Evaluation of surface water quality in Bac Kan pro- 123docz.net

To assess the current situation and surface water quality in Bac Kan province, the monitoring parameters after observation were compared with QCVN 08-MT: 2015

Quality Index (WQI) were caculated follow the Decision No. 879 / QD-TCMT dated July 1, 2011 issued by the Vietnam Environment Administration Handbook for calculating water quality indicators.

* Evaluation of surface water quality in Bac Kan province (stage 1) - Cau River Basin:

Cau River Basin is one of the main river basins in the province. In 2017, 17 points will be observed in the basin of the bridge, include: NMCĐ-6, NMBT-1, NMBT-2, NMBT-3, NMBT-4, NMTX-1, NMTX-4, NMTX-5, NMTX-6, NMTX-7, NMTX-8, NMCM-1, NMCM-2, NMCM-3, NMCM-4, NMCM-5, and NMCM-6. The results show that the surface water of Cau river basin is relatively good. Most monitoring sites have the concentration values within the permission standard which regulates in QCVN 08-MT:

2015/BTNMT (column B1). Only 3 out of 17 sites were contaminated by BOD5 and COD:

+ The position of Nong Thuong Stream passes through Quang Son residential area (NMTX5) has the value of BOD5 exceeds QCVN (column B1) is 1.2 times; COD exceeds standard (column B1) is 1.13 times.

+ The location of Pa Danh stream (NMTX6) has the BOD5 parameter exceeding the standard (column B1) 1.09 times.

+ Location of stream running through Phung Chi Kien and Duc Xuan wards (NMTX7) BOD5 exceeds QCVN (column B1) is 1.28 times

The average concentration of BOD5 of all monitoring points on the first stage in Cau river was 10.08 mg/l. Average COD concentration was 17.84 mg/l. The average TSS was 21.52 mg/l.

Based on the results of the WQI calculation, the average WQI of the monitoring

but needs to be treated suitability).

Nang River Basin:

In 2017, seven sites werw monitored in the Nang River basin: NMPN1, NMPN2, NMPN3, NMNS2, NMBB1, NMBB2, and NMBB7. According to the monitoring results of the Nang River surface water quality in 2017, the river water quality is still good. Most of the parameters are within the permission standard regulated by QCVN 08-MT: 2015 / BTNMT (B1).

The average BOD5 value of surface water monitoring sites in Nang River in 2017 was 9.54 mg / l. The average COD was 18.19 mg/l. The average TSS was 33 mg / l.

Surface water monitoring in the Nang River basin is higher than the standard is NMPN2 (stream water after flowing through Boc Bo commune), exceeding the national standard QCVN 08-MT: 2015/BTNMT (column B1) is 1.14 times. Due to observation time of stage 1 coincide with the time of spring farming land of the people, the fields along the stream people are plowing, harrowing, the amount of water to chase the streams many. In addition, the washing of agricultural machinery on the stream after plowing also increased the amount of TSS of the spring water.

The average WQI of the monitoring sites in the first river basin is 86.04 (used for domestic water supply but appropriate treatment is required).

- Ba Be Lake Basin:

The Ba Be Lake Basin includes the lake monitoring sites and tributaries flowing into the lake.The environmental monitoring program of Bac Kan province in 2017 have 5 monitoring points in Ba Be lake basin, including the locations of NMC3, NMBB5, NMBB6, NMBB3, and NMBB4. Results of monitoring parameters show that surface

parameters are much lower than allowed standard by QCVN.

The average BOD5 value of the first stage in Ba Be Lake basin was 5.42 mg / l;

Average COD value was 8.78 mg / l; Average TSS was 9.8 mg / l.

The average WQI of Ba Be Lake basin was 96.6 (that mean water is well used for domestic water supply).

- Bac Giang river basin:

Bac Giang river basin in Bac Kan province in 2017 is monitored at 8 locations:

NMNS1, NMNS4, NMNR1, NMNR2, NMNR3, NMNR4, NMNR5, and NMNR6.

Water quality in Bac Giang province is good. The values of monitoring parameters at all monitoring sites in the Bac Giang river basin in 2017 are within the permitted limitation of QCVN (column B1).

The average BOD5 value of the first stage was 10.33 mg/l. Average COD was 18.6 mg/l. Average TSS of the first stage was 27.63 mg/l.

