Complex sentence: Some of this water comes from the Schoharie Reservoir via the 16-mile (25.6 kilometre) Shandaken Tunnel, which empties into the Esopus Creek.
Split into simpler sentences: Some of this water comes from the Schoharie Reservoir. It flows through the 16-mile (25.6 kilometre) Shandaken Tunnel, and empties into the Esopus Creek.