NHD Flowline Upstream Trace

<div>This data represents flowlines in the Roaring Fork watershed to be used in a web map showing connected wetland and deepwater habitat features from the National Wetlands Inventory (NWI) dataset and various hydrographic features from the National Hydrography Dataset (NHD). A connectivity model was used to determine isolation/connectivity using a 0, 5, &amp; 10 meter buffer of features.  The general model process steps include:</div><div><br /></div><div>NWI was used as input data (other data can be added as input e.g. NHD) to determine &quot;seed&quot; jurisdictional waters.  Currently, “seed” jurisdictional waters was defined as all Estuarine, Lacustrine,  Tidal Riverine, Lower Perennial Riverine, and Upper Perennial Riverine NWI features.</div><div>Select all NWI features in the study area that are &quot;potential connectors&quot;.  Currently, “potential connectors” were defined by excluding NWI features that had drier water regimes (temporarily flooded [A], continuously saturated [B], Continuously Saturated [D] and Seasonally Flooded/Saturated [E] and all Palustrine Farmed [Pf] features). </div><div>Select all the &quot;potential connectors&quot; that intersect the &quot;seed&quot; data with the customized buffer distance. </div><div>Continue iterations of step 3 by using the output (“seed” + intersecting “potential connectors”) as the “seed”.   Iterations repeat until the count of selected NWI features does not increase.</div><div>Select all NWI features (including non-connector wetlands) that intersect the final output of step 4.  All selected features are exported as &quot;Connected NWI Features...&quot;.</div><div>Invert the selection and export remaining features as &quot;Isolated NWI Features...&quot;</div>