The average water quality index of the monitoring sites in the first stage of Bac Giang river basin is 87.73 (It can be used for domestic water supply but requires appropriate treatment measures)

0 5 10 15 20 25

BOD concetration of Observation 1

National Technical Standard 08:2015/BTNMT (column B1)

Figure 3. Chart of COD levels in surface water stage 1 in 2017

Figure 4. Chart of TSS concentration in surface water stage 1 in 2017

0 10 20 30 40 50 60

TSS concetration of Observation 1

National Technical Standard 08:2015/BTNMT (column B1)

0 10 20 30 40

COD concetration of Observation 1

National Technical Standard 08:2015/BTNMT (column B1)

Table 5. Water Quality Index (WQI) at Surface Water Surface Monitoring in Bac Kan province, phase 1 in 2017 (Report on environmental monitoring results of Bac Kan province-2017)

TT Basins of river and lakes

Sample

symbol Location of monitoring QI value Color Evaluation of water quality

Cau River Basin

NMCĐ-6

Cau river water in Dong Vien commune (Khau Chu suspension bridge)

94,03 Blue

It is good to use for water supply purposes

2 NMBT-1 Na Cu stream (Cam Giang

commune) 94,52 Blue It is good to use for water supply purposes

3 NMBT-2 Phu Thong stream (at Suoi

To bridge) 95,8 Blue It is good to use for water supply purposes

4 NMBT-3 Na Cu stream in Nguyen

Phuc commune 95,29 Blue It is good to use for water supply purposes

5 NMBT-4 Sy Binh stream in My

Thanh commune 97,23 Blue It is good to use for water supply purposes

6 NMTX-1 Cau river water (Duong

Quang bridge) 92,22 Blue It is good to use for water supply purposes

7 NMTX-4 Nam Cat stream water 97,04 Blue It is good to use for water supply purposes

8 NMTX-5

Nong Thuong Stream flows through Quang Son residential area, Doi Ky

78,69 Green It is used for water supply purposes but requires appropriate treatment measures.

9 NMTX-6 Pa Danh stream 83,11 Green It is used for water supply purposes but requires

appropriate treatment measures.

10 NMTX-7

The stream flows through Phung Chi Kien and Duc Xuan wards

79,95 Green

It is used for water supply purposes but requires appropriate treatment measures.

TT Basins of river and lakes

Sample

symbol Location of monitoring QI value Color Evaluation of water quality

12 NMCM-1

Cau river water in Nong Ha (after waste water discharge of B & H paper factory)

82,06 Green

It is used for water supply purposes but requires appropriate treatment measures.

13 NMCM-2 Cau river water in Thanh

Binh commune 89,77 Green It is used for water supply purposes but requires appropriate treatment measures.

14 NMCM-3 Cau river water (at Yen

Dinh bridge) 91,68 Green It is used for water supply purposes but requires appropriate treatment measures.

15 NMCM-4 Cho Chu Spring Water (O

Ga Bridge) 87,69 Green It is used for water supply purposes but requires appropriate treatment measures.

16 NMCM-5 Cau river water at Tham

temple 87,27 Green It is used for water supply purposes but requires appropriate treatment measures.

17 NMCM-6 Quan water springs at

bridge 62 82,29 Green It is used for water supply purposes but requires appropriate treatment measures.

The average value 89,64 Green It is used for water supply purposes but requires appropriate treatment measures.

The Nang River Basin

NMPN-1

Stream water flows into Boc Bo commune (at overflow bridge)

88,58 Green

It is used for water supply purposes but requires appropriate treatment measures.

19 NMPN-2 Stream water after flowing

through Boc Bo commune 77,22 Green It is used for water supply purposes but requires appropriate treatment measures.

20 NMPN-3

Nang River water in Boc Bo commune (Na Nghe village)

91,05 Green

It is used for water supply purposes but requires appropriate treatment measures.

21 NMNS-2 Na Phac stream (at Na

Phac bridge) 91,37 Green It is used for water supply purposes but requires appropriate treatment measures.

Water of Nang river at It is used for water supply purposes but requires

TT Basins of river and lakes

Sample

symbol Location of monitoring QI value Color Evaluation of water quality

23 NMBB-2 Water of Nang River at

Buoc Lom (wharf) 81,06 Green It is used for water supply purposes but requires appropriate treatment measures.

24 NMBB-7

Water of Ha Hieu River at Pac Cham suspension bridge in Bach Trach commune

93,22 Blue It is good for use for water supply purposes

The average value 86,04 Green

It is used for water supply purposes but requires appropriate treatment measures

Basin of Ba Be Lake

NMCĐ-3

Quang Bach - Nam Cuong Stream (Nam Cuong commune)

92,66 Green

It is used for water supply purposes but requires appropriate treatment measures

26 NMBB-5

Cho Leng spring water (Pac Ngoi suspension bridge)

96,15 Blue

It is good for use for water supply purposes

27 NMBB-6 Ta Han stream (at Coc Toc

village) 96,97 Blue It is good for use for water supply purposes

28 NMBB-3 Ba Be Lake Water (Lake

1) 99,37 Blue It is good for use for water supply purposes

29 NMBB-4 Ba Be Lake water (Lake 3) 97,88 Blue It is good for use for water supply purposes The average value 96,6 Blue

It is good for use for water supply purposes

TT Basins of river and lakes

Sample

symbol Location of monitoring QI value Color Evaluation of water quality

31 NMCĐ-2 Pho Day River water

(BinhTrung commune)) 90,9 Blue It is good for use for water supply purposes

32 NMCĐ-5

Water of Pho Day River in Bang Lang commune (Tum To bridge)

