There is no lake in Karpacz, but there is the Łomnica Reservoir at the Łomnica dam, and higher in the mountains near the Samotnia shelter, you will find the Small Pond and nearby the Great Pond.
The nearest thermal baths are in Cieplice (Jelenia Góra), but there are many facilities with water parks in Karpacz, such as Hotel Sandra SPA or Hotel Gołębiewski.