Mapping Headwater Streams in North Carolina
Mapping Headwater Streams in North Carolina North Carolina Division of Water Quality North Carolina State University North Carolina Department of Transportation
10/1/2007
NC Water Quality
Background Problem: Existing Maps Inaccurate and Inconsistent Critical to NC Division of Water Quality 401 program and other public agencies and private sector Solution: Make better maps Take advantage of state-wide LiDAR (LIght Detection And Ranging) coverage
Tributaries shown on one map and not the other
Stream Mapping Project began early 2004 (NCDWQ, NCSU, NCDOT) 10/1/2007
NC Water Quality
Headwater stream shown on one map and not the other
Approach •Use LiDAR data acquired from the NC Floodplain Mapping Program to create new topographic maps •Conduct field identification and mapping of intermittent and perennial streams and their origins in headwater areas •Conduct spatial analysis using GIS data and field data •Use field data and other GIS data to create predictive models of streams and origins
10/1/2007
NC Water Quality
What are we trying to predict with spatial models? •Presence/Absence of stream in a valley •Stream length •Flow Duration –ephemeral, intermittent or perennial What are the influencing factors? What processes do these factors represent? How do factors and processes vary spatially?
10/1/2007
NC Water Quality
Methods: Field Data •Walk streams •Locate Origins •Determine flow regime (DWQ Stream ID, 2005 ) •GPS origins (sub-meter accuracy)
http://h2o.enr.state.nc.us/ncwetlands/regcert.html 10/1/2007
NC Water Quality
Methods: GIS Data Create Digital Elevation Models (DEMS) •Generate Terrain Derivatives •Acquire existing GIS Data, ex. Soils, geology… Spatial patterns and analysis 10/1/2007
NC Water Quality
•23 watersheds •600 + origins
10/1/2007
NC Water Quality
Little Creek, Yadkin Basin Stanley County, North Carolina
Streams Origins Intermittent Perennial Elevation (ft) High : 230
Low : 169
10/1/2007
NC Water Quality
Variables used (or to be used) in Analysis •Level IV Ecoregion •Local Slope •Average Slope •Contributing Drainage Area •Local Curvature, profile and plan •Average Upslope Curvature, profile and plan •Soils •Geology •Land use •Indices (roughness, stream power…)
10/1/2007
NC Water Quality
General Description Ephemeral to intermittent 46 % Intermittent to perennial 36 % Ephemeral to perennial (all mtns) 14 % Other, wetlands and modified 8% does not include outer coast First order intermittent stream length mountains 33 % piedmont 22 % inner coast plain 32 % outer coast plain 56 % 44 origins/1 site
10/1/2007
NC Water Quality
*Data for 21 sites, 542 origins
10/1/2007 0
NC Water Quality
0 .3
0 .2
0 .1
Coast Plain
Basin
0 .4
Basin
Perennial
Triassic
0 .6
Triassic
Coast Plain
0 .5
Rolling
Outer Piedmont
Northern
Ridge Foothills
Eastern Blue
Slate Belt-B
0 .4
Rolling
Outer Piedmont
Northern
Ridge Foothills
Eastern Blue
Slate Belt-B
Carolina
Slate Belt-A
0
Carolina
Between Ecoregions *Eastern Blue Ridge *Rolling Coastal Plain *Triassic Basin Carolina
Average Slope
Average Slope Int/Per Within Ecoregion *Eastern Blue Ridge
Slate Belt-A
Carolina
Average Slope
0 .5
