Adding sand to an old property

[Sidewinder]

Hi all,

I bought a 1960's lake front home last Summer and have been renovating the house up until now. The lake front side of the property is about 116' long and has rocks up the shore line until right in front of the house where the grass slopes into the water.

I bought the home from a 83 year old women she has not used the house in the past 15+ years and the grass has taken over where she called her beautiful beach I felt bad for the lady I think she thought the property was the way she left it a long time ago.

Now the house is almost renovated and I have 15+ years of yard work to do what do I have to do about adding sand to the beach? I have done everything by the book Including applying for a dock even though there is the dilapidated dock in the water on my property, got elect, plumb and building permits.

Can I just add sand? If not has anyone been in this situation? Who do I call.... DES?