COSTA MESA

Mesa Consolidated Water District will spend $20,000 to increase the height of a wall between Westminster Avenue and an 18-million-gallon reservoir at the Lindbergh School site to meet terms of a settlement with residents.

A 6-foot-high sound wall was installed as part of an agreement reached in 1992 between 30 residents and the water district, officials said. The height discrepancy was discovered by a resident who was installing fencing. Although the wall is 6 feet tall on her side of the fence, it is only 4 feet, 9 inches on the other side, where the ground is higher.

Mesa already has paid about $594,000 for mitigation measures, including wind-monitoring devices and mufflers. The district also paid about $260,000 for house cleaning, air conditioning, insulation and double-paned windows.