The NHD and the Future of Stream Mapping in West Virginia

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The NHD and the Future of
Stream Mapping in West Virginia
Evan Fedorko
West Virginia GIS Technical Center
www.wvgis.wvu.edu
Jackie Strager
Natural Resource Analysis Center
www.nrac.wvu.edu
Introduction
• Outline:
– History of NHD Development in West Virginia
• Overview of NHD status in WV
• Local Resolution NHD Pilot Projects
– Existing stream map: 24K NHD
• Known issues
• Need for upgrades/stewardship
– What’s next: Stewardship and the future of NHD
• Challenges
• The Plan
• How YOU can help!
• Introduction
• Current NHD
• 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
• Current NHD
• Stewardship
Local resolution NHD
• Introduction
• Current NHD
• Stewardship
• 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
LR-NHD Conclusions
• Introduction
• Current NHD
• Stewardship
• Two pilot watersheds completed
• WV one of the first states to complete conflation
using USGS’ new conflation tools
• At this time, continued development of LR-NHD
is not recommended. Reasons:
– Issues with 1:4,800 source data – inconsistent 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
Evaluating the NHD
• Introduction
• Current NHD
• Stewardship
• At this time, most complete statewide stream
dataset is the 24K NHD (HR-NHD)
• What can be improved in 24K NHD in WV?
• Evaluation of the 24K NHD
– Statewide review by WVDEP
– Documentation of errors by NRAC, WVDEP
– Case study of mining-related changes (Coal River)
Issues with 24K NHD
• Introduction
• Current NHD
• Stewardship
• 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
Issues with NHD: Source data
NHD Source data:
USGS Topo maps
• Introduction
• Current NHD
• Stewardship
Issues with NHD
Quantifying issues
with the NHD
Primarily based on
WVDEP review
• Introduction
• Current NHD
• Stewardship
Issues with NHD
Quantifying issues
with the NHD
Primarily based on
WVDEP review
• Introduction
• Current NHD
• Stewardship
• Introduction
• Current NHD
• Stewardship
Quantifying issues
• Quantifying 24K NHD issues as identified by
WVDEP review
Type of problem
Possible geometry error
NHD attribute error (FCODE)
Karst/sinking streams
NHD format error (reaches)
Name issues (possible)
Name issues
TOTAL
Number of
Segments
% of
Segments
Total Length
(mi)
614
0.28
254
6
0.00
3
291
0.13
107
6
0.00
n/a
204
0.09
89
1,337
0.62
657
216,579
94,796
Geometry issues in NHD
• Stream updates needed due to:
• Construction of dams, impoundments
• Roads, highways
• Ongoing mining-related alterations
• Introduction
• Current NHD
• 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
• Current NHD
• Stewardship
Original 24K NHD
• Introduction
• Current NHD
• Stewardship
• Introduction
• Current NHD
• Stewardship
2003 Aerial photos
2003
Photo
• Introduction
• Current NHD
• Stewardship
Mining visible in 2003
2003
Photo
• Introduction
• Current NHD
• Stewardship
Aerial photos 2007
2007
Photo
• Introduction
• Current NHD
• Stewardship
Mining visible 2007
2007
Photo
Summary for 24K NHD in Coal
Description
Entire Coal watershed
Impacted by mining (2003)
Impacted by newer mining
(2007)
Area
(acres)
Length of
24K streams
(mi)
570,000
2,232
12,321
10,757
59
33
Total: 4.1% of stream length
NOTE: Similar analysis shows that 1.3% of mapped
local scale streams were impacted by mining
between 2003 and 2007.
Future of NHD for WV
• Introduction
• Current NHD
• Stewardship
• Goal: Establish a stewardship program for NHD
in WV, including:
– Ensure data updates and maintenance (immediate &
long-term)
– Develop procedures & policies
– Identify principal steward, technical lead, substewards, et al.
• Steps taken so far:
– Drafted a business plan for NHD in WV
– Drafted an MOU between potential NHD steward and
the USGS
– Drafted a tentative plan – debuting today!
Business Plan
• Introduction
• Current NHD
• Stewardship
• Completed business plan for NHD in WV
• Business plan includes:
–
–
–
–
–
History of the NHD
Local Resolution Development
Current uses/users of NHD in WV
A plan for NHD stewardship in WV
A draft memorandum of understanding between the
USGS and a stewardship entity
Plan (1)
• Introduction
• Current NHD
• Stewardship
• Identify the principal NHD steward for West
Virginia
– MOU Signatory: WV Office of GIS State Coordination,
Tony Simental
• Responsibilities of the principal steward:
– Sign MOU with USGS
– Work with Technical Coordinator and Sub-Stewards
to lead, fund and maintain an NHD Stewardship
program
Plan (2)
• Introduction
• Current NHD
• Stewardship
• Identify the Technical Lead of NHD Stewardship
for West Virginia:
– West Virginia GIS Technical Center
• Responsibilities of Technical Lead:
– Trained to use USGS NHD Geo Edit tools – actively
edits the NHD
– Leads and coordinates stewardship efforts
– Acts as the principal authority on stewardship issues
– Coordinates sub-stewards and works to ensure best
available knowledge is utilized to improve the NHD
Plan (3)
• Identify a core group of sub-stewards
– Candidates: Natural Resource Analysis Center, WV
Department of Natural Resources, USFS – Mon
National Forest, WVDEP – Office of Water
Resources, et al.
• Responsibilities of sub-stewards:
– Trained to use USGS NHD Geo Edit tools
– May participate in editing of NHD data
– Fill in knowledge gaps
Plan (4)
• Introduction
• Current NHD
• Stewardship
• Work as a group with the NSDI and NHD
liaisons to secure start up funding for NHD
Stewardship
• Tentative Plan:
– WVGISTC and NRAC joint project with the goal of
editing the NHD beginning with known errors (Slide
#9)
– Will also include analyzing HR-NHD lines and FEMA
DFIRM flood zones and editing geometry (extent
TBD)
– Plan for the future: addressing the changes to hydro
features in the coalfields
Plan (5)
• Introduction
• Current NHD
• Stewardship
• Develop a coordination framework for editing the
NHD; emphasize:
– Organized editing
– Information sharing
• Schedule an onsite NHD Geo Edit training
session
– At a minimum, technical lead and sub-stewards will
participate
Plan (6)
• Introduction
• Current NHD
• Stewardship
• Convene a hydrographic data users group
• Some suggested tasks and topics:
– Develop a “best practices” document for NHD use
within groups or agencies
– Explore, document and promote NHD tools and
software such as the Hydro Event Management Tool
(HEM)
– Identify and discuss NHD stewardship policy issues
Plan (7)
• Introduction
• Current NHD
• Stewardship
• Continue and expand the compilation of known
errors to the NHD
• Develop a methodology to receive potential edits
from stewardship community, such as a web
editing or web based problem reporting tool.
– Several states have deployed or are developing
similar tools; Vermont, Alabama, Texas, et al.
Discussion
Natural Resource Analysis Center
West Virginia University
www.nrac.wvu.edu
WV GIS Technical Center
West Virginia University
wvgis.wvu.edu
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