The use of snow-surveys as an aid in flood-control operation of reservoirs

Two types of floods occur on the Sierra tributaries of the San Joaquin River: winter floods from heavy rains, and late spring floods from melting snow. Snow survey data as of April 1 have provided a reasonable accurate forecast of total April through July streamflow. Snow melt floods can be predicted at least a week in advance from snow pack daily temperature data. A hypothetical operation of the proposed Pine Flat Dam is outlined on a policy adopted for the control of rain floods and water conservation aimed to have a full reservoir at the end of the snow runoff period.Tables and graphs illustrate the procedures.Discussions by James E. Jones and H.P. Boardman present agreement in the procedures described and present other factors for consideration for increased accuracy in reservoir operations.