Which Monitoring Program is Right for Your Lake?

Balancing Cost, Needs and Accuracy

 Stephen J. Souza, Ph.D.

And Fred S. Lubnow, Ph.D.Princeton Hydro, LLC

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Why Sample In the First Place?

Base lake management and restoration decisions on sound, objective, properly collected data

As with any ecosystem, temporal and spatial variability can be significant in a lake environment

A database must be suitably robust in order to account for this variability

If not, management and restoration decisions could could be faulty

Recipe for failure…wasted time and money

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The Key To Successful Lake Management …

Don’t Just Treat The Symptom…

Correct the Cause

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Without the Data You Can’t Make the Proper Diagnosis

Watershed Boundaries Soil PropertiesLand Use MorphometrySedimentationDO/ TemperaturePollutant ConcentrationsBiological InteractionsRecreational Needs

Nutrients

Hydrology

Trophic State

Collect Data Analyze Data

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In The Good Old Days

To account for spatial and temporal variability, the sampling program recommendations contained in the Section 314 Clean Lakes Program Guidance Manual required: Sampling over multiple seasons or over two years Sampling of multiple in-lake stations and tributaries Sampling of in-lake stations in profile or at multiple

depths, from surface to bottom Sampling of tributaries under wet and dry weather

conditions

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Good News – Bad News…

The resulting database enabled the development of a detailed restoration and management plan

The main problem: these monitoring programs were expensive to conduct

Lab and field labor costs alone were in the range of $40,000 to $50,000, with total costs often exceeding $100,000

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“Lite” Lake Sampling Plans

State-funded diagnostic studies often allowed a reduction in sampling intensity

This helped reduce cost, and did not significantly impact the accuracy of the database or decisions made

However, these “lite” monitoring programs still resulted in sampling and laboratory costs in the range of $20,000 to $30,000, with total costs often exceeding $60,000

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The Growing Season Approach As State and Federal funding became less

available, monitoring programs became funded primarily through local public and private funding sources

As a result, efforts were further scaled down Sampling was often limited to the “growing

season” or a few carefully selected dates Program lab costs typically in the range of

$10,000 to $20,000, with total costs around $35,000 to $45,000

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The Down Side

These “lite” monitoring programs resulted in substantial cost savings

But…with less data comes the potential for increased management decision errors

However, did every single management plan developed from a less than optimally detailed database fail?

The answer is…NO!

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Making Due With Less

Why? Because lake scientists made increasing use of: Predictive models In-situ monitoring equipment Information contained in reports and

published results contained in earlier studies available through such sources as NALMS, the U.S. EPA, state lake assessment programs, the USGS, and other agencies

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Good Data = Proper Management

As lake practitioners we arm ourselves with ample data before attempting to manage a lake

However, rarely is a monitoring program limited by neither budgetary nor time constraints

As a result, there is a limit on the amount of information that can be collected

If sampling is designed and conducted wisely though, correct management decisions can be made even with a less than optimal amount of data

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“One Size Does Not Fit All”

A cost-effective monitoring program provides the correct types and amounts of data needed to properly diagnose problems and guide decisions

A $10,000 program may look very similar a $100,000 program, but the end results will be very different

In determining cost-effectiveness must decide “which program has the least potential risk for error”?

The answer is not always that simple

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How Much Data Do I Need? Evaluating Potential Monitoring Options

1.   No monitoring

2.   Single event sampling

3. Multiple event, growing season

4.  Multiple event, single year, year- round monitoring program

5.  Multiple event, multiple-year sampling program

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The Lake Sampling Plan – The Starting PointThe Lake Sampling Plan – The Starting Point

Define your objectives and goal Identify the parameters of most value Establish an operating budget Develop a sampling plan (what, where, when) Identify fixed, easily located sampling stations Properly train / equip sampling team(s) Establish a quality control plan Setup a data management system Review data on a regular basis

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The “No Monitoring” Option

Rely on interviews with lake users, a visual assessment of the lake and its watershed, and an evaluation of any previous management efforts or existing data

Recommendations can deal only with obvious problems

While this approach may not always provide definitive solutions to existing problems, it is often useful as a start to the planning process

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Maintenance vs. Management

The “No Monitoring” option results in management decisions that focus on the symptoms of eutrophication and impacted water quality (e.g., algae blooms, infestation by nuisance aquatic macrophytes)

Difficult to identify true causes of a lake’s problems

The resulting recommendations may help alleviate or reduce the severity of these problems, but likely won’t correct the problem

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Site Visit Only What to expect: general info on costs and

management options, suggested next steps

What you miss: specific information on your lake or pond

Other considerations: success is almost entirely dependent upon the experience of the person conducting the site visit

Estimated costs: $1,000-$2,000

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If I’m Going to Sample…When Should I Sample

Sample frequently enough to meet your testing and monitoring objectives

Sample frequently enough to catch seasonal changes

Comprehensive lake/watershed studies must include storm sampling

Don’t forget about data that address user needs and recreation (e.g. bacteria, weed growth, fish)

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Single Sampling Event Program

