Tenders Are Invited For Sewerage Work – Pj - Renovation Wwtp Leiden (Dig-18615)

Sewerage Work – Pj - Renovation Wwtp Leiden (Dig-18615). On November 18, 2025, A European Public Tender Was Published Called Adjustment Of Vbt And Renovation Of Gas And Sludge Line Awzi Leiden South West, With Tenderned Reference Tn557420. The Vault Opening Of This Tender Took Place On February 20, 2026. Unfortunately No Registrations Have Been Made. After Evaluating The Tender, It Was Decided To Re-Tender And Change The Assignment Compared To The Previous Tender, See Section 2.5.1 In The Run-Up To This Tender, A Market Consultation Took Place In June 2025. The Market Consultation And The Final Report Can Be Found On Tenderned Under Tenderned Reference Number: 530790. The Current Preliminary Settling Tank (Hereinafter: Vbt) And The Primary Sludge Line At Wwtp Leiden South-West Have A Number Of Issues With Leaching Of The Sludge Bag From The Vbt In Rwa Situations (Rain Return Supply) And Blockages In The Primary Sludge Line. To Address These Issues The Following Work Will Need To Be Carried Out. A Deflection Plate Will Be Installed In The Vbt, Four (4) Additional Sludge Bag Scrapers Will Be Added And Fixed Flushing Points Will Be Installed In The Sludge Bag. In Addition, The Agitator Drive Will Also Be Equipped With A Frequency Converter (Hereinafter: Fo) And The Gear Motor Will Be Replaced So That It Can Run At A Higher Speed. In Addition To These Adjustments, A New Primary Sludge Thickener (Hereinafter Psi) Will Be Realized With A Primary Sludge Pretreatment (Hereinafter Psv). The Following Installations Will Be Installed In The Primary Sludge Pretreatment:  A New Primary Sludge Pumping Station (Hereinafter: Psg), Including The Use Of The Existing Macerators;  A New Thickened Primary Sludge Pumping Station (Hereinafter: Ipg), Including Field Piping To The Sludge Digestion Tank (Hereinafter: Sgt) And The Collection Pit;  Installing A New Strain Press;  Installing A New Sand Trap;  Reuse Of The Existing Sand Washer, Which Must Be Adapted So That It Is Suitable For The New Situation;  A New Ls Room And Installation Of New Switch Cabinets For The New Parts. A New Well Will Also Be Constructed To Drain The Psi. After The New Components Have Been Completed, The Installations In The Existing Primary Sludge Pumping Station Will Have To Be Decommissioned. And The Existing Primary Sludge Pipe In Service Building 2 Must Be Removed, As Well As The Dilapidated (Site) Cables And (Site) Pipes. Due To The Realization Of The New Parts, An Additional Odor Filter Will Have To Be Installed In Addition To The Existing Odor Filter Of The Vbt. For This Purpose, A Released Odor Filter From The Wastewater Treatment Plant Leiden Noord Must Be Reused And The Existing Extraction Fans Of The Vbt Must Be Replaced In Order To Extract The New And Existing Parts.