1. 8-Digit HUC Watershed Prioritization in Arkansas - Risk Assessment Matrix Approach
2010 Updates
Dharmendra Saraswat & Tom Riley
ANRC Task Force Meeting, September 21, 2010

2. Arkansas embarked on developing a proactive stakeholder process
Arkansas Approach
Arkansas embarked on developing a proactive stakeholder process
A comparative risk assessment based collaborative process that integrate scientific analysis and stakeholder deliberation
ANRC Task Force Meeting, September 21, 2010

3. Goal Select a few watersheds for priority implementation
Priority watersheds eligible for 319(h) incremental funding
Target known water quality impairments
Effectively allocate resources
ANRC Task Force Meeting, September 21, 2010

4. Process ANRC Task Force Meeting, September 21, 2010 2005-2009 Plan
2008 Revision
Sl#
Approved category 1
Water Body impairment 2
Human Health Impact 3
Biotic Impacts 4
Potential Human Exposure 5
Construction 6
Rural Roads 7
Non-row Crop Agriculture 8
Row Crop Agriculture 9
Urban 10
Forestry 11
Priority of a Bordering State
Water Body Impairment
2. Designated Use Impact
3. Biotic Impacts
4. Potential Human Exposure
5. Urban and Suburban Population
6. Impervious Surface
7. Economic Activity
8. Cropland
9. Livestock and Pasture
10. Unpaved Roads
11. Forestry
12. Priority of Neighboring State
ANRC Task Force Meeting, September 21, 2010

5. 1. Water Body Impairment ANRC Task Force Meeting, September 21, 2010
Category Definition
Category Definition 5a
Truly impaired; develop a TMDL or other corrective action(s) for the listed parameter
High
Truly impaired; develop a TMDL or other correction action(s) for the listed parameter(s). 5b
Waters currently not attaining standards, but may be de-listed with future revisions to Regulation No. 2, the state water quality standards;
Medium
Waters currently not attaining standards, but may be de-listed with future revisions to Regulation No. 2, the state water quality standards; or
Waters which are impaired by point source discharges and future permit restrictions are expected to correct the problem(s). 5c
Waters in which the data is questionable because of QA/QC procedures and which require confirmation before a TMDL is scheduled; 5d
Waters which need data verification to confirm use impairment (additional sampling, biological assessment) before a TMDL is scheduled;
Low
Waters currently not attaining one or more water quality standards, but all designated uses are determined to be supported; or
There is insufficient data to make a scientifically defensible decision concerning designated use attainment; or
Waters ADEQ assessed as unimpaired, but were added to the list by EPA. 5e
Waters which are impaired by point source discharges and future permits restrictions are expected to correct the problem; 5f
These are waters that are not currently meeting a water quality standard. However, “the basis for not meeting an applicable water quality standard is not caused by a pollutant, but is attributed to other types of pollution” (EPA, 2005). 5g
Water bodies added to ADEQ’s list of Impaired Water bodies by EPA.
2008
2009
ANRC Task Force Meeting, September 21, 2010

6. 2. Designated Use Impact - implementation
Working Definition
Score
Watersheds with at least one water body in (d) list Category 4a & 5a* not supporting aquatic life 10
Watersheds with at least one water body in (d) list Category 4a & 5a* not supporting primary and secondary contact 9
Watersheds with at least one water body in (d) list Category 4a & 5a* not supporting drinking 8
Watersheds with at least one ESW, available on geostor 5
Watersheds with at least one ERW, available on geostor 4
Watersheds with at least one water body in (d) list Category 4a & 5a* not supporting agricultural/industrial use 2
*Ignore those with source “MP”
ANRC Task Force Meeting, September 21, 2010

