近年来，随着水利开发活动的增加和对水资源需求的增强，区域、流域的水资源和生态、环境状况发生了很大变化。随着人类对水利开发活动引起的环境问题的深入认识，使得环境影响评价工作从项目评价发展为规划层次的评价。2003年颁布的《中华人民共和国环境影响评价法》要求水利等10类专项规划要组织规划环境影响评价工作，规划环境影响评价是环境影响评价在规划层次的应用，是一种在规划层次及早协调环境与发展关系的决策手段，对单个项目的环境影响评价起指导和限定作用，是完善水利规划环境管理体系的重要部分。迄今为止，水利规划环境影响评价在我国才刚刚开展，环境影响仅限于笼统的描述，对水资源利用和调配过程中出现的各种生态、环境问题的研究还比较薄弱，缺乏对区域、流域生态保护和环境管理的分析和评价。隐含的科学问题是：水利规划环境影响评价是一项复杂而且要求创新的研究工作，研究应该向着定量化的具体指标进行，包括关键指标确定、评价方法以及指标体系等内容。本文在此背景下开展了水利规划环境影响评价有关指标及评价的研究工作。针对水利规划项目多、开发周期长的特点，论文选取水利规划中比较典型的规划---大型调水工程规划，着重开展调水工程的规划环境影响评价关键指标的研究：其一是生态环境关键指标，以往的评价只单纯考虑水利工程建设后对区域生态环境的影响，针对影响提出各种减缓措施，未能考虑规划建设布局与区域环境之间的协调问题，论文通过对区域进行生态适宜分区，分析、判断规划建设与区域生态环境的协调性，对规划设立反馈机制，达到调整和完善规划的目的；鉴于区域生态环境的质量与实际用水量关系较大，论文研究了基于区域水分适宜情况下的水资源配置，根据区域水量平衡、水热平衡关系确定包括区域水分适宜下的调水规模、区域水量阈值及环境用水量等指标。研究认为，生态分区指标和水资源配置指标是水利规划环境影响评价的关键指标，对这些指标分析计算的过程同时也是对规划环境影响的评价过程，论文还将文中提出的两类关键指标与毗河调水工程相结合，开展了案例研究。毗河调水工程是都江堰灌区续建的配套项目，其建设可充分发挥都江堰灌区水资源的综合利用和节水改造效益，不仅能解决毗河灌区内农村人畜饮水困难，保障农业可持续发展，还为灌区内生态环境建设提供水资源保障。毗河调水工程规划建设水库8座，总库容7.05 亿m3，其中大型水库2 座，支渠以上渠道共114 条，总长1681.75 km，其中明渠长1540.34 km，渡槽223 座，总长56.02 km，隧洞309 座，总长85.39 km。该区域自然地理、社会经济、水资源条件差异很大、情况复杂，具有很强的研究价值。案例研究结果分析如下：（1）生态关键指标研究毗河调水工程案例研究中选择生物丰度指数、植被覆盖指数、水资源指数、土地退化指数、污染负荷指数5类基本因子，组成调水区生态适宜性评价指标，得出毗河调水区的生态适宜性综合评价B值，在0.067~1.500之间变化；对结果进行再处理、聚类，得出毗河灌区的生态适宜分区。根据区域生态特征和环境要求，对毗河调水工程做出相应的调整。毗河调水工程整体布局较合理，大型建设项目未处于生态特别保护的区域；各水库满足农业灌溉的同时，也能为周围环境提供用水，发挥生态功能，对区域生态与环境有促进作用。（2）水资源配置关键指标研究论文沿用生态环境质量与用水量之间的关系，用区域水量平衡和水热平衡的方法确定生态适宜条件下各水资源参数以及土壤水分通量、水分适宜度等评价指标。研究估算了基于生态与环境质量的毗河调水工程调入区的调水规模，调水总量为33亿m3/a，调水总量大于目前设计的规划调水量，说明调水工程对区域环境还处于补水阶段，对区域生态状况有促进改善作用。论文认为在区域水资源配置中，应优先保证调出区下游河道环境需水量。在考虑区域工农业用水及环境用水情况下，区域可利用水资源量存在阈值。计算了毗河调水区可利用水资源量阈值区间，为9.56-39.8 亿m3/a，低于该水资源量阈值区域生态、环境将遭受严重恶化，生态系统不能维持正常功能，农业生产也将受到限制；高于该值，区域环境湿涝，需要排水。（3）指标体系及规划环境影响评价采用频率统计法、理论分析法和专家咨询法筛选指标，建立水利规划环境影响评价指标体系，结合案例选择指标组成毗河调水工程环境影响评价指标体系，其中水资源指标集8项、水利规划开发指标集14项、生态、环境发展指标集9项、社会经济发展指标集12项。通过层次分析法计算了指标的权重，不同权重值代表不同准则层、指标层的重要程度；将评价指标进行了标准值的转换，与权重结合得出综合评价指数。总体来看，毗河调水工程远期环境影响要小于近期影响，远期影响集中在毗河调水工程对环境用水量的预留不足，应对规划进行相应的调整；2020年与2003年相比，各项指标评分值提高的有32项、基本持平的有7项、减小的有4项，仅小部分持平或降低。毗河调水工程总体环境影响呈现减缓趋势。

Environmental impact assessment is the precondition of water resources planning, developing and utilization. With the increase of human activities and the demand of water resource, regional and ecological conditions of water resources in China have been changed greatly. Environmental impact assessment in planning is the application of environmental impact assessment on strategic planning level, which coordinates the relation between environmental impact and development. The environment impact assessment in planning is still in its early stage in China. The analysis and assessment of environmental impact were not mature and lack of techniques in ecological protection and environmental management. These mean that innovation is required for water resources assessment. To expand the knowledge of the environmental impact assessment in planning, quantitative studies are needed, which includes the determination of key index, evaluation methods and index system formation.Water conservancy planning is a social-economy-ecology system, which includes many environment impact factors. Considering the limits of ability and time, the paper emphasizes on the key index of water conservancy planning.First, the regional ecology and environment impact caused by built of water conservancy are not treated in a way that emphasis the issue of the harmony between its layout and regional environment. In the thesis the harmony between water conservancy plan and regional ecology and environment is analyzed and estimated by ecological suitability regionalization. The feedback mechanism is set up for regions that are not suitable for water conservancy, so that the water conservancy plan could be adjusted. The key indexes of water resources allocation