In the Deep Portion of the Natatio Pool                -      -      - 
(-------------------------------------------------)     W <---(M)---> E
                                                        -      S      -

The pool floor drops into darkness, and you struggle to keep your head
above water.  The clarity of the water has reduced because of the unusual
amount of mud in the water, down below you can make out a malfunctioning
archaic filtering hatch.  The shallow portion of the pool is to your south. 
A man wades through the waters as he bathes himself.