Three Gorges Bulletin in 2007

In 2006, the Three Gorges Project had steady progress with fulfillment of all major objectives in time. The comprehensive benefits of the project in such areas as flood control, power generation and navigation emerged in an all round way.

The Three Gorges reservoir area continued its rapid social and economic development in 2006. Local GDP grew by 13.1% compared with that of 2005 according to comparable price. The industrial structure of the reservoir area continued optimizing with steady growth of the output of each industry and rising living standard. Public health was basically good.

In 2006, the temperature of the Three Gorges reservoir area was abnormally higher than the historical average with evident less precipitation due to the impacts of global warming and abnormal atmospheric circulation. And Chongqing suffered the biggest drought one in 100 years. There was no large-scale serious storm and flood disaster all the year round.

In 2006, the total amount of fish fry of the "four major local fish species" of the Yangtze River had some rise, but still at low level. There was a reduction of the parent crabs and coilia mystus resources at the estuary at different degree with some increase of eel fry resource. The overall water quality of important fishery waters was good, basically meeting the requirements for fish reproduction.

In 2006, there was some decline of eco environmental pressure on farmland in the Three Gorges reservoir area. However, arable land area and total crop sown area continued going down. Agricultural production was still dominated by grain crops. Earthquake activity was similar to that of the last year with rise of micro quakes after impoundment but maintaining low intensity and normal level. The monitoring and early warning of geological disasters made some achievements with smooth progress in the three-stage prevention and control projects.

In 2006, total discharge of industrial wastewater of the Three Gorges reservoir area was 628 million tons and that of COD and ammonia nitrogen was 81,100 tons and 6400 tons respectively. Total discharge of urban sewage was 496 million tons and that of COD and ammonia nitrogen was 102,700 tons and 10,200 tons respectively. The amount of ship-oil wastewater was 470,800 tons, down by 5.2% than that of 2005, 97.1% of them under treatment. The amount of ship-born domestic sewage was about 3.32 million tons, clearly more than that of 2005.

In 2006, the overall environmental quality of both the construction areas and migrant resettlement areas of the Three Gorges Project was good. The water quality of mainstream of the Yangtze River of the Three Gorges reservoir area was dominated by Grade III and most waters of the tributaries met Grade IV national surface water quality standard, there was some degradation compared with that of 2005. Many water blooms occurred in the tributaries of the Yangtze River, showing the trend of river water blooms to lake water blooms.

The Three Gorges reservoir finished 135 m impoundment in 2003. It successfully realized 156 m impoundment in 2006. The reservoir had operated smoothly during the past 4-year impoundment. Meanwhile, monitoring results show overall good water quality in the reservoir. Based on the real conditions of the Three Gorges Project, the monitoring system has carried out regular and random monitoring on important eco environment factors and obtained a great deal of ecological and environmental data since 1996 when the "Ecological and Environmental Monitoring System for the Three Gorges Project of the Yangtze River" formally launched. The current Bulletin listed the monitoring results of major ecological and environmental indicators of the Three Gorges reservoir area in 2006 (after impoundment) and 2000 (before impoundment), indicating the change before and after the impoundment. It should be pointed out that to comprehensively identify the impacts of the Three Gorges Project on ecological environment and its change, we need long-term accumulation of data, systematic analysis and in-depth study.

Monitoring results of major ecological and environmental indicators of the Three Gorges

