UNSPSC 47101538: Sludge or sewage digesters

UNSPSC 47101538 Sludge or sewage digesters (Commodity) covers engineering design, upgrade construction services, and liquid-sludge hauling across municipal wastewater treatment plants. Recent solicitations show state and local bodies procuring detailed design and permitting for sludge-storage tank upgrades meeting capacity standards, full construction-phase engineering oversight, and multi-site recurring sludge-transport services on a per-gallon basis. The Maryland Environmental Service and county boards of commissioners dominate the issuing-body mix, with the Maryland Environmental Service running multiple competitive sealed-bid procurements for hauling services under small-business reserve set-asides and unrestricted competitions. Engineering design work requires multi-disciplined firms with PE-licensed principals and process engineers holding Maryland licensure and ten-plus years of relevant wastewater-plant experience; hauling contracts demand closed tanker trucks with vacuum/pumping systems, five years of documented Maryland liquid-waste experience, and county-issued permits under COMAR 26.04.06 and 40 CFR compliance frameworks.

Maryland dominates recent activity, with the Charles County Board of Commissioners seeking engineering design services for aerated sludge holding tank upgrades at Mattawoman Wastewater Treatment Plant (RFP, due July 30, 2026, estimated $1.5 million total project cost with initial FY 2026-2027 phase at $350,000), and the Maryland Environmental Service issuing back-to-back sealed-bid invitations for liquid-sludge hauling from multiple treatment plants in Washington, Frederick, and Carroll Counties (SBR procurement 1262665 due June 29, 2026 covering four facilities with approximately 586,000 annual gallons; IFB 1262625 due May 26, 2026 covering six school and residential WWTPs with approximately 309,000 annual gallons). Engineering proposals are scored on project understanding, staff experience, firm track record with similar-capacity projects exceeding $10 million, and price. Hauling awards go to responsive low-bidders; contractors assume regulatory liability, spill cleanup, and vehicle maintenance while the procuring authority covers permit and disposal fees.