调节库容 meaning in English

balancing storage
pondage
regulator storage

But for the reservoir water - supply system , the reservoir whose oam cost is low and flow into the reservoir is more may be selected to be taken advantage of the storage capacity of this kind of increase to regulate some water yield more and in order to substituting the water supply of the other water supply projects whose oam cost is comparatively higher , so that to achieve the goal of the oam saved , that is to say , that can utilize this regulation capacity increased of the reservoir to optimize operation between the raw water systems so that to save the oam of the system . namely , it can obtain a certain economic benefits to utilize this kind of difference between water supply ability and reality water - using levels existing for a long time
从长春市供水系统长期规划和目前供水现状研究得出，在目前和今后的长时期内长春市供水系统的供水能力总是大于实际用水水平。这种长期存在的差别对松花江供水只意味着减少抽水量。但对水库工程供水系统则可挑选运行费用低的、入库水量较多的某个水库，利用这种增加的调节库容多调节出一些水量，以替代运行费用较高的供水工程的供水。