Amended to use the flood risk data at certain depths as well as the overall risk data. Styling amended to include the Unavailable option.

Author: itsozz

flood_risk/pre-processing.R

@@ -44,22 +44,46 @@ file.remove(shp_files)
 # 5. Change the "File format" drow-down to "GeoJSON"
 # 6. Select the "Download file" button
 # 7. Copy the downloaded file "rofs_4band.json" from your "Downloads" folder to the "flood_risk" folder containing this script
+# 8. Repeat steps 4 - 7 for each of the other flood risk layers based on depths from 0.2m - 1.2m
 
 
-# Load raw flood risk data and tidy up the variables ---------------------------
-trafford_flood_risk <- read_sf("rofrs_4band.json") %>%
+# Function to load raw flood risk data and tidy up the variables ---------------------------
+get_flood_risk <- function(raw_data_filename) {
+    read_sf(raw_data_filename) %>%
     rename(flood_risk = risk_band) %>%
     filter(st_geometry_type(geometry) != "POINT") %>% # Just in case there is any point data, remove it as this will show up as a marker pin on the map which will be confusing. The previous version of this dataset had 6 within Trafford.
     select(object_id = objectid, flood_risk, geometry)
-
-
-# write data  ---------------------------
-file.remove("trafford_flood_risk.geojson") # first remove the previous file
-write_sf(trafford_flood_risk, "trafford_flood_risk.geojson", driver = "GeoJSON")
-
-
-# Clean up the filesystem removing the downloaded flood risk JSON file and the shapefile ZIP ---------------------------
-file.remove(c("rofrs_4band.json", "trafford_and_environs_boundary.zip"))
-
-# reset R's spherical geometry if required ---------------------------
+}
+
+
+# Write data  ---------------------------
+# First remove the previous files
+file.remove(c("trafford_flood_risk.geojson",
+              "trafford_flood_risk_0_2m_depth.geojson",
+              "trafford_flood_risk_0_3m_depth.geojson",
+              "trafford_flood_risk_0_6m_depth.geojson",
+              "trafford_flood_risk_0_9m_depth.geojson",
+              "trafford_flood_risk_1_2m_depth.geojson"))
+
+# Now create the files again based on the new data
+write_sf(get_flood_risk("rofrs_4band.json"), "trafford_flood_risk.geojson", driver = "GeoJSON")
+write_sf(get_flood_risk("rofrs_4band_0_2m_depth.json"), "trafford_flood_risk_0_2m_depth.geojson", driver = "GeoJSON")
+write_sf(get_flood_risk("rofrs_4band_0_3m_depth.json"), "trafford_flood_risk_0_3m_depth.geojson", driver = "GeoJSON")
+write_sf(get_flood_risk("rofrs_4band_0_6m_depth.json"), "trafford_flood_risk_0_6m_depth.geojson", driver = "GeoJSON")
+write_sf(get_flood_risk("rofrs_4band_0_9m_depth.json"), "trafford_flood_risk_0_9m_depth.geojson", driver = "GeoJSON")
+write_sf(get_flood_risk("rofrs_4band_1_2m_depth.json"), "trafford_flood_risk_1_2m_depth.geojson", driver = "GeoJSON")
+
+
+# Clean up the filesystem ---------------------------
+# Removing the downloaded flood risk JSON files and the shapefile ZIP
+file.remove(c("rofrs_4band.json",
+              "rofrs_4band_0_2m_depth.json",
+              "rofrs_4band_0_3m_depth.json",
+              "rofrs_4band_0_6m_depth.json",
+              "rofrs_4band_0_9m_depth.json",
+              "rofrs_4band_1_2m_depth.json",
+              "trafford_and_environs_boundary.zip"))
+
+
+# Reset R's spherical geometry if required ---------------------------
 #sf_use_s2(is_sf_using_s2) # Reset whether sf is using S2 or R2 geometry calculations

flood_risk/styling.R

@@ -1,24 +1,38 @@
 ## Styling flood risk features ##
 
-# load packages ---------------------------
+# Load packages ---------------------------
 library(tidyverse); library(sf)
 
-# read un-styled, cleaned data ---------------------------
-trafford_flood_risk <- read_sf("trafford_flood_risk.geojson")
 
-# apply styles ---------------------------
-trafford_flood_risk_styled <- trafford_flood_risk %>% 
+# Remove the previous files ---------------------------
+file.remove(c("trafford_flood_risk_styled.geojson",
+              "trafford_flood_risk_0_2m_depth_styled.geojson",
+              "trafford_flood_risk_0_3m_depth_styled.geojson",
+              "trafford_flood_risk_0_6m_depth_styled.geojson",
+              "trafford_flood_risk_0_9m_depth_styled.geojson",
+              "trafford_flood_risk_1_2m_depth_styled.geojson"))
+
+
+# Function to apply styles ---------------------------
+style_flood_risk <- function(unstyled_data_filename) {
+    read_sf(unstyled_data_filename) %>%
     mutate(stroke = case_when(
                         flood_risk == "Very low" ~ "#C4E1FF",
                         flood_risk == "Low" ~ "#A2CFFF",
                         flood_risk == "Medium" ~ "#6699CD",
                         flood_risk == "High" ~ "#3D4489",
-                        TRUE ~ "#ff0000"), # To visually indicate that something has gone wrong),
+                        TRUE ~ "#b1b3b4"), # Likely "Unavailable"
            `stroke-width` = 3,
            `stroke-opacity` = 1,
            fill = stroke,
            `fill-opacity` = 0.8)
+}
+
 
-# delete the old and then create the new data ---------------------------
-file.remove("trafford_flood_risk_styled.geojson")
-write_sf(trafford_flood_risk_styled, "trafford_flood_risk_styled.geojson")
+# Create the new styled data ---------------------------
+write_sf(style_flood_risk("trafford_flood_risk.geojson"), "trafford_flood_risk_styled.geojson", driver = "GeoJSON")
+write_sf(style_flood_risk("trafford_flood_risk_0_2m_depth.geojson"), "trafford_flood_risk_0_2m_depth_styled.geojson", driver = "GeoJSON")
+write_sf(style_flood_risk("trafford_flood_risk_0_3m_depth.geojson"), "trafford_flood_risk_0_3m_depth_styled.geojson", driver = "GeoJSON")
+write_sf(style_flood_risk("trafford_flood_risk_0_6m_depth.geojson"), "trafford_flood_risk_0_6m_depth_styled.geojson", driver = "GeoJSON")
+write_sf(style_flood_risk("trafford_flood_risk_0_9m_depth.geojson"), "trafford_flood_risk_0_9m_depth_styled.geojson", driver = "GeoJSON")
+write_sf(style_flood_risk("trafford_flood_risk_1_2m_depth.geojson"), "trafford_flood_risk_1_2m_depth_styled.geojson", driver = "GeoJSON")