These are the origins of the files in this gist, and some more useful bits of information. Full isclosure, I am very involved in both of these projects:
The flowlines are from the National Hydrographic Dataset, medium resolution. You can read more about the nhd here Unfortunately, your little creek is too little to be included, but in a few years, it will be there as high-resolution hydrography (NHD-Highres) spreads across the country.
The data is actually served by the Network Linked Data Index, which is a just-launched tool for linking data and sites upstream and downstream of each other. You can learn more about it here: http://cida.usgs.gov/nldi/about or at the github repo for the project
The nhd_streamlines comes from this service call:
The rest of the data comes from the Water Quality Portal, a cooperatively supported tool by the EPA and USGS that serves as a single point of access for accessing water quality data collected by the USGS, EPA and 450 other partner agencies.
The portal has a page for each site, with metadata bout the site. A useful site to explore the area you are interested in is here, which is in a site on the golf course to the west of Barbee Chapel Road:
http://www.waterqualitydata.us/provider/STORET/21NC03WQ/21NC03WQ-BB96/
It shows the sites and flow lines 10 miles up and downstream from the site, as well as metadata about that site. You can also use the map to "walk" up and down the stream network by choosing other sites of interest. The Waterqulaity Portal is indexed in the Network Linked Data Index.
WQP Sites along the flowlines can be collected with this service call (the WQP_stations.json):
- CSV: http://www.waterqualitydata.us/Station/search?nldiurl=http%3A%2F%2Fcida.usgs.gov%2Fnldi%2Fhuc12pp%2F030300020607%2Fnavigate%2FUT%2Fwqp%3Fdistance%3D&mimeType=csv&zip=yes&sorted=no
- geosjon: http://www.waterqualitydata.us/Station/search?nldiurl=http%3A%2F%2Fcida.usgs.gov%2Fnldi%2Fhuc12pp%2F030300020607%2Fnavigate%2FUT%2Fwqp%3Fdistance%3D&mimeType=geojson&zip=no&sorted=no
Sites with Nutrients in the area (the WQP_stations_nutrients.json):
- CSV: http://www.waterqualitydata.us/Station/search?nldiurl=http%3A%2F%2Fcida.usgs.gov%2Fnldi%2Fhuc12pp%2F030300020607%2Fnavigate%2FUT%2Fwqp%3Fdistance%3D&characteristicType=Nutrient&mimeType=csv&zip=yes&sorted=no
- geoJSON: http://www.waterqualitydata.us/Station/search?nldiurl=http%3A%2F%2Fcida.usgs.gov%2Fnldi%2Fhuc12pp%2F030300020607%2Fnavigate%2FUT%2Fwqp%3Fdistance%3D&characteristicType=Nutrient&mimeType=geojson&zip=no&sorted=no
You can also download the Nutrient Results from the sites above as a CSV: http://www.waterqualitydata.us/Result/search?nldiurl=http%3A%2F%2Fcida.usgs.gov%2Fnldi%2Fhuc12pp%2F030300020607%2Fnavigate%2FUT%2Fwqp%3Fdistance%3D&characteristicType=Nutrient&mimeType=csv&zip=yes&sorted=no
From there, you are mostly on your own for the data analysis. If you are an R person, you can use the dataRetrieval R package to do a lot of this work, and then do a lot more fancy analysis.