Runoff and water quality of bui river at headwater catchment in luong son district, hoa binh province

MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM FORESTRY UNIVERSITY STUDENT THESIS RUNOFF AND WATER QUALITY OF BUI RIVER AT HEADWATER CATCHMENT IN LUONG SON DISTRICT, HOA BINH PROVINCE Major: Natural Resources Management Code: D850101 Faculty: Forest Resources and Environmental Management Student: Dương Tuấn Anh Student ID:1153092241 Class: K56 Natural Resources Management Course: 2011 - 2015 Advanced Education Program Developed in collaboration with Colorado State University, USA Supervisor: Dr Bùi Xuân Dũng Ha Noi, October/2015 ACKNOWLEDGEMENT I would like to express my sincere gratitude to Dr Dung and Prof: Lee Mac Donald providing continuous encouragement and enthusiastic support during the research work in I greatly appreciated the help provided for by the Lam Son hydrometeorology station provided for me data, laboratory of Vietnam Forestry University and Institute of Chemistry in Vietnam Academy of Science and Technology helped me to analysis water sample, and would especially like to thank Mss Huyen, Mss Xuan who helped me directly TABLE CONTENT ACKNOWLEDGEMENT TABLE CONTENT LIST OF TABLE LIST OF FIGURES ASBTRACT I INTRODUCTION 1.1 Introduction 1.2 Overview of the previous research issues .3 II OBJECTIVES III STUDY SITE AND METHODS 3.1 Study site 3.2 Methods 3.2.1 Identified the boundary of headwater catchment of Bui River 3.2.2 Runoff measurement 3.2.3 Rainfall measurement 10 3.2.4 Water quality measurement 11 IV RESULTS AND DISCUSTION 21 4.1 Parameter characteristics of Bui River’s headwater catchment 21 4.2 Flow regime characteristics of Bui River at headwater catchment 23 4.3 Water quality of Bui River 28 V CONCLUSION 34 REFERENCES 35 LIST OF TABLE Table Climate indicators at Lam Son commune Luong Son district, Hoa Binh province Table Parameter characteristics of headwater catchment of Bui River 22 LIST OF FIGURES Figure Location of study site at Lam Son commune, Luong Son district, Hoa Binh province Figure Flow chart of identify catchment boundary Figure Illustration graph for discharge measurement Figure Vietnamese rain gage measurement 11 Figure Boundary of Bui River’s headwater catchment 21 Figure Rainfall and discharge of Bui River from 2004-2014 24 Figure Relationship between monthly runoff and monthly rainfall 25 Figure Relationship between monthly runoff and monthly rainfall (a) Rainy season; (b) Dry season) 26 Figure Flow duration curves of Bui River 27 Figure 10 pH and TSS indicators of Bui River’s water samples 28 Figure 11 The relationship between TSS and discharge 29 Figure 12 DO indicator of Bui River’s water samples 30 Figure 13 COD and BOD indicators of Bui River’ water samples 31 Figure 14 Nitrate and Phosphate indicators 32 Figure 15 Total Coliform indicator of water sample 33 ASBTRACT To evaluate runoff generation and water quality at Bui River’s headwater catchment, I conducted field monitoring at Lam Son hydrometeorology station and examined eight water quality indicators (TSS, pH, DO, BOD, COD, Nitrate, Phosphate, and Coliform) Runoff generation was measured from 2004- 2014 by Lam Son hydrometeorology and before, after three storm events in August, 2015 Water quality was measured before and after storm events Base on hydrograph analysis, in Bui River’s headwater catchment, the relationship between monthly runoff and monthly rainfall was showed by equation y=0.574x + 29.621 R2= 0.5204 Flooding season’s flow ranges from 40% to 65% time of year, it is equivalents to 146 to 219 days of year with total runoff is from 623mm to 1991mm; it occupies 72% to 92% total annual runoff Total time of dry season’s flow (low flow) accounts for 128 to 219 days of year, total runoff from 124mm to 514mm The peak of flow of is also differences between years; highest daily peak flow is 152.5mm and lowest is 37.7mm Seven indicators of water quality (pH, TSS, DO, COD, BOD, NO3-, and Coliform) are satisfies with B1 Vietnam surface water quality standard (QCVN: 08:2008/BTNMT), just PO4- was excessed that standard But overall, the water quality of Bui River at headwater catchment is good for aquatic life, aquaculture, transport I INTRODUCTION 1.1 Introduction Vietnam has 2360 rivers totaling to more than 10 km and it would appear that this should provide copious supply of water to the nation (http://thewaterproject.org/water-incrisis-vietnam) However, due to the lack of physical infrastructure and financial capacity there is low utilization of the supply along with an uneven distribution of rain fall resulting in water shortages throughout the