Twenty-two NCDOT layers. One map.

One public folder

Where the data lives

Every layer is a map image layer drawn by the NCDOT ArcGIS Server from the public NCDOTApp_ESM folder — ESM is NCDOT’s Environmental Sensitivity Map, the online map its planners and engineers use to see streams, wetlands and other sensitive sites near a project. The folder lists 32 map services; the app uses 22, and the View REST Service link on each card opens that service’s own page.

A map image layer means the server draws the picture: the browser asks for an image of the current view and the server sends one back, so every pan or zoom redraws a moment after the map stops.

• NCDOTApp_ESM folder — the public folder on the NCDOT ArcGIS Server that every layer is drawn from.
• NCDOT — the agency that publishes the services.

Watch it work

Watch the walkthrough

The four tabs, the scale windows and Zoom to Make Visible, stream popups on Jordan Lake, the 303(d) layer and its legend, HUC watersheds with opacity, the statewide layers, and the landmarks, basemaps and Scale & Extent tools.

How it works

Four tabs, twenty-two layers

Streams

Two 24K stream networks (2006 and 2014), impaired streams and implicit outfalls. The 2006 network was developed by the North Carolina Center for Geographic Information and Analysis with the former NC Division of Water Quality, now part of the NC Division of Water Resources, and draws from about 1:144,000.

Watersheds

Hydrologic Unit Code boundaries HUC-12 and HUC-14, the Jordan, Falls, High Rock and Goose Creek watersheds, a Catawba main-stem buffer and USGS drainage areas. HUC-12 draws from 1:500,000; HUC-14 is a separate Natural Resources Conservation Service delineation, not a finer split of HUC-12. Watershed fills have an opacity slider.

Quality

The 2014 303(d) impaired streams — North Carolina’s Integrated Report, submitted to EPA by the Division of Water Resources; Category 5 is the 303(d) list itself, where a TMDL is required — plus two trout layers, FEMA stream study types and critical areas. The lists are resubmitted every two years, so the layer is a baseline, not today’s list.

Context

Eco-regions, ESM regions, CAMA counties (the twenty coastal counties), spill basin boundaries and lines, and stormwater controls.

Scale windows

Each layer draws only inside its own scale window, printed on the Zoom to Make Visible button; click it and the map zooms to a view where the layer can draw. Layers without a limit read Visible at all scales. Implicit outfalls draw from 1:200,000, FEMA study types from 1:300,000, the DWR trout layer from 1:10,000,000.

Popups and legends

Click a stream for its attributes straight from the service — assessment unit, water supply classification, river basin — and page through the features under one click. Expand a card for its legend, pulled from the service’s own REST legend endpoint.

Getting around

Landmarks (five fixed views, from the State Capitol to the Cape Hatteras Lighthouse), nine basemaps, eleven preset scales, and Scale & Extent for the current scale, zoom level and extent, each with a Copy button. The info button opens About (the use notice) and How to Use.

Limits

What it does not do

• It is not an NCDOT product. The data is NCDOT’s; the map and the app are All Things Spatial’s. The About tab carries NCDOT’s use notice: for information and planning only, with questions to the NCDOT GIS help desk.
• The 303(d) layer is the 2014 Integrated Report as published in the service, not the current list.
• Nothing is cached or stored: every layer is drawn live by the NCDOT server, so a service outage shows as a layer that does not draw.

FAQ

Common questions

Why does a layer show nothing when I switch it on?

It is outside its scale window. The window is printed on the card’s Zoom to Make Visible button; click it.

Where does the legend come from?

From each service’s own REST legend endpoint, so it matches what the server draws.

Can I use these services in my own map?

Yes — every card’s View REST Service link opens the public service page, and a map image layer takes that URL directly.

Is HUC-14 a finer HUC-12?

No. It is a separate NRCS delineation in the NCDOT folder.

Is the code available?

The app is a demonstration built with TypeScript and React on the ArcGIS Maps SDK for JavaScript, styled with Tailwind, built with Vite; the patterns are the ones All Things Spatial builds for clients.