Rural Water Supply Act of 2005

Rural Water Supply Act of 2005 - Reclamation Rural Water Supply Act of 2005 - Directs the Secretary of the Interior to carry out a rural water supply program in reclamation states to: (1) investigate and identify opportunities to ensure safe and adequate rural water supply projects for domestic, municipal, and industrial use in small communities and rural areas; (2) plan the design and construction, through the conduct of appraisal investigations and feasibility studies, of such projects; and (3) oversee the construction of specified projects recommended in feasibility reports. Requires activities to be carried out in cooperation with a qualifying non-federal project entity.

Directs the Secretary to: (1) develop and publish in the Federal Register criteria for determining the eligibility of a rural community for assistance and for prioritizing requests; and (2) develop a rural water programs assessment.

Sets forth provisions regarding: (1) proposed project appraisal investigations; and (2) recommended project feasibility studies.

Twenty-First Century Water Works Act - Directs the Secretary to develop and publish criteria for determining the eligibility of a rural water supply project for financial assistance. Authorizes the Secretary to make available loan guarantees to lenders for a project meeting the criteria. Authorizes the Secretary and the Secretary of Agriculture to enter into a memorandum of agreement providing for Department of Agriculture financial appraisal functions and loan guarantee administration for activities.