; (C) supports, revitalizes, and encourages the growth of existing communities and maximizes the cost-effectiveness of existing infrastructure; (D) promotes economic development and economic competitiveness; (E) preserves the environment and natural resources and increases community resilience to natural or anthropogenic environmental disasters; (F) protects agricultural land, rural land, and green spaces; and (G) supports public health and improves the quality of life for residents of, and workers in, the community. (11) Location-efficient The term location-efficient characterizes mixed-use development or neighborhoods that integrate housing, transportation choices, commercial development, and facilities and amenities— (A) to lower living expenses for working families; (B) to enhance economic and physical mobility; (C) to encourage private investment in transit-oriented development; and (D) to encourage private sector infill development and maximize the use of existing infrastructure. (12) Long-term affordable housing The term long-term affordable housing means housing that is affordable housing for a period of not less than 30 years. (13) Low-income family The term low-income family has the meaning given the term in section 3(b) of the United States Housing Act of 1937 ( 42 U.S.C. 1437a(b) ). (14) Metropolitan planning organization The term metropolitan planning organization means a metropolitan planning organization described in section 134(b) of title 23, United States Code, or section 5303(b) of title 49, United States Code. (15) Office The term Office means the Office of Sustainable Housing and Communities established under section 5. (16) Regional council The term regional council means a multiservice regional organization with State and locally defined boundaries that is— (A) accountable to units of general local government; (B) delivers a variety of Federal, State, and local programs