NAD83(2011) Illinois State Plane East zone US survey feet NAVD88 MSL Geoid 12a US survey feet id, east, north , height f1,771370.107,521480.309,439.970 f2,816043.674,515594.576,453.090 f3,845387.478,526564.053,552.709 f4,873275.350,515779.159,451.423 f5,759381.492,495052.433,423.785 f6,796537.111,494671.154,391.302 f7,833752.474,493879.634,428.746 f8,870234.506,484039.200,470.826 f9,759085.450,468224.009,421.708 f10,809929.624,467955.651,423.296 f11,838143.653,470872.228,462.985 f12,871196.621,466604.447,509.435 f12b,871196.615,466604.410,509.330 f13,752315.551,441475.595,397.499 f13b,752315.565,441475.579,397.457 f14,789743.441,441348.118,427.801 f15,833958.012,438689.717,420.790 f16,868164.148,438383.097,425.232 f17,852836.049,481279.949,461.958 f18,833413.083,516866.034,483.221 f19,775055.106,463025.616,425.997 f20,780811.061,509285.102,479.996