As a further means of carrying out the policies defined in Sections 12578 to 12582, inclusive, the department shall have the following powers and duties:
(a)
Collect and file data.
(b)
Make necessary studies and surveys.
(c)
Make investigations.
(d)
Prepare plans and estimates of cost and benefits of all proposed water development projects.
(e)
Determine the damage created by flood waters.
(f)
Encourage the creation and development of flood control and water conservation plans and activities of the several counties, cities, state agencies, and public districts.
(g)
Cooperate with the United States or any of its departments or agencies in carrying out measures for control, storage or use of waters on streams, rivers or other waterways, and the watersheds thereof within this State which are authorized and adopted pursuant to an act of Congress of the United States, approved June 22, 1936, entitled “An act authorizing the construction of certain public works on rivers and harbors for flood control, and for other purposes,” together with amendatory or supplemental legislation adopted by Congress.