Nutrient Criteria and Strategies Adventures in Science-based Policy II

Chris Zell, PHWQ

Geosyntec Consultants

REGFORM Water Seminar

September 5-6, 2013

Columbia, Missouri

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

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

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

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

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.

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

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 ?

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.

Percentiles are Problematic...

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

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

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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

Reducing and Managing Nutrients

NNC Challenges

An Ecological Stressor-Response Example

Ohio’s newly minted Trophic Index Criterion (TIC)

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

Reducing and Managing Nutrients

NNC Challenges

Achievability and Costs

Stormwater

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

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

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

Credit Supply and Demand Curve

Total nutrient abatement cost decreased by $1.4 million annually

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!

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

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