Kayak storage?

[redknot.livejournal.com]

I live in Davis Square, and I have a kayak that I want to store somewhere not too far away (or somewhere T accessible) so I can use it maybe once a week. I don't mind paying for storage, so long as my kayak is adjacent to some water. I looked into the wonderful Charles River Kayak, and their T-accessible storage is expensive. Can anyone recommend a good spot / body of water to keep my kayak?