Cecil is not alone on his drain posture. There are a number of Pondmeisters that see drains as nothing more than a potential for failure. This is a respectable attitude. OTOH, tho, there are many that were installed with the best practices and they function fine. Also, I remember a conversation I had with Mike Otto when I was preparing to construct the drain and dam for out project. Amongst the numerous words of wisdom he imparted, he did state that "all drains leak". It came with all the dotted "I's" and crossed "T's" for proper drain installation. I take this to mean the obvious "do it correctly and it will be fine".