Nutrient Export to Green Bay under Various Watershed Management and Climate Scenarios

Kevin Fermanich, UW – Green Bay Paul Baumgart, Alexis Heim, UW-Green Bay

David Lorenz, UW–Madison, J.Val Klump, UW–Milwaukee

9th Biennial State of Lake Michigan Conference Traverse City, Michigan October 28-30, 2015

Cultivated Crops

Deciduous Forest

Developed, High Intensity

Developed, Low Intensity

Developed, Medium Intensity

Developed, Open Space

Emergent Herbaceuous Wetlands

Evergreen Forest

Hay/Pasture

Herbaceuous

Mixed Forest

Lower Fox

Upper Fox

Wolf R.

(NLCD 2011)

Green Bay landscapes and land-uses

*

*

L. Winn.

SOURCES OF P TO GREEN BAY

• >75% is from nonpoint sources (NPS)

Fox River

ü Nutrient Loads – strongly event driven and related to landscape conditions - agricultural activities are big factors

• Dairy has significant role in the Green Bay Watershed

June 2, 2014

May 12, 2014

Cty Rd D USGS/UWGB station; 59% of Plum Creek watershed area (54 km2). Photos from W. Plum ~ other 39% of area.

4,521 kg/d

Last 4 years: 11 days >1000 kg/d 2014: Total Load = ~2x GBMSD

Managing the Watershed Objectives:

• Expand Lower Fox TMDL for quantifying inputs of nutrients and suspended sediments to Green Bay to include entire Fox-Wolf Basin (apply SWAT model)

• TMDL P reduction goal for outlet of Fox River ~43%

• Assess efficacy of implementing alternative land management practices throughout the watershed

• Assess impact of future regional climate change projections (WICCI data)

• Provide inputs for downstream Green Bay models (MAT)

Soil and Water Assessment Tool - SWAT • USDA – ARS model: J.G. Arnold, J.R. Williams, Temple Texas • Continuous daily time step, river basin/watershed scale

model ------- physically based • Routes water, sediment, and nutrients to watershed and

basin outlets • Predict impacts of management on water, sediment and

chemical yields • Long-term simulations of many decades • Tracks crop growth, tillage, fertilizer/manure application,

nutrient cycling on a daily basis • Daily inputs of climate data

• Calibrated and Validated against robust, multi-scale

watershed monitoring datasets.

Year 2011 NASS Cropland Land cover (modeled as combination of 2006-2011 NASS CDL’s & other images)

Soil Hydrologic Group Brown = higher runoff , less base flow Yellow= low runoff, high base flow

Stream Monitoring Stations for calibration & validation 4 SWAT models ~371 sub-watersheds

SWAT Simulated Total Phosphorus Yields

(kg/ha) from Fox-Wolf Basin

Routed to Lower

Green Bay

Approximate Impact of Applying BMP’s to sub-watersheds over the

Phosphorus Yield Threshold (“area affected” is total sub-watershed area, so actual

area Ag affected is less)

Phosphorus

TARGET Threshold

(kg/ha) Total P

(kg)

% of Fox-Wolf Basin Non-Pt. Load to Bay

(base= 566,200 kg)

Total Area

Affected (sq. Km)

Total Area

Affected ( % )

2.00 49,864 8.8% 221 1.4%

Total “effective”

BMP Efficiency

Total P (kg)

Reduced

% Load Reduction to

BAY 70% 34,905 6.2%

Select Sub-watersheds by their yield of P

P target threshold (kg/ha)

1.50 1.00 0.75

% F-W NPS load 27 44 53

Area (%) 5.1 9.8 13.4

% load reduction to Bay (70% effec.)

19 (106,795 kg) 31 (172,465 kg) 37 (207,973 kg)

Implement 70% effective NPS BMPs in watersheds with >0.5 kg/ha TP loss (18% of area) à ~240,000 kg

reduction of TP

Phosphorus

TARGET Threshold

(kg/ha) Total P

(kg)

% of Fox-Wolf Basin Non-Pt. Load to Bay

(base= 566,200 kg)

Total Area

Affected (sq. Km)

Total Area Affected

( % ) 0.50 340,845 60.2% 2,911 18.0%

Total “effective”

BMP Efficiency

Total P (kg)

Reduced

% Load Reduction to

BAY 70% 238,591 42.1%

P Reduction: Alternative Management Scenarios (Outlet of Fox R., WY2009-13 climate)

Alternative Management Scenarios Reduced Tillage & Soil-P; Pt Source reduced

Alternative Management Scenarios More feasible Tillage, & Soil-P & Cover Crops

What about targeting these high P areas with a combination of alternative management?

