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+Depression-Filling
+==================
+
+Depressions, otherwise known as pits, are areas of a landscape wherein flow
+ultimately terminates without reaching an ocean or the edge of a digital
+elevation model.
+
+Depressions, Pits, and Sinks
+----------------------------
+
+Depressions have been called by a variety of names. To clarify this mess,
+Lindsay (2016) provides a typology which is followed here:
+
+.. image:: imgs/Lindsay2016_depression_typology.png
+
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+Flow Accumulation
+=================
+
+TODO
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