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Discover tips for maximizing lagoon performance through optimization and maintenance practices. Learn about vegetation control, chemical vs. mechanical variables, and monitoring water quality indicators. Stay informed on effective problem-solving strategies in wastewater lagoon systems.
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Maximization of Lagoon performance through optimization and maintenance by: Josh jabalera And Kristina hartley
Lift Station: • Check daily • Remove all garbage and debris • Check Floats and probes • Note and investigate abnormal inflows • Discussion – If its in the lift station its in the lagoon
Headworks • Approximately 40% BOD removal • Decreases rate of sludge accumulation • Prolongs life of pumps • Discussion
Community Outreach: To Flush or not to Flush – You Can Help! • Cigarette butts • Chewing gum • Kitty litter • Sanitary napkins, tampons • Bandages • Diapers • Pills/Prescription medications • Poisons or any other hazardous waste • DO NOT FLUSH • Baby wipes, disinfectant wipes, etc.. (even if they are “flushable”) • Facial tissues, Q-tips, cotton balls • Napkins, paper towels • Dental Floss • Egg shells, nutshells, coffee grounds • Fats, oils, greases • Hair • Condoms
Toxic Substances Can Have Adverse Effects • Can be harmful to microbiology within the lagoon • Can kill aquatic life • Harmful to downstream users • Discussion
Poor Vegetation Control Can Cause: • Oxygen Depletion • Excess Sludge Accumulation • Insect Problems • Damage to Dikes and Liners • Burrowing Animal Problems • Odors • Oxygen Depletion • Short-Circuiting • Poor Circulation
Chemical Vs Mechanical Discussion
Variables Affecting Pond Performance • Chemical Influences • Natural Influences • Physical Influences
Chemical Influences • Loading • Alkalinity • pH • Salinity • Toxicity • Composition of Liner and Dikes
Natural Influences • Solar Radiation • Temperature • Wind Speed • Precipitation • Evaporation • Ice Cover • Bacteria & Algae
Physical Influences • Pond Configuration • Pond Hydraulics • Retention Time • Seepage • Inflow & Infiltration • Pond Dimensions • Aeration & Mixing
“Eleven Things You Must Know to Effectively Solve Problems in Wastewater Lagoon Systems” -Steve Harris
Is your lagoon properly sized for the community, industry, or load it serves? • (Flow in MGD) x (Average BOD in mg/l) x (8.34 lbs/gallon) • Acres in Cell #1 • Typical facultative ponds can be loaded to 32 lbs BOD/acre/day • Primary cell should be removing between 60% to 80% of the influent BOD
2. What are the pond dimensions and depths? • Important to help determine: • Detention time • Loading rate • Estimated time to desludge
3. What is the theoretical retention time? What is the actual retention time? What is the flow? • Must know average daily flow and the volume of each pond • AVOID SHORT CIRCUITING!!!!
4. How much sludge has accumulated at the bottom of the pond? • Algae blooms becoming worse • Sludge accumulates at about 1 inch/yr • At 18 inches pond performance deteriorates
5. What are the dissolved oxygen (D.O.) levels measured at different times and water column depths and different places throughout each lagoon. For an aerated lagoon, how many pounds of Oxygen are being supplied per pound of BOD5 added?
6. What is the pH at different depths and locations within the lagoon? What is the different times of the day, and between each lagoon? • