(1) In order to better understand current water use and instream flows in the Columbia river mainstem, the department of ecology shall establish and maintain a Columbia river mainstem water resources information system that provides the information necessary for effective mainstem water resource planning and management.

(2) To accomplish the objective in subsection (1) of this section, the department of ecology shall use information compiled by existing local watershed planning groups, federal agencies, the Bonneville power administration, irrigation districts, conservation districts in the basin, and other available sources. The information shall include:

(a) The total aggregate quantity of water rights issued under state permits and certificates and filed under state claims on the Columbia river mainstem and for groundwater within one mile of the mainstem; and

(b) The total aggregate volume of current water use under these rights as metered and reported by water users under current law.

(3) The department of ecology shall publish the aggregate data on the department's website no later than June 30, 2009, and shall periodically update the data.

(4) For purposes of this section, the definition of Columbia river mainstem in RCW 90.90.030(11) shall apply and the use of the definition is solely limited to the purpose of collecting data to meet the information requirements of this section.