The Bonnet Carre Spillway is about ten miles west of New Orleans International Airport. This is a floodway which is occasionally used to relieve high water on the Mississippi River by diverting some of it to Lake Pontchartrain, and is the heart of the Reserve-Bonnet Carre Spillway Christmas Bird Count circle. The undeveloped land of the spillway is over ten square miles of fields, marsh, and weedy waste areas, with some woodlands. The area can be interesting at any time, and is especially so in winter.