What This Library Is
The Allegheny DZ DB is a guide to the source layers that power the Allegheny County maps in this section of the site. Each numbered child page focuses on one source, explains what it shows in plain English, and pairs it with a readable example map.
This section is meant for people arriving cold. You do not need to know the database, the map system, or the project history beforehand. The goal is simple: make it easy to see what each source covers and why it matters.
Why These Sources Matter
No county map stands on a single layer. Parcels, streets, address points, municipal boundaries, parks, floodplains, rail lines, and hydrology all describe different parts of the same place. Taken together, they create a fuller picture of Allegheny County.
That is why this library exists. It gives each source its own page so the reader can understand the layer on its own terms before seeing how it fits into the wider county map set.
The Current Library
| Metric | Live value |
|---|---|
| Active numbered sources | 30 |
| Total rows across the source library | 3,506,705 |
| Mapped place pages | 219 |
| Layer-to-page matches across the site | 6,570 |
| Published map pages in the county section | 261 |
| DZ DB child pages in this section | 30 |
The figures above describe the current county source library: thirty numbered sources, hundreds of mapped places, and a published map system that draws from those layers across the site.
What Kinds Of Sources Are Here
| Source family | Examples | What they help explain |
|---|---|---|
| Places and boundaries | Address points, ZIP codes, municipalities, council districts, voting districts | How the county is divided, labeled, and located. |
| Land, streets, and buildings | Street centerlines, parcels, building footprints, landuse | How the built county is laid out on the ground. |
| Water, terrain, and landscape | Contours, hydrology lines, hydrology areas, basins, watersheds, wetlands, wooded areas, greenways | How water, slope, and natural systems shape the county. |
| Civic and public places | Parks, libraries, farmers markets, public buildings, pools, cemetery | Where everyday public destinations and shared spaces are located. |
| Risk and environmental conditions | Landslide layers, floodplain, natural heritage inventory | Where the county faces risk, constraint, or ecological sensitivity. |
Source Catalog
The catalog below is the active source library for this section. It shows what each numbered source covers, how large it is, and how widely it appears across the county map pages.
| # | Source | What it covers | Rows | Fields | Public coverage | Source system |
|---|---|---|---|---|---|---|
| 001 | Address Points | Master county address point inventory used for address search, place-level counts, and the raw point layer in the public explorer. | 653,615 | 33 + geometry | 219 / 219 | WPRDC CKAN package allegheny-county-addressing-address-points2; geometry from PASDA layer 32 |
| 002 | Street Centerlines | County street centerline geometry with street names, range fields, ZIP edge fields, and left/right municipality references. | 82,265 | 42 + geometry | 219 / 219 | PASDA MapServer layer 7 |
| 003 | Parcels | County parcel polygons with parcel identifiers, municipal codes, and acreage fields for ownership-sized land units. | 586,120 | 12 + geometry | 219 / 219 | PASDA MapServer layer 25 |
| 004 | Building Footprints | Building polygon outlines with classification and change-related fields from the county PASDA layer. | 588,094 | 10 + geometry | 219 / 219 | PASDA MapServer layer 11 |
| 005 | ZIP Code Boundaries | ZIP boundary polygons with county and residential/business count fields from the county ZIP boundary source. | 127 | 23 + geometry | 219 / 219 | PASDA MapServer layer 33 |
| 006 | Municipal Boundaries | Allegheny County municipal polygons with labels, COG, school district, region, FIPS, acreage, and square-mile fields. | 130 | 22 + geometry | 219 / 219 | PASDA MapServer layer 21 |
| 007 | Farmers Markets | Point inventory of county farmers markets with names, addresses, schedule text, and season notes. | 54 | 11 + geometry | 47 / 219 | PASDA MapServer layer 36 |