Intermittent
0 .3
0 .2
0 .1
10/1/2007 0.1
Slate Belt-B
50 30
10
5 3
1
0.2
Perennial
Coast Plain
Rolling
Outer Piedmont
Basin
100
Basin
200
Triassic
400
Triassic
Coast Plain
0.5
Rolling
Outer Piedmont
Northern
Ridge Foothills
Eastern Blue
Slate Belt-B
Carolina
Slate Belt-A
Carolina
0.04
Northern
Ridge Foothills
Eastern Blue
NC Water Quality Carolina
Drainage Area (acres) 0.01
Slate Belt-A
Carolina
Between Ecoregions *Rolling Coastal Plain *Triassic & Eastern BR *Slate Belt & N. Outer Piedmont Drainage Area (acres)
Contributing
Contributing Drainage Area Int/Per Within Ecoregion All except Eastern Blue Ridge & Group B-Slate Belt
Contributing
300
100 40
10 4
0.4
1
0.1
Intermittent
0.35
0.3
Landscape Process….. Trend Plots Average Slope and Contributing Drainage Area against Topographic Relief by Site
Slope Range (ft/ft)
0.25
0.2
0.15
0.1
0.05
0
-0.05 20
30
40
50
70
100
200
300
400 500
700
relief (ft) 500
Range (max-min) Relief
Drainage Area
Relief
Drainage Area Range (acres)
Avg Slope
300 200
100 60 40 20
10 6 4 2
10/1/2007
1
NC Water Quality 20 30
40
50
70
100 relief (ft)
200
300
400 500
700
1000
Distribution of Intermittent and Perennial Origin Contributing Drainage Area (acres) Carolina Slate Belt-A
Carolina Slate Belt-B
Eastern Blue Ridge Foothills
Northern Outer Piedmont
Rolling Coastal Plain
Triassic Basin
int
per
int
per
int
per
int
per
int
per
int
per
Min
0.20
0.72
0.05
2.04
0.23
0.24
1.55
2.54
0.16
7.16
0.10
0.13
10%
1.47
7.53
0.77
2.39
2.17
1.02
1.80
4.07
7.52
10.76
1.24
1.89
25%
2.85
11.58
4.89
9.52
3.72
2.91
4.48
10.05
11.15
28.82
1.95
3.27
50%
7.36
15.99
23.80
37.50
4.60
4.98
8.82
16.18
25.67
84.00
3.70
6.85
Mean
11.20
23.74
50.86
60.85
5.16
5.27
12.72
20.52
40.66
95.59
5.11
10.40
75%
14.47
35.40
69.96
68.16
6.34
7.04
15.06
27.11
55.15
122.00
7.16
15.79
90%
27.39
43.33
142.41
187.26
8.16
9.81
22.99
41.31
101.33
217.34
11.87
27.80
Max
74.63
107.00
322.27
328.28
14.60
15.85
115.95
64.81
173.65
343.66
16.51
32.49
10/1/2007
NC Water Quality
Much to be Done!
10/1/2007
NC Water Quality
10/1/2007
NC Water Quality
Background Problem: Existing Maps Inaccurate and Inconsistent Critical to NC Division of Water Quality 401 program and other public agencies and private sector Solution: Make better maps Take advantage of state-wide LiDAR (LIght Detection And Ranging) coverage
Tributaries shown on one map and not the other
Stream Mapping Project began early 2004 (NCDWQ, NCSU, NCDOT) 10/1/2007
NC Water Quality
Headwater stream shown on one map and not the other
Approach •Use LiDAR data acquired from the NC Floodplain Mapping Program to create new topographic maps •Conduct field identification and mapping of intermittent and perennial streams and their origins in headwater areas •Conduct spatial analysis using GIS data and field data •Use field data and other GIS data to create predictive models of streams and origins
10/1/2007
NC Water Quality
What are we trying to predict with spatial models? •Presence/Absence of stream in a valley •Stream length •Flow Duration –ephemeral, intermittent or perennial What are the influencing factors? What processes do these factors represent? How do factors and processes vary spatially?
