In-water Concrete Use
Where possible, poured concrete should be excluded from contact with surface or groundwater during initial curing, ideally for a period of 30 days after it is poured. During that time, runoff from the concrete will not be allowed to enter the surface or groundwater. If this is not feasible due to expected flows and site conditions, commercial sealants that are appropriate for use near water may be applied to the poured concrete surface to prevent exposure of uncured concrete to streamflow and subsequent risk to water quality and aquatic life before the sealant comes into contact with flowing water. If sealant is used, water will be excluded from the site until the sealant is dry and fully cured according to the manufacturer’s specifications. Concrete is considered to be cured when water poured over the surface of concrete consistently has a pH of less than 8.5.