(1) Ecology finds there to be certain locations where water is potentially available on a year-round basis for future groundwater withdrawals. Ecology further finds that withdrawals in these areas are unlikely to affect surface waters closed in WAC 173-527-070, Table III or instream flow values protected under RCW 90.54.020(3). Such regional supply areas are recognized in the watershed plan and supported by the public interest as preferred locations for developing future water supply. Groundwater withdrawals (including permit-exempt withdrawals) may be commenced in the designated regional supply areas to the extent such withdrawals are consistent with chapters 90.03 and 90.44 RCW, and any other applicable requirements of law.

(2) Based on local hydrology, ecology finds that groundwater withdrawals made in areas designated below meet the conditions for regional supply areas in subsection (1) of this section and are so designated:

(a) All lands west of Interstate Highway 5, north of the East Fork Lewis River, and east of the Lewis River mainstem;

(b) All lands west of Interstate Highway 5, north of Lewis River mainstem, and within the Lower Lewis subbasin.

(3) Ecology, in consultation with the department of fish and wildlife, may by order designate other regional supply areas that meet the criteria in subsection (1) of this section.

(4) In order to protect instream values of surface waters in regional supply areas, ecology reserves the right to deny any withdrawals whereby drawdown effects from pumping would create a significant impact to local surface waters. For the purposes of this section, significant impact includes but is not limited to a noticeable reduction in lake level or flow in local streams.