For wastewater with a temperature higher than 40°C, cooling measures should be taken before it is discharged into the urban drainage pipeline. It is generally advisable to install a cooling device, and the main cooling method is secondary evaporation, which involves dissipating heat through the water surface and adding cooling water. It is preferable to use wastewater for cooling purposes. For wastewater with a higher temperature, consideration should be given to recovering and utilizing the heat it contains before applying cooling water to reduce the temperature. When the residual heat in the wastewater cannot be recovered or utilized, secondary evaporation under normal pressure can be carried out first, followed by cooling to reduce the temperature. Cooling ponds are usually located outdoors. If they are installed indoors, the device should be sealed, and manholes and vent pipes leading to the outdoors should be provided.