Vernal pool construction?

[otofrog]

Hello everybody. There's a large puddle on the edge of my property that is about an inch deep. The only thing that lives in there are pond snails. Whenever it rains, it fills up for around 3 or 4 weeks because of the clay in the soil here, so it would be filled up for a while with all the rain we get here in NJ during the spring and summer. How would I go about digging it a foot or two deeper so more water builds up and all the frogs and salamanders here could lay their eggs? Would it be a good idea to cut some trees down around it so more sunlight comes down and i can plant some bog plants around? Thanks