If it's anything like power plants in the US, then there are restrictions on the allowed deltaT above ambient, and for good reason. For example in California, t

If it's anything like power plants in the US, then there are restrictions on the allowed deltaT above ambient, and for good reason. For example in California, the San Onofre Nuclear plant was found to significantly impact the local fisheries by killing fish larvae and damaging kelp forests, and I believe the deltaT is less than 2 degrees C. (Though I'm not sure if this is at the heat exchanger or at the diffuser head). At Morro Bay (also in California) there is a power plant built long before such restrictions existed and it dumps cooling water straight into the surf zone. Apparently, intertidal species (muscles, snails, etc) can be found there that are typically found much further south. I can personally report that it makes the surfing much more pleasant, but the heated water is generally considered a form of pollution due to the negative impacts on native species.