Layer Estimates:

Layer: Existing_Dams (ID:1)
Count: 108
Extent:

XMin: -7963263.33539237
YMin: 5167257.80160683
XMax: -7910399.51863312
YMax: 5225602.78609143
Spatial Reference: 102100 (3857)

Layer: Charles_River (ID:2)
Count: 63
Extent:

XMin: -7963264.20869897
YMin: 5165756.66266321
XMax: -7909476.28733439
YMax: 5227462.51938169
Spatial Reference: 102100 (3857)

Layer: CRW_Boundary (ID:3)
Count: 1
Extent:

XMin: -7964871.89590037
YMin: 5164704.42349515
XMax: -7909416.02963573
YMax: 5229252.31378051
Spatial Reference: 102100 (3857)