The original storage capacity of the Xiaolangdi reservoir was artificially calculated with a planometer as per the topographic map (Scale 1:10000) aerial surveyed more than 30 years ago in 1966.

• 黄河小浪底水库设计阶段使用的原始库容是依据1966年航测的1:1万地形图,利用求积仪人工量算的,距今已30余年。