This document outlines a presentation on nutrient criteria and management strategies. It discusses national drivers for managing nutrients like the Clean Water Act and hypoxia issues. It describes two options for reducing and managing nutrients: nutrient reduction strategies and numeric nutrient criteria. Nutrient reduction strategies involve watershed prioritization, load reduction goals, and best management practices. Developing numeric nutrient criteria is challenging due to issues with statistical approaches, modeling and costs. The document also discusses an example nutrient trading project and key findings, noting trading can lower costs but criteria need flexibility.

1. Nutrient Criteria and Strategies
Adventures in Science-based Policy II
Chris Zell, PHWQ
Geosyntec Consultants
REGFORM Water Seminar
September 5-6, 2013
Columbia, Missouri

2. Nutrient Session Outline
 Chris -
Nutrient Criteria and Management Issues
• National Drivers
• Reduction Strategies
• Numeric Criteria (N, P, and algae)
• Point and Non-point Source
Treatment
• Nutrient Trading
 Karen -
Regional and National Nutrient Policy Issues

3. National Drivers
 Clean Water Action Plan
 Chesapeake Bay TMDL
 Mississippi River Basin & Gulf
Hypoxia
 Legal Challenges/Petitions
 Nutrient Criteria
 Low #’s, High Costs
 Nutrient Reduction Strategies,
TMDLs and Permits

4. Reducing and Managing Nutrients
‘Option’ A - Nutrient Reduction Strategies
 March 16, 2011 EPA Memo from Nancy Stoner
 Includes an 8 element nutrient reduction strategy
 Comparable efforts underway or completed in some
states (e.g., KS, MS, LA)
1. Prioritize watersheds
2. Set watershed load reduction goals
3. Ensure effective point source permits
(including CAFO, MS4)
4. Target most-effective Ag BMPs
5. ID tools for small on-site systems and runoff
6. Accountability and verification measures
7. Public reporting
8. Develop nutrient criteria work plan & schedule
Planning
Accounting

5. Reducing and Managing Nutrients
Example Nutrient Reduction Strategies
 Kansas – adopted nutrient reduction plan in 2005
 Watershed Restoration Action Plans (WRAPs)
 More than 40 nutrient TMDLs established
 Point source nutrient reductions (POWTs > 1 MGD)
(1.5 mg/L ~ TP, 8 mg/L ~ TN with BNR, as annual averages)
 Quantified nutrient reductions in agriculture runoff
 Reduction reporting critical to NNC schedule & lawsuits
 Setting Expectations – restoration pending: (1) funding
mechanisms and (2) socio-ecological response times

6.  Wisconsin
- developed in response to Gulf Hypoxia
Action Plan (2008)
~ 45% reduction in nutrients to Gulf (1995 as baseline)
- PRESTO tool available to estimate US NPS loads
Reducing and Managing Nutrients
Example Nutrient Reduction Strategies
15-year schedule
Interim TP limit of
0.6 mg/L may
apply.

7. Reducing and Managing Nutrients
Example Nutrient Reduction Strategies
 Missouri – In Progress
 Approximately bi-monthly meetings coordinated by
Steve Walker
 Table of Contents (outline): August – December 2012
 More than 90 stakeholders representing over 30 organizations
 Document preparation - MU and Lincoln University
 Nutrient Reduction Strategies – Poll (8/20/2013)
51 questions, 19 participants
2 11.11%
2 11.11%
0 0%
2 11.11%
11 61.11%
1 5.56%
Totals 18 100%
1.) Strategy 1 Implement nutrient management plans
on all cropland acres which include the 4Rs (right source,
right rate, right time, and right place). (multiple choice) Responses
Strongly Oppose
Moderate Opposition
Neutral
Moderate Support
Strongly Support
No Opinion

8. Reducing and Managing Nutrients
‘Option’ B – Numeric Nutrient Criteria
 Element 8 of nutrient reduction strategy is Numeric
Nutrient Criteria (NNC)
 Intended to reduce occurrence of:
Condition Use
Objectionable Color
or Bottom Deposits
Narrative
Low Transparency Recreation and/or Aesthetics
Algal Bloom
(O2 depletion)
Aquatic Life
Algal Bloom
(Community Composition)
Aquatic Life
Change in
structure or
function ?

9. How are NNC Developed?
Approach Description
Percentile or Reference
Approach
Statistical Frequency Analysis
(75th Percentile of Reference Streams to 25th
Percentile of All Data)
Water Quality Modeling
Model algal biomass in response to nutrient
loads (QUAL2K, WASP, regressions etc.)
Ecological Stressor-Response
Statistical or process-based modeling of
changes in bioindicator(s) to nutrient loads.
Composite
(aka, Weight-of-Evidence)
Multiple approaches to arrive at a range or
matrix of nutrient endpoints. Criteria may be
described as range or single value based on
strength of corroboration.