10/1/2007
NC Water Quality
Methods: Field Data •Walk streams •Locate Origins •Determine flow regime (DWQ Stream ID, 2005 ) •GPS origins (sub-meter accuracy)
http://h2o.enr.state.nc.us/ncwetlands/regcert.html 10/1/2007
NC Water Quality
Methods: GIS Data Create Digital Elevation Models (DEMS) •Generate Terrain Derivatives •Acquire existing GIS Data, ex. Soils, geology… Spatial patterns and analysis 10/1/2007
NC Water Quality
•23 watersheds •600 + origins
10/1/2007
NC Water Quality
Little Creek, Yadkin Basin Stanley County, North Carolina
Streams Origins Intermittent Perennial Elevation (ft) High : 230
Low : 169
10/1/2007
NC Water Quality
Variables used (or to be used) in Analysis •Level IV Ecoregion •Local Slope •Average Slope •Contributing Drainage Area •Local Curvature, profile and plan •Average Upslope Curvature, profile and plan •Soils •Geology •Land use •Indices (roughness, stream power…)
10/1/2007
NC Water Quality
General Description Ephemeral to intermittent 46 % Intermittent to perennial 36 % Ephemeral to perennial (all mtns) 14 % Other, wetlands and modified 8% does not include outer coast First order intermittent stream length mountains 33 % piedmont 22 % inner coast plain 32 % outer coast plain 56 % 44 origins/1 site
10/1/2007
NC Water Quality
*Data for 21 sites, 542 origins
10/1/2007 0
NC Water Quality
0 .3
0 .2
0 .1
Coast Plain
Basin
0 .4
Basin
Perennial
Triassic
0 .6
Triassic
Coast Plain
0 .5
Rolling
Outer Piedmont
Northern
Ridge Foothills
Eastern Blue
Slate Belt-B
0 .4
Rolling
Outer Piedmont
Northern
Ridge Foothills
Eastern Blue
Slate Belt-B
Carolina
Slate Belt-A
0
Carolina
Between Ecoregions *Eastern Blue Ridge *Rolling Coastal Plain *Triassic Basin Carolina
Average Slope
Average Slope Int/Per Within Ecoregion *Eastern Blue Ridge
Slate Belt-A
Carolina
Average Slope
0 .5
Intermittent
0 .3
0 .2
0 .1
10/1/2007 0.1
Slate Belt-B
50 30
10
5 3
1
0.2
Perennial
Coast Plain
Rolling
Outer Piedmont
Basin
100
Basin
200
Triassic
400
Triassic
Coast Plain
0.5
Rolling
Outer Piedmont
Northern
Ridge Foothills
Eastern Blue
Slate Belt-B
Carolina
Slate Belt-A
Carolina
0.04
Northern
Ridge Foothills
Eastern Blue
NC Water Quality Carolina
Drainage Area (acres) 0.01
Slate Belt-A
Carolina
Between Ecoregions *Rolling Coastal Plain *Triassic & Eastern BR *Slate Belt & N. Outer Piedmont Drainage Area (acres)
Contributing
Contributing Drainage Area Int/Per Within Ecoregion All except Eastern Blue Ridge & Group B-Slate Belt
Contributing
300
100 40
10 4
0.4
1
0.1
Intermittent
0.35
0.3
Landscape Process….. Trend Plots Average Slope and Contributing Drainage Area against Topographic Relief by Site
Slope Range (ft/ft)
0.25
0.2
0.15
0.1
0.05
0
-0.05 20
30
40
50
70
100
200
300
400 500
700
relief (ft) 500
Range (max-min) Relief
Drainage Area
Relief
Drainage Area Range (acres)
Avg Slope
300 200
100 60 40 20
10 6 4 2
10/1/2007
1
NC Water Quality 20 30
40
50
70
100 relief (ft)
200
300
400 500
700
1000
Distribution of Intermittent and Perennial Origin Contributing Drainage Area (acres) Carolina Slate Belt-A
Carolina Slate Belt-B
Eastern Blue Ridge Foothills
Northern Outer Piedmont
Rolling Coastal Plain
Triassic Basin
int
per
int
per
int
per
int
per
int
per
int
per
Min
0.20
0.72
0.05
2.04
0.23
0.24
1.55
2.54
0.16
7.16
0.10
0.13
10%
1.47
7.53
0.77
2.39
2.17
1.02
1.80
4.07
7.52
10.76
1.24
1.89
25%
2.85
11.58
4.89
9.52
3.72
2.91
4.48
10.05
11.15
28.82
1.95
3.27
50%
7.36
15.99
23.80
37.50
4.60
4.98
8.82
16.18
25.67
84.00
3.70
6.85
Mean
11.20
23.74
50.86
60.85
5.16
5.27
12.72
20.52
40.66
95.59
5.11
10.40
75%
14.47
35.40
69.96
68.16
6.34
7.04
15.06
27.11
55.15
122.00
7.16
15.79
90%
27.39
43.33
142.41
187.26
8.16
9.81
22.99
41.31
101.33
217.34
11.87
27.80
Max
74.63
107.00
322.27
328.28
14.60
15.85
115.95
64.81
173.65
343.66
16.51
32.49
10/1/2007
NC Water Quality
Much to be Done!
10/1/2007
NC Water Quality
