An archaeological watching brief was undertaken by Colchester Archaeological Trust in June/July 2011 during the replacement of a stretch of water-main on land to the south of Town Wall House, 4 Balkerne Hill, Colchester. <1> This work followed on from an attempt to repair the water-main in August 2010, which was also monitored by CAT (CAT Report 571).<2> Four monitoring visits were made during the excavation of the 22m-long trench. The southern end of the trench was excavated through tarmac, hoggin and dark greyish-brown sandy silt to a depth of 0.65m below modern ground-level. The sandy silt contained modern brick and tarmac fragments and continued below the base of the trench. The trench was increased in depth to approximately 1m below modern ground-level where it crossed the pavement, access road to the car-park and the car-park itself. Layers associated with the modern hardstanding directly overlay natural orange sand at a depth of 0.7m below modern ground-level. The trench was cut through modern hardstanding and underlying natural sand or the backfill from other modern service-trenches. It was evident that the present ground surface is below the level of the base of the town wall foundation, indicating that the area has been heavily reduced in level at some time. No significant archaeological remains were observed and no archaeological finds were recovered.