based on regional water suitability are studied based on regional ecology and environment. Considering water resource balance and water heat balance, the indexes includes water transportation scale, regional water quantity threshold and environmental water demand. The study revealed that ecological regionalization and water resources allocation are key indexes of environmental impact assessment of water conservancy. The Pihe river water supply plan was studied by combining of the two key indexes.Pihe river water supply plan is associated with the extended project of Dujiangyan irrigation area. It can not only solve the lack of drinking water for human and livestock, but also guarantee water supply for agriculture sustainable development and eco-environment construction in irrigation area. There is great variability in geography, social economy and water condition in this area. Pihe river water supply project plans to built 8 reservoirs with 70.5 billion m3 capacity, there are 2 large scale reservoirs, 114 canals which sum to 1681.75 km long, in which 1540.34 km are open channels, and 223 aqueducts with length of 56.02 km and 309 tunnels with length of 85.39 km.In the Schemes of Water Supply Works in the Pi River Basin, five indexes are used. The result of ecological applicability evaluation is denoted by B values, which varies from 0.067 to 1.500. Then the Pi River Basin is divided to several regions by ecological applicability evaluation. According to the demand of environmental protect, water resources planning is adjusted .In general, the layout in the Schemes of Water Supply Works in the Pi River Basin is reasonable. Based on the relationship between eco-environmental quality and water consumption, this paper determined appropriated parameters of water resources, soil water flux and water amenity degree for ecological amenity based on regional water equilibrium and water-heat equilibrium, In this research, the scale of water transfer is estimated as 3,300,000,000 m3/a, which is more than the planned water transfer quantity. It indicates that the project of water transfer will help water replenishment in the area and will promote the regional ecological condition.Based on frequency statistic method, theoretic analysis method and expert consultation method, indexes are compared and four ideal index collections. In the case study, some indexes in the general index system are used in comprehensive environmental impact assessment of water resource planning for the Pi River, which includes eight indexes for water resources, fourteen indexes for hydraulic resource development, nine indexes for ideal eco-environmental development, and twelve indexes for social economic development. Analytical hierarchy process was adopted to calculate the weight of index, and different weights represent different rule hierarchy and important degree of index hierarchy. The practice assessment indexes switched to standard values, combining with the comprehensive assessment indexes derived from weight, were used to analysis and evaluate the environmental impact degree of the plan.From the point of comprehensive assessment result of water supply works in the Pi River is concerned, the environmental impact in the long term is less than that in the short term. The former focus on the pre-assigning water quantity for environmental use is insufficient; therefore it is necessary to regulate the plan. There are higher scores in thirty-two items, less variable scores in seven items and little smaller scores in four items in all the indexes when comparing the scores in 2020 to those in 2003. The total environmental impact embodies a slow trend, which shows that the impact is acceptable and the plans of water supply works in the Pi rive are practicable.