| 008 | Landslides Individual Assistance | Point records for landslide assistance cases with contact, location, owner/renter, and damage-related fields. | 36 | 15 + geometry | 21 / 219 | PASDA MapServer layer 39 |
| 009 | Parks | Park polygons with names, addresses, image links, and last-update fields from the county parks source. | 10 | 14 + geometry | 21 / 219 | PASDA MapServer layer 24 |
| 010 | Voting Districts | Voting district and ward polygons with municipality and district code fields used for election-adjacent geography. | 1,327 | 16 + geometry | 219 / 219 | PASDA MapServer layer 28 |
| 011 | Landslide Prone | Polygon layer marking mapped landslide-prone areas with acreage, square-mile, and code fields. | 37 | 12 + geometry | 114 / 219 | PASDA MapServer layer 37 |
| 012 | Landslides County Public Works | County Public Works landslide records with road number, project number, municipality, restriction, and remediation fields. | 115 | 12 + geometry | 45 / 219 | PASDA MapServer layer 38 |
| 013 | Landslides Public Assistance | Point records for public assistance landslide cases with agency, type, category, and damage-value fields. | 86 | 16 + geometry | 58 / 219 | PASDA MapServer layer 40 |
| 014 | Public Buildings | Public building facilities with class, facility name, address, phone, and municipal code fields. | 253 | 17 + geometry | 161 / 219 | PASDA MapServer layer 1 |
| 015 | Libraries | Library facilities with service area, use, address, and contact fields. | 63 | 14 + geometry | 62 / 219 | PASDA MapServer layer 0 |
| 016 | Contours | Elevation contour lines with feature codes and elevation values from the county contour layer. | 1,464,242 | 6 + geometry | 120 / 219 | PASDA MapServer layer 2 |
| 017 | Hydrology Lines | Hydrology linework for streams and drainage channels with feature codes and update-year fields. | 26,720 | 5 + geometry | 206 / 219 | PASDA MapServer layer 3 |
| 018 | Railroad Lines | Railroad linework with system, user, and feature code fields from the county rail source. | 10,819 | 6 + geometry | 193 / 219 | PASDA MapServer layer 6 |
| 019 | Basins | Drainage basin polygons with basin, subclass, symbol, and direction fields. | 18 | 17 + geometry | 187 / 219 | PASDA MapServer layer 9 |
| 020 | Cemetery | Cemetery polygons with names, addresses, acreage, and shape-area fields. | 261 | 14 + geometry | 155 / 219 | PASDA MapServer layer 12 |
| 021 | Council Districts | Allegheny County council district polygons with district label fields. | 13 | 6 + geometry | 219 / 219 | PASDA MapServer layer 14 |
| 022 | Floodplain | Floodplain polygons with floodplain and map-type fields for mapped flood-risk areas. | 502 | 9 + geometry | 219 / 219 | PASDA MapServer layer 15 |
| 023 | Greenways | Greenway features with type and status fields representing county open-space corridors. | 53,034 | 6 + geometry | 219 / 219 | PASDA MapServer layer 17 |
| 024 | Hydrology Areas | Hydrology polygons with hydro code fields for waterbody and area-style hydrologic features. | 1,439 | 9 + geometry | 219 / 219 | PASDA MapServer layer 18 |
| 025 | Landuse | Coded land-use or land-cover polygons with feature-code and update-year fields from the county land-use layer. | 21,520 | 8 + geometry | 218 / 219 | PASDA MapServer layer 20 |
| 026 | Natural Heritage Inventory | Natural Heritage Inventory polygons with type, name, acreage, and rank fields. | 37 | 11 + geometry | 123 / 219 | PASDA MapServer layer 22 |
| 027 | National Wetlands Inventory | Wetland polygons with wetland classification fields from the National Wetlands Inventory layer. | 777 | 8 + geometry | 106 / 219 | PASDA MapServer layer 23 |
| 028 | Pools | Pool facility features with names, addresses, phone numbers, and pool count fields. | 179 | 14 + geometry | 109 / 219 | PASDA MapServer layer 26 |
| 029 | Watersheds | Watershed polygons with descriptive and count fields representing larger drainage catchments. | 138 | 11 + geometry | 219 / 219 | PASDA MapServer layer 29 |
| 030 | Wooded Areas | Woodland polygons with nature code, acreage, and shape-area fields from the county wooded-areas source. | 14,674 | 10 + geometry | 217 / 219 | PASDA MapServer layer 31 |