Indicators		Monitoring results in 2006						Monitoring results in 2000
1. Hydrologic indicators¹		Water table (m)	Flow (m³/s)	Flow speed (m/s)		SS (mg/L)		Water table (m)	Flow (m³/s)		Flow speed (m/s)		SS (mg/L)
(1) Mainstream inflow to the reservoir (Annual average)		163.42	9328	2.14		458.1		164.58	12809				368.2
(2) Mainstream of the reservoir area (Annual average)		141.31	8747	0.21		41.8		72.58	13120				423.0
(Low flow period)		138.12	3930	0.09		12.6		66.67	3970				72.2
(Normal flow period)		138.24	8400	0.19		31.4		67.68	5800				89.6
(High flow period)		135.40	11580	0.11		92.3		74.96	16500				773.0
(3) Mainstream outflow of the reservoir (Annual average)		64.69	8396	0.40		28.1		66.23	13936				441.0
2. Water quality²		Low flow period	Normal flow period	High flow period		Whole year		Low flow period	Normal flow period		High flow period		Whole year
(1) Mainstream inflow to the reservoir		Ⅲ	Ⅲ	Ⅲ		Ⅳ (Petro- leum)		Ⅱ	Ⅴ (TP)		Ⅲ		Ⅳ (TP)
(2) Mainstream of the reservoir area		Ⅲ	Ⅲ	Ⅲ		Ⅲ		Ⅱ	Ⅲ		Ⅱ		Ⅲ
(3) Mainstream outflow from the reservoir		Ⅲ	Ⅲ	Ⅲ		Ⅲ		Ⅱ	Ⅲ		Ⅱ		Ⅲ
Note: 1. Extreme summer drought (one in 100 years) occurred in areas like Sichuan and Chongqing in 2006. 2. Monitoring and assessment methods and standards are seen in relevant chapters and sections of the current Bulletin. 3. Thyromegaly rate was the sampling investigation results at Wanzhou monitoring site. 4. Data in the brackets is the distance between the monitoring site and the Yangtze River dam or estuary gate. 5. AH = artificial hour.
3. Groundwater indicators²		Confined ground- water table (m)	Phreatic surface (m)				Confined ground- water table (m)			Phreatic surface (m)
(1) Borehole A (1.5 km) ⁴		22.52	22.14				22.54			22.36
(2) Borehole B (3.0 km) ⁴		21.64	22.41				21.70			22.56
(3) Borehole C (5.0 km) ⁴		21.74	22.18				21.90			22.22
(4) Borehole D (8.5 km) ⁴		21.35	21.88				21.35			21.94
(5) Borehole E (13.0km) ⁴		21.99	22.02				21.86			21.87
4. Earthquakes²		0≤M_L≤1.9	2.0≤M_L≤2.9	3.0≤M_L≤3.9	M_L>3.9		0≤M_L≤1.9			2.0≤M_L≤2.9		3.0≤M_L≤3.9		M_L>3.9
Head to the middle parts of the reservoir area		958	57	4	0		113			27		1		1
5. Meteorological indicators²		Precipita- tion (mm)	Tempe- rature (℃)	Evapo- ration (mm)	Foggy days (d)		Precipi- tation (mm)			Tempe- rature (℃)		Evapo- ration (mm)		Foggy days (d)
Reservoir area (Annual average)		877.6	18.8	1428.5	24		1190			17.3		1269		28.5
6. Fish indicators		Amount of caught fish species	Amount of endemic species				Amount of caught fish species			Amount of endemic species
(1) Yichang Section (Spring)		16	4				46			6
(2) Yichang Section (Autumn)		38	5				25			6
7. Fishery indicators		Total catch (10⁴t)		Fish fry flow of the “four major local fish species” in May~June (10⁸ tails)			Total catch (10⁴t)					Fish fry flow of the “four major local fish species” in May~June (10⁸ tails)
(1) Reservoir & downstream waters		5.5		-			8.5					-
(2) Jianli section downstream the Dam		-		2.31			-					28.54
8. Health indicators²		Birth rate (‰)	Death rate (‰)				Birth rate (‰)			Death rate (‰)
(1) Life statistics		6.4	5.0				8.8			5.9
(2) Diseases		Total cases of infectious diseases	Total morbidi- ty rate of infect- ious diseases (/10⁵)	Thyro- megaly rate³(%)			Total cases of infect- ious diseases			Total morbidi- ty rate of infect- ious diseases (/10⁵)		Thyro- megaly rate³ (%)
(2) Diseases		3914	637.15	13.75			2238			429.37		15.75
(3) Biological media		Indoor mouse density (%)	Outdoor rat density (%)	Indoor mosquito density (/room· AH⁵)	Live- stock pen mosque- to density (/pen·AH⁵)		Indoor mouse density (%)			Outdoor rat density (%)		Indoor mosque- to density (/room· AH⁵)		Livestock pen mosquito density (/pen·AH⁵)
(3) Biological media		2.17	1.91	30.88	101.9		3.91			2.97		46.22		215.51
9. Salinity of the estuary water²		EC of the Yangtze River water (ms/cm)	Ground- water EC (ds/m)	Ground- water table (cm)			EC of the Yangtze River water (ms/cm)			Ground- water EC (ds/m)		Ground- water table (cm)
(1) Yinyang section (4 km) ⁴		32.82	2.74	74			30.59			3.22		98
(2) Daxing section (22km) ⁴		25.51	2.57	107			30.46			2.36		97
(3) Xinglongsha section (35km) ⁴		18.24	2.32	103			28.33			2.82		64
Environmental Quality of Construction Areas	10. Hydro- meteorology²	Flow (m³/s)	Sediment (kg/m³)	Precipi- tation (mm)	Tempe- rature (℃)		Flow (m³/s)			Sediment (kg/m³)		Precipi- tation (mm)		Tempera- ture (℃)
	(1) Huangling- miao Hydrologic station	9010	0.031				14500			0.840
	(2) Three Gorges Dam area			1045	17.7							1301		16.5
	11. Air quality²	NO₂ (mg/m³)	SO₂ (mg/m³)	TSP (mg/m³)	Primary pollutants		NO₂ (mg/m³)			SO₂ (mg/m³)		TSP (mg/m³)		Primary pollutants
	11. Air quality²	0.027	0.027	0.183	TSP		0.019			0.007		0.259		TSP
	12. Water quality²	The first quarter	The second quarter	The third quarter	The fourth quarter		The first quarter			The second quarter		The third quarter		The fourth quarter
	(1) Main- stream	Ⅰ	Ⅱ	Ⅱ	Ⅰ		Ⅱ			Ⅱ		Ⅴ (Perman-ganate index)		Ⅲ
	(2) Alongshore water	Ⅰ	Ⅱ	Ⅱ	Ⅰ		Ⅱ			Ⅴ (Perman- ganate index)		Ⅱ		Ⅱ
	13. Noise²	Daytime noise (dB)	Night noise (dB)	Boundary noise (dB)	Traffic noise (dB)		Daytime noise (dB)			Night noise (dB)		Bound- ary noise (dB)		Traffic noise (dB)
	13. Noise²	58.2	50.1	56.2	69.1		59.2			52.4		54.9		67.7