Which of the following is considered a prohibited discharge in stormwater management?

The discharge of wastewater from concrete washout is considered a prohibited discharge in stormwater management because it contains high levels of pollutants, including sediments, chemicals, and heavy metals from concrete and other materials. This type of wastewater can disrupt the natural water quality of local water bodies, harm aquatic life, and contribute to water pollution. Proper management and disposal of concrete washout are essential to ensure compliance with environmental regulations and to protect water quality.

In contrast, rainwater runoff, groundwater, and filtered water typically do not contain the harmful pollutants found in concrete washout and may be managed differently under stormwater regulations. Rainwater runoff is a natural occurrence, and groundwater is often considered a vital component of the hydrological cycle. Filtered water, assuming it has been adequately treated, is generally safe for discharge as it meets specific water quality standards.