Outdoor swimming near Warszawa? (Warsaw)

I was wondering if anyone can recommend a lake, river or outdoor aquapark in Warszawa or nearby where i can cool of from this heat we have at the moment?

I hear there are some lakes not far from Warszawa where a lot of people go when its warm weather like now - can anyone tell more about them?

How are the facilities there, are there shops where you can buy drinks and food or will i need to bring on my own?

Thanks in advance!

Maybe this one

wodnypark.com.pl/kontakt,en

They used to have the lido below too - not sure if they have refurbished it since the pics were taken!