Use one detailed sampling event to assess what is ailing lake

Timing is critical. Try to sample under WORST water quality conditions

Should depth profile measure dissolved oxygen, temperature, conductivity, and pH

Analyze nutrients, suspended solids, chlorophyll a, and measure Secchi disk transparency

If budget permits, include bacteria, phytoplankton, zooplankton, and macrophyte sampling

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Single Sampling Event Program

Examine physical, chemical, and biological properties of the lake

As with “No Monitoring” option, include Watershed assessment Review of any existing or historical data Critical assessment of ongoing management

efforts

Single event program generates a “snapshot” of the lake conditions

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Single Sampling Event Program

What to expect: water quality snapshot, general info on management options and costs, suggested next steps

What you miss: information on variability, watershed interactions, stream loading, ecological dynamics

Other considerations: sampling should be conducted under worse case conditions

Estimated costs: $5,000-$15,000

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Growing Season Approach Better approach than “Single Event” involves the

collection of data over multiple sampling events thru growing season (typically May - September)

Very cost-effective option for lake associations with limited budgets

Increases the number of sampling events and provides information on seasonal changes in lake water quality and lake dynamics

Addresses some of the data variability concerns associated with “snap shot” approach

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Focus on the “Problem” Period

Focus is placed on the collection of data when the worst water quality and lake conditions expected

Can observe trends, study ecological interactions and identify the causes of lake problems

This type of sampling yields insight concerning the applicability of certain restoration measures

Although relatively robust, may still fail to identify or measure important lake characteristics or trends

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Multiple Event, Growing Season

What to expect: good water quality data, management options, some info on variability, insight of problems/causes

What you miss: information long-term water quality, ecological dynamics, and fall and winter data, stream/storm data.

Other considerations: sampling should include month(s) when problems occur

Estimated cost: $15,000-$25,000

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Multiple Event, Single Year, Year-Round Program

The one-year sampling program most basic sampling approach contained in the Clean Lakes Program Guidance Manual (U.S. EPA, 1980)

Allows for more inclusive assessment, examine or identify problems that arise during non-growing seasons, most often includes stream/storm data

More robust, well suited for validation of data and predications derived from deterministic models

Additional data may not increase overall decisions relative to that developed through the “Growing Season” monitoring plan….However…

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Better Insight Gained Through More Frequent Sampling

Measure pollutant loading caused by spring runoff or summer thunderstorms

Monitor dissolved oxygen changes and winter-kill of fish when lake is ice covered

Measure organic and nutrient load from leaf-fall Track changes in the density, growth patterns,

speciation, and composition of macrophyte community

Measure internal phosphorus loading during fall destratification

Correlate storm loading impacts on water quality

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Multiple Event, Single Year, Year-Round Program

What to expect: good info on water quality, (including seasonal variation), management options, and costs; suggested next steps

What you miss: Inter-annual variations caused by changes in runoff,rainfall, weather

Other considerations: need to make sure all variables of interest are included, including biological sampling

Estimated cost: $25,000-$100,000

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Multiple Event, Multiple Year, Year-Round Programs

These programs decrease erroneous conclusions based on abnormal (excessive rain, drought, excessively hot summer or cold winter, etc.)

Multiple-year programs are also very well suited for tracking water quality improvements and quantifying success of management and restoration activities

Although provide additional information, these programs are obviously more expensive

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Multiple Event, Multiple Year, Year-Round Program

What to expect: good info on water quality, trends and variability, greater confidence in management options and costs

What you miss: the uncertainty associated with less intensive sampling

Other considerations: variables can be added as needed

Estimated cost: >$75,000

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But Sampling Frequency Is Only Part of the Story

Its not only how often to sample, but how many sampling stations

For a small pond or lake, a single sampling station may likely suffice

Bigger lake = more sampling stations Need to address unique water quality or use

conditions of coves, densely populated stretches of lakefront, deep versus shallow portions of the lake, tributary inlets, etc.

But…more sampling sites lead to increased costs

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So…What Should I Do? Ask, “What are we trying to accomplish”? A quick “look-see” of lake, can be

accomplished with a well-designed, suitably detailed one-day sampling program may suffice

However, if goal is to fully understand what is causing the eutrophication of your lake, and how best to channel your restoration and management efforts and funds in the improvement of conditions, a more intense sampling program will be required

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Think, Question and Prepare

Typically a seasonal or one-year type program needed to properly investigate lake dynamics or develop data needed to support a given restoration approach or technique

The worst that you can do though is to proceed in the management of your lake without any data collection. Even the simplest program, if properly designed and thought out, can provide good information useful in guidance of management and restoration decisions

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Thank You

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Questions or More Information

Stephen J. Souza, Ph.D.Stephen J. Souza, Ph.D.Princeton Hydro, LLCPrinceton Hydro, LLC

Suite1, 1108 Old York RdSuite1, 1108 Old York Rd

P.O. Box 720P.O. Box 720

Ringoes, NJ 08551Ringoes, NJ 08551

Ssouza@princetonhydro.comSsouza@princetonhydro.com