Let’s get some flow data for the NHDPlus subset included withnhdR package. Our goal is to adjust the color and size of each reach by their average flow.
library(nhdR)library(dplyr)library(ggplot2)library(sf)ggplot()+geom_sf(data = gull$sp$NHDWaterbody)+geom_sf(data = gull$sp$NHDFlowLine)#> old-style crs object detected; please recreate object with a recent sf::st_crs()#> old-style crs object detected; please recreate object with a recent sf::st_crs()#> old-style crs object detected; please recreate object with a recent sf::st_crs()gull_sf<- gull$sp$NHDFlowLineNHDPlus includes two estimates of flow:
eromflow<-nhd_plus_load(4,"EROMExtension","EROM_MA0001")%>%filter(ComID%in% gull$sp$NHDFlowLine$COMID)%>%select(ComID, Q0001F)gull_sf<-left_join(gull_sf, eromflow,by =c("COMID"="ComID"))vogelflow<-nhd_plus_load(4,"VogelExtension","vogelflow")%>%filter(COMID%in% gull$sp$NHDFlowLine$COMID, MAFLOWV!=-9999.00000)gull_sf<-left_join(gull_sf, vogelflow,by ="COMID")gull_sf<- dplyr::filter(gull_sf,!is.na(Q0001F))#> old-style crs object detected; please recreate object with a recent sf::st_crs()gull_sf%>%ggplot()+geom_sf(data = gull$sp$NHDWaterbody)+geom_sf(aes(color = gull_sf$Q0001F),size = gull_sf$Q0001F/20)+labs(color ="EROM Flow (cms)")#> old-style crs object detected; please recreate object with a recent sf::st_crs()#> Warning: Use of `gull_sf$Q0001F` is discouraged.#> ℹ Use `Q0001F` instead.gull_sf<-filter(gull_sf,!is.na(MAFLOWV))gull_sf%>%ggplot()+geom_sf(data = gull$sp$NHDWaterbody)+geom_sf(aes(color = gull_sf$MAFLOWV),size = gull_sf$MAFLOWV/20)+labs(color ="Vogel Flow (cms)")#> old-style crs object detected; please recreate object with a recent sf::st_crs()#> Warning: Use of `gull_sf$MAFLOWV` is discouraged.#> ℹ Use `MAFLOWV` instead.