country Although Vietnam has improved its water supply situation in the past few decades, many rural parts of the country who are often the poorest communities, have not seen significant improvement It is reported that only 39% of the rural population has access to safe water and sanitation Nowadays in Vietnam both of quantity and quality of surface water are decrease even the government has many solutions to improve it The expedition of industrial zones and urbanization were causes of narrowed river and diversion Decline of forest in upland area combines with climate changes leads to flood in raining season and drought in dry seasons The Ministry of Natural Resources and Environment state that almost 80% of the diseases in Vietnam are caused by polluted water There are many cases of cholera, typhoid, dysentery and malaria each year in the country The rural population has moved from using surface water from shallow dug wells to groundwater pumped from private tube wells because of surface water polluted In the Northern region of Vietnam around Hanoi, there are evidences of arsenic contamination in the drinking water (water in crisisViet Nam Sahisna Suwal) About million people living in this area have a severe risk of arsenic poisoning and since elevated levels of arsenic can cause cancer, neurological and skin problems, this is a serious issue Untreated waste water or treated ineffectively in industrial zones and domestic were released directly into streams, rivers and lakes and popularity of using pesticides, herbicides, chemical fertilizers in agriculture are the causes of surface water polluted The geography and topography of Vietnam also makes the country susceptible to natural hazards such as typhoons, storms, floods and drought This then leads to a multitude of problems such as water pollution and waterborne diseases along with an impact on agricultural lands and livestock Both the environmental pollution in these river basins and natural disasters affects the nation's public health On valleys, streams became headwater of Bui River (Hoang Dinh Luu., 2014) Bui River plays an important role in provided water for domestic uses, agricultures and produce products of 5000 people at Lam Son commune The area of headwater catchment of Bui River is about 30km2 with 70% concentrate in rainy season that lead to flash floods The data of discharge and rainfall at headwater catchment of Bui River is monitored by Lam Son hydrometeorology station for many years However, it has not been used much for study to assess Bui River flow regime Water quantity and quality of Bui River at headwater catchment is directly affected by land use changes (especially Phoenix golf course was constructed in 2004 with area is 311.7ha), domestic waste and other sources from agriculture, grazing, construction, tourism… To assess water supply possibility in dry season, flooding probability in rainy season and water quality of Bui River at headwater, I focus on the research: “Runoff and water quality of Bui River at headwater catchment in Luong Son district, Hoa Binh province” 1.2 Overview of the previous research issues Runoff generation and water quality have been researched for many years in hydrology which was born in many years ago Understanding a discharge hydrograph is one of the most important areas in catchment hydrology because it is essential for flood prediction, water resources management, and chemical and ecological material transport Various processes such as saturated and unsaturated water flow in the soil layer [e.g., Tani, 2008], preferential flow [e.g., Tsuboyama et al., 1994], and Spatial and Temporal Controls on Soil Moisture and Stream flow Generation [e.g., C Jason Williams., 2005] have been examined as dominant processes in controlling discharge There are many factors effect to hydrology of headwater catchment: mobilization of pre-event soil water may dominate peak storm flow in steep forested headwater catchments (David E Bazemore et al., 1994) and pipe flow and bedrock groundwater play important roles in storm runoff generation (Taro Uchida et al., 2002; Sho Iwagami et al., 2009) besides that climate changes also strongly influents to precipitation, evapotranspiration… which are directly effect to runoff generation of headwater catchments (Zhaofei Liu et al., 2009; Z.X Xu et al., 2008) Headwater contributes to condition flows of downstream water body and directly influences to water quality of downstream Any change of water quality at headwater can affect to water of downstream Land use influences to water quality dependent and varies in time and space (Oliver Buck et al., 