Maximum water levels. Changes in th

Maximum water levels. Changes in the maximum water level are shown in Fig. 4. Before the impoundment at the TGR, the highest water level at Yichang, Zhicheng, and Shashi stations showed fuctuating but generally decreasing trends. Afer impoundment began, there was no signifcant trend, but the maximum water levels measured were lower than the pre-impoundment maxima. Before construction of the TGR, the maximum water levels at Luoshan Station and Hankou Station increased slightly, but there was no signifcant elevation change post-construction. A comparison between the water levels during the 2003–2016 period with the water levels corresponding to the same fow rates before construction of the TGR shows that post-construction water levels were all elevated, and the expected decline did not occur.Variation of water levels at the same discharge.