i had a similar problem. my 3 acres is the only real water that drains into the pond. its aboout 8/10 of an acre 660 feet around. i did a few things.
trenched the down spouts, driveway drain, and sump pump to the pond. doesnt add a lot of water, but basement is dry .
i added and elbow to the overflow pipe, with a small extension.
the guy who dug my pond was nice enough to come back with his laser and shoot the sides to tell me where the water level will be when it fills up. then i put a 6 inch or so layer of pea gravel on the safety ledge all the way around. does 3 things. 1 helps with erosion. 2 filters the run off, pond stays clearer and 3 when the fish make a bed to spawn, they stay intact, used year after year, and when the fan them out, it doesnt stir up the mud. then on the sides of the pond from the pea gravel to the water line i had rip rap delivered. the pond looks nice when the water is low, and when its up it created shelter for minnows and fry, and slightly deterred the great blue herrons. did not get rid of em but they dont use my pond for a buffet as much. i need to add more rip rap here and there 90 % of it is done. i went light in the areas i dont see from the house . i can post pics if youd like. good luck
