Pros:

Your first.
Nice idea, creative.
Well it's your first and it's a good map.
Detailed.
Bridge.. I like bridges.

Cons:

Too open... Make it more.. I dunno just too open.
Not a good idea for a safehouse to be in a survival map.

Conclusion:

Nice map for a first survival map. I like it, but it's too open and a safehouse in a survival map doesn't make sense.
I like this idea, it's creative. Personally I like bridges to hold off waves of infected. Well I recommend this map. Just make sure your good with the idea of open spaces and stuff.