2004) Phosphorus (P) and suspended sediment (SS) can impair surface water quality (R W MCDowell et al., 2009) and nonpoint source nitrogen (N) pollution is a leading contributor to water quality impairments (Sujay A Kaushal et al., 2011) Increasing of riparian cover near streams can reduce amount of phosphorus, suspended sediment and nitrogen flow to stream (Lewis L Osborne et al., 2006) It is rarely studies on Bui River One of them focus on evaluating factors affected to water quality of Bui River ( Hoang Dinh Luu., 2012) but this study was not showed clearly the characteristics of Bui River flow regime So, study on runoff generation and water quality of Bui River is necessary II OBJECTIVES This study focus on three main objectives; (1) Identify Bui River headwater catchment (2) Evaluating runoff characteristics of Bui River’s headwater catchment (3) Examining water quality of Bui River III STUDY SITE AND METHODS 3.1 Study site Figure Location of study site at Lam Son commune, Luong Son district, Hoa Binh province Table Climate indicators at Lam Son commune Luong Son district, Hoa Binh province Month Temperature (0C) Precipitation (mm) Moisture (%) 16 15 84 17.3 21 85 20.6 28 85 24.3 96 84 27 234 82 28.1 259 83 28.2 331 84 27.6 342 86 26.4 343 86 10 23.9 178 82 11 20.6 54 82 12 17.4 12 83 Mean 23.1 1913 84 (Source: Climate software – Institute for forest ecology and environment- Viet nam Forestry University 2014) Lam Son is one north- west commune of Luong Son dictrict, Hoa Binh province It is about 46km far from Ha Noi The terrain of Lam Son commune is mountainous and limestone alternating with absolute elevation is 500m and relative elevation is 130m (sources: Institute for Forest Ecology & Environment of VFU) Geographical coordinates: 200 45’ – 210 01’ in the North 1050 24’ – 1050 39’ in the East The topography of Lam Son consists mainly of limestone alternating with mountains Absolute elevation is 500 m above sea level and relative elevation is 126m The climate of IV RESULTS AND DISCUSTION 4.1 Parameter characteristics of Bui River’s headwater catchment Figure Boundary of Bui River’s headwater catchment 21 Table Parameter characteristics of headwater catchment of Bui River No Characteristics of catchment Value Catchment area 30.7 km2 Catchment perimeter 27.8 km Shape index (Kc) 1.4 Drainage density (Dd) 0.91 km/km2 Length of catchment 8.7 km Highest slope 62o Lowest slope 0o Average slope 9o Highest elevation 770m 10 Lowest elevation 30m 11 Average elevation 206m Bui River headwater catchment was form in an area which has average elevation is 206m (highest elevation: 770m and lowest elevation: 30m) The highest slope of catchment is 62o, lowest slope is 0o and the average slope is 9o This is a medium catchment with the area is 30.7km2 and 27.8km of perimeter Length of catchment is 8.7km Shape index (Kc) of catchment is 1.4 and drainage density (Dd) is 0.91km/km2 show that stream density is quite dense Almost streams in catchment flow with directions: Northwest- Southeast and North- South, it favors with characteristics of rivers, streams of northern mountainous area in Vietnam 22 4.2 Flow regime characteristics of Bui River at headwater catchment The rainy season begins from April to October; it takes about 82% (2008) to 97% (2013) of total annual rainfall Dry season begins from November to March of next year In In period of time from 2004 to 2014, the mean annual rainfall is 1764.5 mm, the highest rainfall is 2211.7 mm in 2011 and lowest is 1308.8 mm in 2010 (Fig 6.) So, the rain regime at Lam Son is complied with the rules of rainfall variation in northern of Vietnam which is affected by monsoon Depends on variation of runoff, flooding season in Lam Son begins from May to October with the total runoff range 623mm to 1991mm, it is account for 72% to 92% total annual runoff Despite that the flooding season can come sooner or later however July, August and September are usually three months have highest total runoff occupies 43%66%total annual runoff In flooding season, it provides 19.12 million cubic meter water to 61.13 million cubic meter water for downstream Dry season begins from November to April next year with total runoff range from 124mm to 514mm; it occupies 8% to 28% of total annual runoff In dry season, headwater of Bui River provides 3.81 million cubic meters to 15.79 million cubic meters of water for downstream It is meaningful for water supply for people’s living activities and production activities in downstream 23 Figure Rainfall and discharge of Bui River from 2004-2014 24 Monthly runoff (mm month-1) 600 y = 0.574x + 29.621 R² = 0.5204, P