7. 3. Biotic Impact - implementation
Working Definition
Score
Watersheds with at least one water body in (d) list Category 4a & 5a not supporting aquatic life* 10
Watersheds with at least one water body in (d) list Category 4a & 5a with siltation (SI) listed as the cause*
Watersheds with at least one water body in (d) list Category 4a & 5a with dissolved oxygen (DO) listed as the cause* 9
Watersheds with at least one water body in (d) list Category 4a & 5a with nutrients (NU), nitrate (NO3), or phosphorous (P) listed as the cause* 8
Watersheds with at least one water body in (d) list Category 4a & 5a with ammonia (AM) listed as the cause* 4
ANRC Task Force Meeting, September 21, 2010

8. 4. Potential Human Exposure
Proposed Criteria
Score
Tributary to a public surface water supply 10
Tributary to or part of a recreational lake 8
Natural & scenic river or urban stream
All other waters 2
ANRC Task Force Meeting, September 21, 2010

9. 5. Urban/Suburban Population
Percentile rank of population density of urban and suburban area
Score = Percentile rank x 10
ANRC Task Force Meeting, September 21, 2010

10. 6. Impervious Surface 2006 Land Use/Land Cover
Estimate percentage of pervious surface
Calculate percentile rank
Score = percentile rank x 10
ANRC Task Force Meeting, September 21, 2010

11. 7. Economic Activity Proposed Criteria Score
Change in construction activity 5
Shale development- with atleast one active natural gas permit 4
Other economic activity- atleast one mining activity pemit 2
Change to 1
ANRC Task Force Meeting, September 21, 2010

12. 8. Cropland - implementation
Acreage of harvested area for each county from 2007 USDA agriculture census*
Watershed acreage based on area weighting
Calculate percentile of watershed harvested cropland density
Score = percentile x10 *
ANRC Task Force Meeting, September 21, 2010

13. 9. Livestock & Pasture Percentile rank of density of animal units x 5
Percentile rank of density of pasture x 5
Score = Livestock + Pasture
ANRC Task Force Meeting, September 21, 2010

14. 10. Unpaved Roads - implementation
Calculate length of un-paved roads for each watershed using the AHTD Roads GIS layer*
Calculate percentile rank of density of unpaved roads for each watershed
Score = Percentile rank x 10
* Arkansas State Highway and Transportation Department/GeoStor
ANRC Task Force Meeting, September 21, 2010

15. 11. Forestry
2009 recommendation
Density of public, state, and private forest land in each watershed in 2006*
Calculate percentile rank for public and private forests
Score = State Forest x 2 + Public Forest x 3 + Private Forest x 5
*CAST/GeoStor
ANRC Task Force Meeting, September 21, 2010

16. 12. Priority of Neighboring State
ANRC Task Force Meeting, September 21, 2010

17. ( ) Arkansas Approach – Steps Used in 2010 Matrix X Final Score =
Assign Score for Each Category
Final Score = 3 4 8 10 2 6 5 1 7 9
Overlay 3 4 8 10 2 6 5 1 7 9 3 4 8 10 2 6 5 1 7 9 3 4 8 10 2 6 5 1 7 9 X
1. Water Impairment
1. Water Impairment (
2. Use Impact
3. Biotic Impact
4. Human Exposure 3 4 8 10 2 6 5 1 7 9
5. Urban/Suburban Population
2. Use Impact
6. Impervious Surface
7. Economic Activity
8. Cropland 10
9. Livestock & Pasture
10. Unpaved Roads
12. Neighboring State Priority 10
11. Forestry )
12. Neighbor’s Priority
ANRC Task Force Meeting, September 21, 2010

18. Priority Map
ANRC Task Force Meeting, September 21, 2010

19. Priority Watersheds ANRC Task Force Meeting, September 21, 2010
Subwatershed Name
HUC (8-digit)
Drainage Area (km2)
Majority Land Use
Final Risk Matrix Percentile
Beaver Reservoir
Forest (64%)
100
Poteau
Forest (61%) 98
Bayou Bartholomew
Forest (59%) 97
Illinois
Pasture (45%) 95
Ouachita Headwaters
Forest (77%) 93
Lake Conway-Point Remove
Forest (54%) 91
Upper Ouachita
Forest (79%) 90
Upper Saline
Forest (78%) 88
L Anguille
Crops (71%) 85
Cache
Crops (67%)
Strawberry
Forest (58%) 83
Lower Ouachita-Smackover
Forest (82%) 81
ANRC Task Force Meeting, September 21, 2010

