Incorporating the US National Grid into Map Products

Incorporating the US National Grid into Map Products Randy Knippel Dakota County

United States National Grid (USNG) • National standard since 2001 • Adopted by federal agencies – FEMA, DHS, NGA, USGS • Adopted by several states – Florida, Missouri, North Carolina, others – Minnesota (March 25, 2009) • Military Grid Referencing System • Interoperable with UTM

Grid Zone Designation (GZD) 6 x 8 Degrees

100 Km Squares

10 Km Squares USNG: 15 T VK 75 UTM: Zone 15 N 470, 000 E 4, 950, 000 N

1 Km Squares USNG: 15 T VK 7857 UTM: Zone 15 N 478, 000 E 4, 957, 000 N

Why? • Multiple grids – Needed one for everyone • Need efficient location referencing • Need interoperability – Across jurisdictions – Local, state, federal, military

What about Lat / Long? • Not intuitive – Degrees, minutes, seconds • Several formats – DMS, DMS. sss, DM. mmm, D. ddd – Longitude • • • +/West / east Increases right to left

What about Lat / Long? • How big is a degree? – It varies • • • 69 miles at the equator Longitude gets smaller toward poles 50 miles in Dakota County • Distance calculations are difficult

Scalable National Regional Local

Precision and Truncation • 18 SUJ 2337106519 – 18 S UJ 23371 06519 • 1 meter precision, full USNG designation – UJ 2306 • • • Assume GZD (18 S) UJ – 100, 000 m precision (100 km square) 23 06 – 1000 m precision (1 km square) – 2337 0651 • 10 m precision • Assume GZD and 100 km square

Truncating GZD USNG: 15 T VK (100 Km square) ØVK is unique for 800 miles in any direction

Critical Infrastructure Key Resources Vulnerable Population

GIS For Emergency Management • Damage assessment • Status • Resource deployment • Planning • Analysis

Maps!

Fire Map Book

Map Index

Map 7456 (15 T VK 74 56)

Street Index Dana Dr.

Map VK 75 7456

Map 7456 (15 T VK 74 56) 741565 (15 T VK 741 565)

Deployment • • • Maps and map books on the web Printed maps and map books Strategic distribution Train the trainer Training Dispatch

Red River Flood 100 K 1 K

Statewide Effort • Create 10 K maps for entire state – FGDC CAP grant – Structures & data stewardship • Engage locals to verify data • Develop data, templates, procedures – File naming convention

Merge PDF’s • For each USNG pdf file in the overlay directory: – Find the corresponding USNG pdf file in the basemap directory – Merge the overlay pdf and legend pdf file into the basemap pdf – Write the output pdf to a new directory using a date / time stamp

Merge PDF’s • Adobe Acrobat – Standard Edition – Watermark (with transparency!) • Adobe Acrobat – Pro Edition – Scripting • Python Scripting – Py. PDF – Batch processing • Others…

Python Script Using Py. PDF from py. Pdf import Pdf. File. Writer, Pdf. File. Reader output = Pdf. File. Writer() basemap = Pdf. File. Reader(file("basemap15 TVK 85. pdf", "rb")) overlay = Pdf. File. Reader(file("event 115 TVK 85. pdf", "rb")) legend = Pdf. File. Reader(file("event 1legend. pdf", "rb")) result = input 1. get. Page(0) result. merge. Page(overlay. get. Page(0)) result. merge. Page(legend. get. Page(0)) output. add. Page(result) output. write(file("20091208132215 TVK 85. pdf", "wb")) output. Stream. close()

Special Case At GZD Boundaries

USNG Field Names

We Need Your Help! • Study USNG standard and materials • Provide peer review – USNG data – Field names – Template MXD’s – 10 K maps • Develop standard procedures & scripts • Sell it!