92,68 Blue

It is good for use for water supply purposes

33 NNCĐ-7

Water of Pho Day river in Yen Nhuan commune (second branch)

95,35 Blue

It is good for use for water supply purposes

The average value 93,21 Blue It is good for use for water supply purposes 34

Bac Giang River

NMNS-1 Van Tung stream water

(Van Tung bridge) 93,14 Blue It is good for use for water supply purposes

35 NMNS-4 Huan Mang Stream (Ban

Giang Bridge) 88,8 Green It is used for water supply purposes but requires appropriate treatment measures.

36 NMNR-1 Bac Giang river water

(Luong Thuong commune) 80,58 Green It is used for water supply purposes but requires appropriate treatment measures.

37 NMNR-2

Bac Giang river water (Tan An suspension bridge)

82,26 Green

It is used for water supply purposes but requires appropriate treatment measures.

38 NMNR-3 Bac Giang river water (Pac

Cap I dam) 80,09 Green It is used for water supply purposes but requires appropriate treatment measures.

39 NMNR-4 Water of Na Ri river (Pac

Cap II dam) 93,54 Blue It is good for use for water supply purposes

40 NMNR-5 Bac Giang river water (Hat

Deng bridge) 90,12 Green It is used for water supply purposes but requires appropriate treatment measures.

41 NMNR-6 Water of Na Ri River (Hao

Nghia Bridge) 93,34 Blue It is good for use for water supply purposes It is used for water supply purposes but requires

* Note: The WQI value corresponds to the water quality assessment as follows:

WQI value Color Water quality assessment

91 - 100 Blue It is well used for water supply purposes

76 - 90 green

It is used for water supply purposes but requires appropriate treatment measures.

51 - 75 yellow Used for irrigation and other similar purposes.

26 - 50 Orange Used for navigation and other similar purposes.

0 - 25 red Heavy polluted water, need treatment measures in the future.

* Evaluation of surface water quality in Bac Kan province (stage 2) - Cau River Basin:

Analytical results show that the surface water of the Cau River basin phase 2 in 2017 is relatively good. Most monitoring indicators at monitoring sites have concentration values within the permission standard in QCVN 08-MT: 2015/BTNMT (column B1). Only the Bac Kan City’s wastewater source is polluted by the BOD5 and COD parameter.

+ The position of Nong Thuong stream flows through Quang Son residential area, Hoa Ky (NMTX5) has BOD5 value exceeds QCVN (column B1) 1.01 times; The COD exceeds the norm (column B1) 1.05 times.

+ Location of stream running through Phung Chi Kien and Duc Xuan wards (NMTX7) BOD5 exceeds QCVN (column B1) is 1.23 times; COD exceeds 1.01 times.

The average BOD5 concentration of the monitoring points in stage 2 in Cau river was 9.0 mg / l.

Comparison of BOD5 monitoring results between 2 stages, the average of BOD5 in stage 2 was reduced by 1.08 mg/l. Average COD of stage 2 was 16.34 mg/l.

Comparing the average COD between the two observation stages, the stage 2 was reduced by 1.5 mg/l.

The average TSS value of the monitoring points of Cau river in 2017 was 26.76 mg/l. Comparison between these two observation stage, the average TSS value of stage 2 is 5.24 mg/l higher than the average TSS of the first stage.

Remaining parameters are pH, As, Cd, Cr6 +, Zn, Fe, Cu, Hg, Pb, NH4 +, NO3-, NO2-, CN-, PO43-, grease, phenol and coliform were much lower than the permitted standard regulated by QCVN 08-MT: 2015/BTNMT.

Based on the results of the WQI calculation, the average WQI of the monitoring points of stage 2 of Cau river was 88.6 (used for domestic water supply but needs to be treated). Compared to the average WQI value of stage 1, the WQI value of stage 2 were lower by 1.04 showed. That means the surface water quality at the stage 1 was better than stage 2.

- Nang River Basin:

In 2017, seven sites will be monitored in the Nang River basin: NMPN1, NMPN2, NMPN3, NMNS2, NMBB1, NMBB2, NMBB7. According to the monitoring results of surface water quality the Nang River in 2017, the river water quality is still good. Monitoring parameters are within the allowable standard of the 08-MT standard: 2015 / BTNMT (column B1).

The average BOD5 of surface monitoring points of stage 2 in 2017 was 9.13

mg / l. Compared to the first stage, the second stage was reduced by 0.41 mg / l.

