The board of commissioners of any district created under this chapter shall have the authority to enter into cooperative agreements with the state or federal government, or both, to obtain financial assistance in the form of loans or grants as may be available from the state or federal government, or both. The board of commissioners may execute and deliver at private sale notes or bonds as evidence of the indebtedness in the form and subject to the terms and conditions as may be imposed by the state or federal government, or both. The board of commissioners may pledge the income and revenues of the district, or the income and revenues from any part of the area embraced in the district, in payment thereof. The district may do all things necessary to secure the financial aid or cooperation of the state or federal government, or both, in the planning, design, construction, operation, maintenance or improvement of projects of the district.