Abstract: In order to improve the ability of water environment pre-warning and emergency response on the Huaihe River basin, the Hydrology, Hydrodynamics, and Water Quality Model (DHQM) is developed for the Huaihe Middle River network. The Huaihe DHQM comprises three 1-D parts (Huaihe River stem, Shaying River, and Guohe River) and two 2-D parts (Lutaizi Reach and Bengbuzha Reach). The water quantity and quality series during 2004 and 2008 were used to calibrate and validate the model, respectively. A typical virtual accident scenario was assumed based on the pollution characteristics of the Huaihe River basin. The Huaihe DHQM was applied to analyze the effects of pollution mass on downstream across different combinations of regulation scheme and flow from the Huaihe River stem. After comparing the modeling results of different regulation schemes, the slow release of water from several installments under a low discharge was identified as the optimal emergency scheme that could secure the water quality of Bengbu and minimize the influence of pollution mass on downstream.