I live in Southern California, Rancho Palos Verdes, and was a member for about 3-4 years 5 years ago. Wilderness Unlimited has a couple of waterfowl properties in Imperial County. One just NE of El Centro, and one NW of Calipatria, both have in place dugout blinds. I have hunted both for doves, but not waterfowl. As is the case with all hunting, weather is the determining factor on productivity each year. 
I understand for Northern California they have some very good properties for waterfowl and quail. For Southern California I don't reccomend them. Their information sheets were out of date for a number of the properties we hunted for quail. A tad bit expensive for what we got for S. California, but could be good fo the Sacramento, and San Joaquin  Valleys. Herb 
