Based on NHDPlus layer (`flow_lines`) that includes the hydro sequence of the next downstream segment, this function systematically moves downstream, identifying the next downstream hydro sequence, until it reaches a pre-determined hydro sequence number, at which point it stops.
findDwnstrmHydroseg(hydro_id, flow_lines, hydro_pause_ids)a character or numeric input containing the starting hydro sequence
An `sf` object containing the flowlines (output of `queryFlowlines()`). Must have a column name called Hydroseq with unique identifiers, and a column name called DnHydroseq containing the hydro sequence of the next downstream segment
a vector of hydro sequences containing possible end points
character of the nearest downstream HY segment to starting segment that falls within a list of possible stopping segments.