20130927Nutrients_Modeling_Update_-_Wade_Cantrell,_SCDHEC

Lower Catawba Basin
Nutrient TMDL Update
Lower
Catawba
Basin
Background
• History of nutrient overload
• Effects expressed in SC lakes
– Impaired water quality: Phosphorus, Nitrogen, Chlorophyll, pH,
Dissolved Oxygen
– Increased DO depletion in bottom waters
• Water quality management concern since at least 1990s
– Modeling studies (Duke, USC, SCDHEC, NCDWQ, et al.)
– SC numeric nutrient criteria (2001)
– NPDES permitting
• SCDHEC begins limiting Phosphorus in permits (2001)
• Settlement agreement SCDHEC, NCDWQ, Charlotte (2002)
• NC NPDES Phosphorus load reductions (2006)
Background (cont.)
• SCDHEC TMDL effort
– Additional modeling, stakeholder meetings, model
review, technical comments (2005-2008)
– TMDL development paused
• Other projects
• System changing/model updates needed
• Declining resources
Total Phosphorus Loads Discharged into Lower Catawba Basin - Fishing Creek
Reservoir from Major NC & SC Dischargers
0
200
400
600
800
1000
1200
1/1/1998 1/1/2000 1/1/2002 1/1/2004 1/1/2006 1/1/2008 1/1/2010 1/1/2012 1/1/2014
Date
TP

(
k
g
/
d
a
y
)
NC Total
SC Total
Total Phosphorus Concentrations in Fishing Creek Reservoir at SC-9 and at
Dam
0.00
0.10
0.20
0.30
0.40
0.50
0.60
1/1/1998 1/1/2000 1/1/2002 1/1/2004 1/1/2006 1/1/2008 1/1/2010 1/1/2012 1/1/2014
Date
TP

(
m
g
/
L
)
SC-9
Dam
Lake Standard
TP Standard
0.84
Total Phosphorus Concentrations in Lake Wateree at Headwater (Cedar Creek
Reservoir TR) and at Dam
0.00
0.05
0.10
0.15
0.20
0.25
0.30
1/1/2002 1/1/2004 1/1/2006 1/1/2008 1/1/2010 1/1/2012 1/1/2014
Date
TP

(
m
g
/
L
)
Dam
Headwater
Lake Standard
TP Standard
303(d) List of Impaired Waters
• 2012 List
– Data 2006-2010 plus legacy sites
• Lake Wylie, SC not impaired
• Fishing Creek Reservoir: P, N, pH, chl-a
• Great Falls Reservoir: P, N, chl-a
• Cedar Creek Reservoir: P, N, DO
• Lake Wateree: P, pH, DO
• 2014 List
– Data 2008-2012 plus legacy sites
– Draft for public comment February 2014
TMDL Development Resumed
• Model updates
– EPA 319 NPS Grant funds used to contract Systech
Water Resources, Inc.
– Extend WARMF model to 2012 (completed June 2013)
• Good response to our data requests
– Model calibration (scheduled completion April 2014)
Looking Ahead
• Web page – coming soon
• Information, reports, model files
• Stakeholder information meeting – Nov 19th
• Rock Hill Operations Center
• Email announcement soon
• Model calibration review – Jan-Feb 2014
• Draft calibration report and model files available
• Comments requested
• Final calibration report – Apr 2014
• Stakeholder review and coordination – 2014-2015
• Load Scenarios Allocations TMDL
Summing Up
• Significant Phosphorus reductions have been
implemented by NC and SC facilities
• WQ improvements in SC lakes have occurred
• Goal of the current modeling effort is to determine
what more is needed, considering all sources, to
achieve WQ standards
• Coordination with NCDWQ and EPA Region 4 has
begun and will expand to include stakeholders prior to
drafting the TMDL
• Questions?
•For more information
Wade Cantrell, Manager
303(d), TMDL, and NPS Section
SCDHEC Bureau of Water
[phone]
[e-mail]