Phosphorus

TARGET Threshold

(kg/ha) Total P

(kg)

% of Fox-Wolf Basin Non-Pt. Load to Bay

(base= 566,200 kg)

Total Area

Affected (sq. Km)

Total Area Affected

( % ) 0.50 340,845 60.2% 2,911 18.0%

Total “effective”

BMP Efficiency

Total P (kg)

Reduced

% Load Reduction to

BAY 70% 238,591 42.1%

Alternative Management Scenarios Targeted High P sub-watersheds, +grazing

Targeted high P export sub-watersheds

Comprehensive BMP Implementation Plum Creek Sub-watershed Scenarios

Alexis Heim -UWGB

Baseline Conditions (15 yr annual avg.)

75% Ag

Comprehensive BMP Implementation Plum Creek Sub-watershed Scenarios

Alexis Heim -UWGB

58-61% ~70%

P

Climate Change Scenarios: Downscaled, projected climate 2046-65. A1B emission scenario. • ECHO 2012 (2nd warmest GCM, as

projected) • MRI 2012 (2nd coolest GCM, as

projected) Meteorological Research Institute Coupled Atmosphere–Ocean General Circulation Model, version 2.3.2 (D. Lorenz, Ctr Climate Research/WICCI, U. Wis.) • CO2 changed to 550 ppm % Precip change from baseline

Seasons MRI Warmer/Wetter

climate model Winter 28% Spring 10% Summer 5% Autumn 10%

Seasons Change Max °C

Change Min °C

Winter (Dec-Feb) +3.9 +4.8 Spring (Mar-May) +2.2 +2.5 Summer (Jun-Aug) +1.9 +2.5 Autumn (Sep-Nov) +2.3 +2.2 (Comparison to Appleton, WI station)

100%

105%

110%

115%

120%

125%

130%

ECHO (avg 2011-13) MRI (avg 2011-13)

Rela

tive

Chan

ge P

redi

cted

by

SWAT

(%)

SWAT-Simulated Climate Change Scenarios: Fox River Outlet

Flow TSS TP

UWGB Sept 2015

Under current management, how will loads at the Fox R. outlet change under projected climate?

v. warm, moist

~10+% increase P

warmer, wetter

How will alternative management perform under projected climate? Plum Creek Sub-watershed Scenarios

Alexis Heim -UWGB

Green Bay MAT: User-Define Statistics (Aggregation/Time Period)

Summary • >80% of P is from landscape sources à ag • ~50% of NPS load to bay is from LFR and L. Winn sub-basins • Reducing soil-P and tillage, plus cover crops à >40%

reduction IF basin wide implementation • Targeting high P watersheds (~18% of basin) à >23%

reduction • >10% increase in P export under future climate & base

management • Current set of improvement practices will lessen climate

impacts but not suffice to reach WQ goals • Promising actions in the watershed: LFR Demo Farms,

Silver Creek Pilot Project, GLRI, Grazing, farmer innovators

UW Milwaukee School of Freshwater Sciences: Val Klump, Hector Bravo, Shelby LaBuhn, Sajad Hamidi, Jim Waples, others UW Green Bay – Kevin Fermanich, Paul Baumgart, Alexis Heim, M. Zorn, D. Dolan* Green Bay Metropolitan Sewage District – Bill Hafs John Kennedy, Tracy Valenta, Erin Wilcox, UW Madison Center for Climate Research – David Lorenz UW Madison/UW Extension Environmental Resources Center – Chad Cook, Ken Genskow, LimnoTech – Joe DePinto, Ed Verhamme, Dan Rucinski WI DNR – Keith Marquardt, Laurel Last Wisconsin Sea Grant – Julia Noordyk, Vicky Harris Oneida Nation – Michael Finney NOAA Center for Sponsored Coastal Ocean Research USGS – Dale Robertson

Restoration of Green Bay: Managing the Watershed

• Restoring the health of the Green Bay ecosystem under a changing climate: Modeling land use, management, and future outcomes

• Green Bay Hypoxia: Watershed Inputs, Impacts, and Management Project Team:

J. Val Klump, UW-Milwaukee, Co-Director Kevin Fermanich, UW-Green Bay, Co-Director Paul Baumgart, Mike Zorn, UW-Green Bay Hector Bravo, James Waples, Sajad Hamidi, Shelby LaBuhn, UW-Milwaukee Joe Depinto, Ed Verhamme, LimnoTech LLC David Lorenz, Center for Climatic Research, UW-Madison Bill Hafs, Erin Wilcox, NEW Water Keith Marquardt, WDNR Chad Cook, Ken Genskow, UW-Extension Michael Finney, Oneida Nation Julia Nordyk, WI Sea Grant

NOAA Center for Sponsored Coastal Ocean Research Coastal Hypoxia Research Program NOAA-NOS-NCCOS

Support:

Refine linked models and Green Bay MAT → better informed management

NOAA Center for Sponsored Coastal Ocean Research Coastal Hypoxia Research Program NOAA-NOS-NCCOS

PLUM Creek at USGS StationFlow (mm) Sed (ton) P (kg)

WY2011 333 6,979 13,811WY2012 133 3,509 6,122WY2013 282 6,504 12,868WY2014 262 11,651 18,691average 253 7,161 12,873yields 333 1.32 2.37

May 12, 2014