20. Risk Matrix Summary ANRC Task Force Meeting, September 21, 2010
Watershed
HUC 8 digit C1 C2 C3 C4 C5 C6 C7 C8 C9
C10
C11
C12
Total
Beaver Reservoir 10
8.28
5.69
7.93
4.14
8.79
2.76
6.31
838.97
Poteau
8.62
9.22
2.41
4.31
5.86
3.45
725.00
Bayou Bartholomew 8
3.62
2.47
6.72
4.05
7.41
707.24
Illinois 5
9.31
9.66
9.91
5.34
8.10
8.45
5.52
650.34
Ouachita Headwaters
7.24
5.14
0.86
3.19
5.57
640.69
Lake Conway-Point Remove
9.14
9.48
5.17
6.55
620.69
Upper Ouachita
3.97
6.03
4.53
0.69
1.72
6.78
616.55
Upper Saline
5.31
1.90
5.97
566.07
Cache 4 2
3.79
6.90
8.97
2.16
7.59
564.31
L Anguille
4.83
5.00
3.07
1.38
3.60
Strawberry
3.28
4.91
555.34
Lower Ouachita-Smackover
2.07
6.29
0.34
7.12
546.90
*C1 = Water body impairment, C2 = Designated usage, C3 = Biotic impact, C4 = Potential human impact, C5 = Urban suburban population,
C6 = Impervious surface, C7 = Economic activity, C8 = Cropland, C9 = Livestock and pasture, C10 = Unpaved roads, C11 = Forestry,
C12 = Adjacent state priority
ANRC Task Force Meeting, September 21, 2010

21. Selected Priority Watersheds
Name
HUC 8 Digit
Name of impaired streams/segments
Causes for impairment*
Source
Ouachita Headwaters
Marzam Creek pH
NO T SPECIFIED
Little Marzam Creek UN
Prairie Creek
DO, Cu, Tb SE
Upper Ouachita
Cove Creek
pH, SO4, TDS
RE, UN
Chamberlain Creek
pH, SO4, TDS, Cu, Zn, Cd RE
Lucinda Creek
pH, SO4, Zn
D.C. Creek Zn
Caddo River
Tb, Zn
Ouachita River
Deceiper Creek
Freeo Creek
White Oak Creek
Tulip Creek
Cypress Creek
S. Fork Caddo
Cu, Zn
ANRC Task Force Meeting, September 21, 2010

22. Selected Priority Watersheds
Name
HUC 8 Digit
Name of impaired streams/segments
Causes for impairment*
Source
Cache
Cache River
TDS, Pb, Tb AG
Frierson Lake
Sl, Cu UN
Old Town NU
Bayou DeView
Cl, TDS, Pb
IP, MP, AG
Lost Creek Ditch Cl
Strawberry
Strawberry River
Tb, PA SE
Lower Ouachita-Smackover
Moro Creek
Cu, Pb, Tb, Hg
UN, SE
Ouachita River
Cu, Zn, Hg
L. Champagnolle Cr. Hg
Champagnolle
Elcc Tributary
Cu, Zn, NO3, Cl, SO4, TDS, AM IP
Flat Creek
Cu, Zn, Cl, SO4, TDS
RE, IP
Salt Creek
pH, Cu, Cl, TDS
Prairie Creek Tb
Smackover Creek
DO, Zn
Jug Creek Cu MP
ANRC Task Force Meeting, September 21, 2010

23. Questions/Discussions
ANRC Task Force Meeting, September 21, 2010