Nope, this cache is not hidden in the lake.  You will need to solve the following puzzle to find the cache container.  

From Wikipedia:  "Star Wars Day is an informal commemorative day observed annually on May 4 to celebrate the Star Wars media franchise created by filmmaker George Lucas. Observance of the day spread quickly through media and grassroots celebrations since the franchise began in 1977.  The date originated from the pun "May the Fourth be with you", a variant of the Star Wars catchphrase "May the Force be with you". Even though the holiday was not created or declared by Lucasfilm, many Star Wars fans have chosen to celebrate the holiday. It has since been embraced by Lucasfilm and the Walt Disney Company as an annual celebration of Star Wars."

You will find the cache at: 

North 43 AB.CDE  West 89 FG.HIJ

A=

B=

C=

D=

E=

F=

G=

H=

I=

J=

Check the sum.  A+B+C+D+E=24, F+G+H+I+J=21