10. Percentiles are Problematic...

11. Reducing and Managing Nutrients
NNC Challenges
 Percentile Approach
Subecoregional values applied as wasteload allocations in several recent Missouri
TMDLs. Default values listed as federal WQ standards are percentiles.
Ecoregional Nutrient
*Benchmark - Rivers
Ecoregion 9
(Northern Mo)
Ecoregion 10
(Missouri Bootheel)
Ecoregion 11
(Ozarks)
Ecoregion 6
(NW Missouri)
Total Phosphorus
(µg/L)
37 128 10 76
Total Nitrogen
(µg/L)
700 760 310 2180
Sestonic Chl-a (µg/L) 1 2 2 3
Periphyton Chl-a
(mg/m2)
20 N/A N/A N/A
*Aggregated Ecoregional 25th Percentiles

12. Water Quality Modeling
 Algal Biomass Endpoints
The reality of co-limitation
Periphyton = Photo – Respiration – Death – Grazing – Scour
Co-limited by: light and nutrient supply (and substrate)
Some systems may be more sensitive to changes in light,
grazing or scour than nutrients – on an annual basis
79
27
64
77
38
2930
3
19
6
19
3
0
10
20
30
40
50
60
70
80
90
Site 1 Site 2 Site 3 Site 4 Site 5 Site 6
GEOMETRICMEAN,
INMILLIGRAMSCHLOROPHYLL-APER
SQUAREMETER
Less-Shaded
Shaded

13. Reducing and Managing Nutrients
NNC Challenges
 Stressor - Response
 Uncertainty and Error Propagation
That is, the dose-response relationship is variable
and may be waterbody specific ($$$ science)
Source: WEFTEC 2010, Watershed Workshop. US EPA

14. Reducing and Managing Nutrients
NNC Challenges
 An Ecological Stressor-Response Example
Ohio’s newly minted Trophic Index Criterion (TIC)

15. Reducing and Managing Nutrients
NNC Challenges
 An Ecological Stressor-Response Example
Ohio’s newly minted Trophic Index Criterion (TIC)
Default limits if Trophic Index is not acceptable:
TP = 1.0 mg/L and DIN = 10 mg/L
If not acceptable after two permit cycles then:
TP < 0.3 mg/L (use and habitat dependent)
DIN = 3 mg/L

16. Reducing and Managing Nutrients
NNC Challenges
 Achievability and Costs
Stormwater

17. Reducing and Managing Nutrients
NNC Challenges
 Achievability and Costs
Domestic Wastewater
Nutrient Raw Wastewater
Secondary Effluent
(no removal)
Advanced
Treatment
(BNR)
Enhanced
Nutrient
Removal (ENR)
Limits of
Technology
(LOT)
Total Phosphorus
(mg/L)
4 - 8 4 - 6 1 0.25 - 0.50 0.05 - 0.07
Total Nitrogen
(mg/L)
25 -35 20 – 30 10 4 - 6 3 - 4
From WERF Limits of Technology and Research on Nutrient Removal Webinar, October 8, 2008

18. Missouri Innovative
Nutrient Trading Project
 USDA NRCS, St. Louis
MSD, MCGA, ERC, MPUA,
MDNR
 Assist in Developing
Trading Procedures
 Improve Water Quality
 Provide Regulatory
Flexibility
 Lower Compliance and
Abatement Costs
 Simulated Trading Exercise

19. What is Water Quality Trading?
 Market-Based Compliance
System Whereby One
Discharger Buys or Sells
Pollution Credits from Another
 Point-to-Point
 Point-to-Nonpoint
 Tool to help meet water quality
goals
 at a lower cost
 sooner than might otherwise occur
 fit within other infrastructure needs
 multiple benefits
 Requires flexible implementation of
stream criteria

20. Credit Supply and Demand Curve
Total nutrient abatement cost decreased by $1.4 million annually

21. Nutrient Trading – Key Findings
1. Trading areas should be maximized
2. Feasibility is sensitive to trading ratio
3. Point-to-point trading can be the most cost-effective WQT
- this includes Big Rivers
4. WWTPs should be able to set the cap for trades
- technology-based limits may limit cost-effectiveness for a WQT program
($/lb abated)
5. An exchange or clearinghouse may be needed to minimize transaction costs.
6. Liability, monitoring, and enforcement could prohibit WQT
7. Raising agricultural baseline would reduce cost-effectiveness and the number
of WQT partners
 End of pipe vs. watershed-based NNC is key!

22. Take Home Summary
A successful nutrient reduction strategy is a flexible
approach for reducing nutrient exports....and may serve
as a buffer against early adoption of NNCs.
NNCs:
- are developed according to 3 basic approaches
- are generally: (1) currently not attainable and/or (2) currently
not affordable by most sectors
- An approach that recognizes uncertainty and embraces
biological confirmation appears promising (FL, OK, others)
 A successful WQT program can improve abatement
efficiency...if NNC or NRD are flexibly implemented

23. Thank You!
For further information:
Chris Zell, PHWQ
Geosyntec Consultants
1123 Wilkes Blvd., Suite 400
Columbia, Missouri 65201
Phone: 573.443.4100
Email: czell@geosyntec.com