•_Lay_Schedule_for_72"_.pdf

This is a lay schedule document for a 72-inch water main replacement project managed by the Washington Suburban Sanitary Commission (WSSC) in Maryland. The document pertains to the Large Valve Vault Replacement project located at 1200 W. University Boulevard in Silver Spring, Montgomery County, Maryland, which involves replacement of approximately 87 feet of 30-inch water main, 48 feet of 72-inch water main, and one 30-inch valve and vault. Sealed responses are due by 2:00 p.m. on July 22, 2026 (with subsequent deadline extensions noted for July 29, 2026, and August 19, 2026), to be submitted via WSSC's eProcurement Portal. Construction is anticipated to commence in summer 2025 with completion by fall 2025. The project scope includes replacement of existing prestressed concrete cylinder pipe (PCCP) with Class 54 ductile iron water main (30-inch) and 72-inch steel water main with 7/8-inch wall thickness, both featuring external coating and cathodic protection systems per WSSC standards.

The project carries mandatory compliance with the Maryland Buy American Steel Act, Maryland Little Miller Act requiring 100 percent Performance and Payment bonds, and Maryland prevailing-wage requirements with prescribed wage rates and apprentice payment standards. The contractor must submit payroll records within 14 days of each payroll period to Maryland's Commissioner of Labor and Industry, with $10 per day liquidated damages for late submissions. Five percent retainage will be withheld from all payments, and payment will be made no later than 30 days after receipt of a proper invoice. The cathodic protection system for moderately corrosive soil conditions carries an estimated cost of $42,468.42 and includes PRITEC-coated pipe, insulating joints, five test stations, and multiple zinc anode beds. Additional requirements include tree protection and restoration at a 1:1 diameter breast height ratio (79 inches total), installation of temporary pedestrian trail access to maintain Sligo Creek Trail usage, and full trail restoration upon completion, with water service to affected properties maintained through temporary connections limited to maximum 8-hour shutdowns.