AbstractWash water, municipal solid waste incineration (MSWI) fly ash, and propylene (PP) fibers were employed simultaneously to produce self-compacting repair mortar (SCRM). Different SCRM mixtures were utilized, incorporating 35, 70, and 140 kg/m3 of MSWI fly ash, along with 0.1% of PP fibers. The research focused on investigating the workability, mechanical properties, and global warming potential (GWP) of SCRM. The incorporation of MSWI fly ash and wash water in SCRM resulted in reduced workability, necessitating an increase in the use of superplasticizer. Adding MSWI fly ash decreases compressive strength. The minimum compressive strength was observed when employing 140 kg/m3 of MSWI fly ash and wash water instead of tap water simultaneously. By increasing the proportion of MSWI fly ash content and correspondingly reducing the cement content in SCRM samples, there was a decrease in flexural strength. The ultrasonic pulse velocity (UPV) of all SCRM samples falls within acceptable range. Adding MSWI fly ash to SCRM reduces fracture toughness, and the concurrent use of wash water and MSWI fly ash significantly decreases fracture toughness. Incorporating PP fibers into SCRM resulted in increased compressive strength. Utilizing wash water and MSWI fly ash in SCRM significantly reduces GWP. The avoidance of wash water consumption mitigates the environmental impact of SCRM.