water related environmental assets related environmental assets Physical  Forest cover: 48% condition  Agricultural cover: 22% land use  Resident cover 2% proportions  Specific use 3%  Other use 25% Vegetation cover  Vegetation Index of Tra Khuc River Basin occupies 2.04% of total national forest area, lower than other basins. This basin take a less important role to meeting the national forest target  Basin forest cover rate is estimated 46% which is at medium level, compared to other basins. The rate indicates the important role of forest cover to the sustainable development of the river basin  Basin native forest rate is high 63.8% which indicates moderate forest quality and good catchment processes for runoff and water quality. In general, native forest area of the Basin is less than other South Central coastal basins; mainly of medium and poor forests

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A3.7.3. Water quality 68. The surface water quality in Tra Khuc – Ve – Tra Bong river basin is considered to be quite good (BOD, COD, DO values are generally good). In the period 2005-2009, the BOD value only exceeded the permissible limit once in 2006 in Tra Cau river in the My A sea mouth section (63mg/l), the COD exceeded the limit twice in 2006 in the upstream of Tra Cau river (27mg/l) and in My A sea mouth (181mg/l). 69. In general, surface water quality in the rivers varies differently. In Tra Cau river, according to monitoring results, water in the sea mouth section has the lowest quality (BOD and COD values in this area are 4 to 7 times higher than those monitored in the upstream and at Tra Cau river bridge). In Ve river, monitoring results show that pollution levels in the upstream and sea mouth sections are quite similar (BOD value exceeds the permissible limit by 1.2 to 2 times). A3.7.4. Socio-economic conditions

Economic conditions 70. The economic structure is: agriculture 34%, industry 27% and service 36%. The average GDP growth rate for the last 5 years is 10.8%. Agriculture: basically fulfills the demand for food of the locality but the growth rate is not high. Industry: focuses on several industrial establishments of small and medium scale. Dung Quat Industrial Zone is under construction and of great development potential. Social conditions 71. Population: Population scale: 1,297.5 thousand people, accounting for 1.54% of the national population. The average population density of the basin is 249 people/km2. The population is unevenly allocated, mainly gathering in cities and the delta. The average population growth rate of the basin is 1.48%. 72. Ethnicity: Ethnic minorities make up 32.62%, mainly concentrating in remote communes of Quang Ngai province and KonPlong district of Kon Tum province. 73. Employment: Employment in the agriculture sector accounts for 60.77%, industry: 12.45% and service 26.78%. It can be seen that the basin’s industry is underdeveloped while service is more developed. 74. Poverty rate: The average poverty rate in the basin is 66.8%, the highest compared to the other 15 basins. Poor people gather mostly in mountainous districts: Son Tay and Tay Tra with nearly 100% is poor households, then comes Tra Bong, KonPlong, and Son Ha with approximately 90% poor households.

A3.8. Kone River Basin (Binh Dinh) 75. Kone river basin (including the Ha Thanh and La Tinh river basin) has an area of 3,640 km2, located entirely within Vietnam territory and in the territory of Binh Dinh province. Kone River originates from the Truong Son mountain, about 160 km of main stream flows Southeast through the mountains, then moves East crossing the plains and pours into the sea. The basin’s terrain is relatively complex, lower from West to East. It can be divided into mountain area, midland, coastal plain and coastal dune. Presently, forest cover is only about over 40%, leading to the rivers causing floods each year and severe sedimentation. The map of Kone – Ha Thanh river basin is presented in Figure A2.8 (Annex 2). 76. The average annual rainfall is 1,700 – 1,800 mm. The rainy season, from August to December, concentrates from 70 - 80% of the yearly rainfall. Since the rainy season coincides with stormy season, flood often occurs. Prolonged dry season causes drought in many areas, the average humidity is 75%.

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77. May-rain flood usually occurs in May and June; early flood in the August and September; floods in high season in October and November and late flood in December. 78. Kone river basin’s ecosystem included: terrestrial and aquatic and wetland/mangrove ecosystems. Lower montane evergreen forest is presented for forest ecosystem of Kone-Ha Thanh upstream; Ecosystem of Vu Gia-Thu Bon river’s downstream is ecosystem like coral reefs, seagrass beds and coastal lagoons. There is one Conservation are that approved by The Government in the Basin, that is Kon Cha Rang Nature Reserve (15,900 ha). Conversation area index is estimated 4.37% is low-medium level, compared to other basins. The index indicates the conservation value and environmental assets in the basin is low-medium level. 79. There is only one Historical/Cultural Sites approved by The Government in the Basin, that is Quang Trung Museum. Invaluable cutural heritages of Tay Son Period with architectural set of Tay Son Temple and museum and martial arts house.

A3.9 Dinh river basin (Ninh Thuan) 80. Dinh river basins (also called Cai river - Phan Rang) covers almost Ninh Thuan province. The river originates from the Eastern slope of Gia Rich mountain bordering with Lam Dong province. The river flows Northsouth and pours into the Eastern Sea through the Gulf of Phan Rang. The length of the main stream is about 120 km. Total Cai river basin area is 3043 km2, in which, 2488 km2 of Ninh Thuan, 336 km2 of Khanh Hoa, 172 km2 of Lam Dong and 47 km2 of Binh Thuan. The map of Dinh river basin is presented in Figure A2.9 (Annex 2). 81. Due to the terrain of the upstream surrounded by high mountains, the basin’s annual rainfall is very large, from 1000 - 2000 mm. The basin has a tropical monsoon climate, with two obvious rainy and dry seasons. Rainy season is from July to November, dry season from December to June of the following year. Rainfall tends to gradually increase from the plains to the mountainous area. The average rainfall in many years in the coastal area is about 600 mm, in Phan Rang it is 712 mm, and Tan My 1,071 mm. In the high mountainous upstream part, rainfall may reach above 2000 mm.