the nhd and the future of stream mapping in west virginia evan fedorko west virginia gis technical...

The NHD and the Future of The NHD and the Future of Stream Mapping in West VirginiaStream Mapping in West Virginia

Evan FedorkoWest Virginia GIS Technical Centerwww.wvgis.wvu.edu

Jackie Strager (NRAC)www.nrac.wvu.edu

Kevin KuhnKurt Donaldson

WVGISTC

Introduction

• Outline:– Existing stream map: 24K NHD

• Issues with 24K NHD

– Current stream mapping: Local NHD• Pilot projects, results and future plans

– What’s next: Stewardship and the future of NHD• NHD successes and challenges

– Case study: Stream modifications in the Coal River

• Future of NHD

• Introduction• NHD 24K• NHD local• Stewardship

NHD Status in WV

• National Hydrography Dataset (NHD)• NHD is complete in WV for:

– Medium resolution (1:100,000 scale)– High resolution (1:24,000)

• Local resolution NHD (1:4,800) – Pilot projects complete– Gauley– Upper Guyandotte

• Introduction• NHD 24K• NHD local• Stewardship

Evaluating the NHD

• What could be improved in 24K NHD in WV?• How was this determined?

– Track known issues (NRAC)– Stream naming/coding process (NRAC/WVDEP)– Systematic statewide review by WVDEP– Case study: mining impacts in the Coal River

watershed (stewardship section)

• Introduction• NHD 24K• NHD local• Stewardship

Issues with 24K NHD

• Main Issues:– Errors in geometry– Errors in attributes– Errors in NHD formatting, reach coding– Changes in stream geometry since streams were

mapped

• Source data for 24K NHD:– 24K DLG data– Topo map blue lines– GNIS names

• Introduction• NHD 24K• NHD local• Stewardship

The big picture…• Introduction• NHD 24K• NHD local• Stewardship

Quantifying issues with the NHD

Primarily based on WVDEP review

The big picture…• Introduction• NHD 24K• NHD local• Stewardship

Quantifying issues with the NHD

Primarily based on WVDEP review

The big picture (2)…

Type of problemNumber of Segments

% of Segments

Total Length (mi)

Possible geometry error 614 0.28 254

NHD attribute error (FCODE) 6 0.00 3

Karst/sinking streams 291 0.13 107

NHD format error (reaches) 6 0.00 n/a

Name issues (possible) 204 0.09 89

Name issues 1,337 0.62 657

TOTAL 216,579 94,796

• Quantifying 24K NHD issues as identified by WVDEP review

• Introduction• NHD 24K• NHD local• Stewardship

Local resolution NHD

• Local streams mapped from 2003 SAMB aerial photography and 3m DEM

• Benefits:– Better cartographic base for local mapping– Captures changes in stream geometry, length

• Status:– Pilot projects complete for Gauley, Upper Guyandotte

watersheds in late 2008– Not currently downloadable from USGS

• Introduction• NHD 24K• NHD local• Stewardship

LR-NHD Conclusions• Introduction• NHD 24K• NHD local• Stewardship

• Two pilot watersheds completed – not available for download yet

• WV is the first state to complete conflation using USGS’ new (beta) conflation tools

• At this time, continued development of LR NHD is NOT recommended. Summary of reasons:– Issues with 1:4,800 scale source data – inconsistent collection

and inclusion of “special features” such as ditches and culverts– Comparative difficulty of conflation process– Propagation of HR-NHD errors– General lack of interest by the WV NHD community– The persistent generalization question– Continued changes in stream geometry

Future of NHD for WV…

• Goal: Establish a stewardship program for NHD in WV– Data updates– Ensures data maintenance– Central point of contact

• Steps taken: – Drafted a business plan for NHD in WV– Drafted an MOU between potential NHD steward and

the USGS– Working with potential NHD steward

• Introduction• NHD 24K• NHD local• Stewardship

Stewardship Status

• Successes– Completed business plan for NHD– Stakeholders have been engaged in an active

discussion– Survey conducted in 2008 revealed a great deal of

interest in establishing a stewardship program

• Introduction• NHD 24K• NHD local• Stewardship

Stewardship Status

• Challenges– Data policy issues within potential stewardship

agency– Community concerns over what scale of data will be

maintained – fear that preferred scale will be “left behind”

– Front loading of needed edits to HR-NHD resulting in initial…

– Challenge of funding and personnel commitment to NHD stewardship

• Introduction• NHD 24K• NHD local• Stewardship

Coal River case study

• Goal: Quantify amount of stream drainage change related to mining for southern WV watershed

• Input datasets:– 24K NHD stream lines– 1:4,800 local stream lines– 2003 SAMB aerial photos– 2007 NAIP aerial photos

• Introduction• NHD 24K• NHD local• Stewardship

Original 24K NHD• Introduction• NHD 24K• NHD local• Stewardship

2003 Aerial photos

2003Photo

• Introduction• NHD 24K• NHD local• Stewardship

Mining visible in 2003

2003Photo

• Introduction• NHD 24K• NHD local• Stewardship

Aerial photos 2007

2007Photo

• Introduction• NHD 24K• NHD local• Stewardship

Mining visible 2007

2007Photo

• Introduction• NHD 24K• NHD local• Stewardship

Summary for 24K NHD in Coal

Description Area (acres)

Length of 24K streams

(mi)

Entire Coal watershed 570,000 2,232

Impacted by mining (2003) 12,321 59

Impacted by newer mining (2007)

10,757 33

Coal case study: Local• Introduction• NHD 24K• NHD local• Stewardship

Coal case study: Local

Description Area (acres)

Length of streams

(mi)

Length of streams

(mi)

24K 1:4,800

Entire Coal watershed 570,000 2,232 2,829

Impacted by mining (2003) 12,321 59 n/a

Impacted by newer mining (2007)

10,757 33 38

• Introduction• NHD 24K• NHD local• Stewardship

Stewardship

• West Virginia’s next steps– Identify principal steward(s)– Consolidate key stakeholders and come to consensus

on key issues– Implement stewardship plan– Compile errors and begin editing

• Introduction• NHD 24K• NHD local• Stewardship

DiscussionNatural Resource Analysis CenterNatural Resource Analysis Center

West Virginia UniversityWest Virginia Universitywww.nrac.wvu.eduwww.nrac.wvu.edu

WV GIS Technical CenterWV GIS Technical CenterWest Virginia UniversityWest Virginia University

wvgis.wvu.eduwvgis.wvu.edu