(a) Authorization of appropriations There is authorized to be appropriated $1,500,000,000 to the Secretary to carry out this section. Such sums shall remain available until expended. (b) Low-Income household drinking water and wastewater assistance The Secretary shall make grants to States and Indian Tribes to assist low-income households, particularly those with the lowest incomes, that pay a high proportion of household income for drinking water and wastewater services. (c) Use of LIHEAP resources In carrying out this section, the Secretary, States, and Indian Tribes, as applicable, shall use the existing processes, procedures, policies, and systems in place to carry out the Low-Income Home Energy Assistance Act of 1981, as the Secretary determines appropriate, including by using the application and approval process under such Act to the maximum extent practicable. (d) Allotment (1) Factors The Secretary shall allot amounts appropriated pursuant to this section to a State or Indian Tribe taking into account— (A) the percentage of households in the State, or under the jurisdiction of the Indian Tribe, that are low-income, as determined by the Secretary