This bill amends existing law (RCW 90.48.260). It designates the Department of Ecology as the state water pollution control agency for purposes of the federal Clean Water Act as it existed on February 4, 1987, requires Ecology to exercise responsibility for the national estuary program jointly with the Puget Sound partnership, and authorizes Ecology to establish and administer a comprehensive state point source/pollution discharge elimination permit program as the sole agency issuing permits required by the national system in Washington, subject to RCW 90.48.262(2). The bill explicitly lists permit program elements Ecology may include (effluent limits, water quality standards, pretreatment, inspections, enforcement including penalties and criminal sanctions, public process, coordination with federal agencies, and user charges) and authorizes Ecology to run financing, construction assistance, planning, area-wide waste treatment management, and basin planning programs. It also assigns the governor responsibility for actions required of the governor under the federal Clean Water Act. The bill allows Ecology to delegate its authority under the chapter, including NPDES authority and duties regarding animal feeding operations (AFOs) and concentrated animal feeding operations (CAFOs), to the Department of Agriculture by memorandum of understanding, but until any such delegation receives federal approval the Department of Agriculture must reach agreement with Ecology before adopting or issuing AFO/CAFO rules, permits, programs, and directives and must ensure compliance with all federal and state water pollution control laws. By statutory requirement, Ecology must offer a watershed-based water quality trading program to any NPDES general permittee that discharges to a waterbody with a temperature total maximum daily load (TMDL) and is not in compliance with its permit; the program may be community-based or market-based and must, whenever feasible, offer incentives for improvements in the built environment or actions addressing urban heat island effects on waters of the state. The text includes specific timing provisions requiring reissuance and updates of NPDES municipal stormwater general permits first issued January 17, 2007 for western and eastern Washington with listed reissue dates, terms, and effective dates, and provides minimum delay dates for certain new permit provisions related to low-impact development, inspections, and smaller project controls. The bill references other RCW sections (90.48.262(2), 90.71.210, and RCW 36.70A.130(4) as it existed on July 10, 2012) whose contents are not included here, and some listed dates are historical relative to the bill header; it is unclear from the extracted text whether additional sections of the bill exist or how those cross-references and historical dates affect implementation.

If enacted, the bill makes the Department of Ecology the central authority for Clean Water Act permitting and programs in Washington, giving Ecology clear authority to run the state point-source permit program, enforce violations, collect user charges, and administer grants or loans for pollution control. Ecology can delegate animal feeding operation (AFO/CAFO) permitting to the Department of Agriculture only by memorandum of understanding and with federal approval; until that federal approval exists, Agriculture must agree with Ecology before issuing any AFO/CAFO water-quality rules or permits. NPDES general permit holders who are not meeting permit limits because of a temperature TMDL must be offered a watershed-based trading option that can include incentives for projects that reduce urban heat island impacts. The groups most affected are the Department of Ecology (more centralized permitting, enforcement, and program administration), the Department of Agriculture (potentially takes on AFO/CAFO responsibilities but with coordination and federal sign-off), municipal NPDES permittees (who may get alternative compliance pathways through trading and could face updated permit conditions tied to past reissuance schedules), and the Puget Sound Partnership and the governor (formal roles in estuary program and federal obligations). The provision could shift regulatory costs and decision making toward Ecology, offer permittees new compliance options that might lower direct control costs, and create uncertainty about AFO/CAFO rulemaking until federal delegation occurs. Key implementation details and why the bill keeps deadlines from 2012–2016 relative to a 2025 bill are not provided in the extracted text and remain unclear.