Average COD of stage 2 was 16.63 mg / l. Compared with the stage 1 in 2017, the average COD value of stage 2 is less than that in stage 1 by 1.56 mg / l.

The average value of TSS in surface waters of the Nang River basin was 33.57 mg/l, compared to the average. is 0.57 mg/l. Compared with the same observation period in 2016, the TSS value in surface waters of the Nang River Basin increased by 2.41 mg/l.

The average WQI of the monitoring sites in the Nang River basin was 86.24.

Compared to the average WQI of stage 1, the average WQI value higher than that in stage 1 by 0.2; Water quality in the Nang river in stage 2 is better than that in stage 1.

- Ba Be Lake Basin:

The Ba Be Lake Basin includes the lake monitoring sites and tributaries flowing into the lake. The 2017 monitoring program in the basin of Ba Be lake have five monitoring sites, including the locations of NMC3, NMBB5, NMBB6, NMBB3, NMBB4. Results of monitoring parameters show that the water quality of surface water monitoring sites in Ba Be Lake basin is very good. All monitoring parameters are much lower than allowed standard regulated by QCVN.

The average BOD5 value of monitoring points in the Ba Be Lake basin was 4.9

mg/l. The average BOD5 value in stage 2 was lower that that in the first stage by 0.52 mg/l.

The average COD value of stage 2 was 8.9 mg/l, compared with the first stage;

the second stage was 0.12 mg/l higher than the first stage.

The mean TSS of the second stage was 13.2 mg/l, compared with the mean TSS of the first stage; the TSS value of the second one was 3.4 mg/l higher than that in the first stage.

The average WQI of Ba Be Lake basin was 95.09. Compared to the average WQI of the first stage, the second round was 1.51 times lower than the first stage; Water quality in the first stage of the reservoir is better than the second one.

- Bac Giang river basin:

The basin of Bac Giang river in 2017 is monitored at 8 locations: NMNS1, NMNS4, NMNR1, NMNR2, NMNR3, NMNR4, NMNR4, and NMNR5. Water quality in Bac Giang province is good. The values of monitoring parameters at all monitoring sites in the Bac Giang river basin in 2017 are within the permitted limits of QCVN (column B1).

The average BOD5 value of the second stage was 9.59 mg/l, compared with the first batch, the average BOD5 value of the second batch was reduced by 0.74 mg / l.

The average COD value was 18.15 mg/l, compared to the first one, the average COD of the second one was lower by 0.45 mg / l.

The mean TSS of the second stage was 31.5 mg/l. Compared with the first stage, stage 2 was 3.87 mg/l higher than stage 1.

The average water quality of the monitoring sites in the Bac Giang river basin phase 2 is 86.37; Compared to the first round, the WQI fell by 1.36 . The water quality of phase 2 is better than phase 1 in Bac Giang.

Figure 5. Chart of BOD5 concentration in surface water phase 1 compared with phase 2 in 2017

Figure 6. Chart of COD concentration in surface water phase 1 compared to phase 2 in 2017

0 5 10 15 20 25

BOD concetration of Observation 1 BOD concetration of Observation 2

National Technical Standard 08:2015/BTNMT (column B1)

0 10 20 30 40

COD concetration of Observation 1 COD concetration of Observation 2

National Technical Standard 08:2015/BTNMT (column B1)

Figure 7. Chart of TSS levels in surface water phase 1 compared to phase 2 in 2017

0 20 40 60

TSS concetration of Observation 1 TSS concetration of Observation 2

National Technical Standard 08:2015/BTNMT (column B1)

Table 6. Water Quality Index (WQI) at surface water surface monitoring in Bac Kan province, phase 2 in 2017 (Report on environmental monitoring results of Bac Kan province-2017)

STT Basin of rivers and lakes

Monitoring point code

Locations of monitoring

point WQI Expression Evaluation of water quality

Cau rive basin

NMCĐ-6 Water in Cau bridge in

Dong Vien commune 94,76 Blue Well used for water supply purposes

2 NMBT-1 Water in Na Cu stream (

Cam Giang commune) 90,05 Blue Well used for water supply purposes 3 NMBT-2 Water at Phu Thong stream 95,58 Blue Well used for water supply purposes

4 NMBT-3 Stream water in Na Cu,

Nguyen Phuc commune 93,1 Blue Well used for water supply purposes

5 NMBT-4 Stream water in My Binh,

My Thanh commune 97,99 Blue Well used for water supply purposes

6 NMTX-1 Cau River’s WaterNước

(Duong Quang bridge) 94,77 Blue Well used for water supply purposes

7 NMTX-4

Water in Nam Cat stream 97,96 Blue Well used for water supply purposes It is used for water supply purposes but

9 NMTX-6 Pa Danh Stream water 78,43 Green