; (iii) address the most urgent public health and environmental needs, as determined by the heads of the Regional offices for Regions 6 and 9 of the Environmental Protection Agency; and (iv) maximize sustainable practices, such as water reuse and water recycling, natural and green infrastructure, water efficiency, and conservation. (f) Terms and conditions The Administrator may establish such terms and conditions on assistance provided under the program as the Administrator determines appropriate. (g) Cost share The Administrator may establish a Federal share requirement for any project carried out using any assistance proved under this section on an individual project basis. (h) Regional allocations The amounts made available to carry out this section shall be made available in equal amounts for use by the Regional offices for Regions 6 and 9 of the Environmental Protection Agency. IV Miscellaneous 401. Role of the Commissioner and international agreements (a) Wastewater and stormwater authority The Commissioner may study, design, construct, operate, and maintain projects to manage, improve, and protect the quality of wastewater, stormwater runoff, and other untreated flows in the Tijuana River watershed and the New River watershed. (b) Tijuana and New River projects within the United States The Secretary, acting through the Commissioner, shall— (1) construct, operate, and maintain projects that— (A) are on a priority list developed under section 104(c) or 204(c); (B) are within the United States; and (C) improve the water quality of the Tijuana River watershed or the New River watershed, as applicable; and (2) use available funds, including funds received under this Act, to construct, operate, and maintain the projects described in paragraph (1). (c) Agreements with Mexico The Secretary, acting through the Commissioner, may execute an agreement with the appropriate official or officials of the Government of Mexico for— (1) the joint study and design of stormwater control and water quality projects