Accounts Payable Supervisor

Summary

Wastewater Treatment Division's Finance section is hiring for an Accounts Payable Supervisor. Join one of the nation’s largest wastewater treatment agencies and lead the creation of a centralized accounts payable function in the Wastewater Treatment Division. This is a unique opportunity to shape a new team, establish efficient workflows, and ensure compliance while safeguarding ratepayer funds. You’ll work closely with WTD procurement staff and King County’s central procurement and payables teams to ensure accurate, timely payments that comply with our contracts, while safeguarding water quality, the environment, community resources, and supporting our equity and social justice objectives.

This role will lead a new team within the Wastewater Treatment Division (WTD) Finance section. The successful candidate will centralize the accounts payable function in Finance, identify gaps in WTD’s current processes, and implement new strategies to reduce risk and ensure alignment with King County accounts payable and industry standards. They will also provide guidance and support to internal WTD customers on accounts payable needs and work closely with WTD’s procurement staff to ensure contract terms and conditions related to invoicing are followed.

The role will assist in hiring and supervising a new team of accounts payable support staff. This position follows a hybrid work model, blending remote and in-person work.

The Accounting Unit within the Finance section is responsible for accounts receivable, revenue recognition, and associated audits; accounts payable; accounting for debt, capital assets, and capitalization policies; and the preparation of stand‑alone financial statements in accordance with applicable accounting standards. The unit also manages and coordinates the annual external audit, ensuring timely, accurate, and transparent financial reporting and compliance with regulatory requirements.

You will help lead a Finance & Administration section that provides services including budget development & oversight, capital finance, procurement & contracts administration, technology services, central service administration (i.e., Division Fleet management), accounting, audit & compliance, rates & financial planning, payroll, and billing & accounts receivable.

King County is a diverse and vibrant community that represents cultures from around the world. Our True North is to create a welcoming community where everyone can thrive. We prioritize equity, racial and social justice, making it a foundational and daily expectation for all employees. In this role, you will actively apply these principles in all aspects of your work.

• Supervise and lead the Accounts Payable (AP) team, including hiring, training, work assignment, performance management, and staff development.
• Oversee all AP operations, including invoice processing, purchase order matching, vendor setup and maintenance, payment approvals, P‑Card administration, and employee reimbursements.
• Ensure accurate, timely, and compliant processing of payments in accordance with policies, regulations, and internal controls.
• Evaluate and improve AP processes through gap analysis; implement enhancements in collaboration with procurement and finance partners.
• Develop and maintain AP policies, procedures, and standard operating practices to strengthen internal controls, mitigate risk, and support audit readiness.
• Coordinate fiscal year‑end close activities, including accruals, reconciliations, and cutoff procedures.
• Support internal and external audits by preparing documentation, responding to inquiries, and implementing corrective actions.
• Serve as the primary AP liaison to internal stakeholders, Central Payables, and vendors; resolve issues and ensure continuity of operations.

• Supervisory & Leadership Experience
  • Experience supporting and guiding a team, including participating in hiring and onboarding, providing coaching and feedback, assisting with performance management, helping with work planning, and fostering staff development and…