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 pH

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

pH The Key To Successful Lake Management … Dont Just Treat The Symptom… Correct the Cause

pH Without the Data You Cant Make the Proper Diagnosis Watershed Boundaries Soil Properties Land Use Morphometry Sedimentation DO/ Temperature Pollutant Concentrations Biological Interactions Recreational Needs Nutrients Hydrology Trophic State Collect Data Analyze Data

pH 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

pH 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

pH 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

pH 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

pH 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!

pH 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

pH 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

pH 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

pH 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

pH The 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

pH 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

pH 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 lakes problems The resulting recommendations may help alleviate or reduce the severity of these problems, but likely wont correct the problem

pH 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

pH If Im 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 Dont forget about data that address user needs and recreation (e.g. bacteria, weed growth, fish)

pH 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

pH 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

pH 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

pH 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

pH 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

pH 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

pH 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…

pH 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

pH 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

pH 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

pH 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

pH 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

pH 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

pH 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

pH Thank You

pH Questions or More Information Stephen J. Souza, Ph.D. Princeton Hydro, LLC Suite1, 1108 Old York Rd P.O. Box 720 Ringoes, NJ