A restricted zone around a surface water intake of ____________ feet radius shall be established and all recreational activities prohibited.

The establishment of a restricted zone around a surface water intake is crucial for protecting water quality and ensuring safe drinking water. A restricted zone of 200 feet radius serves to minimize the potential for contamination from recreational activities that may occur in the surface water. By prohibiting these activities within this designated area, the risk of pollutants entering the water source is significantly reduced, thus safeguarding public health and maintaining the integrity of the water supply.

The choice of 200 feet is aligned with regulatory standards that aim to create a balance between water protection and permissible activities around it. This specified distance is seen as effective for managing potential sources of pollution while still allowing some recreational access to areas beyond the intake.

The other distances specified in the options, such as 500 feet, 800 feet, or 1000 feet, may be too restrictive or impractical in many contexts, potentially limiting beneficial uses of the water body without a proportionate increase in protection. Therefore, the 200-foot radius is a well-considered and established standard in managing surface water intake areas effectively.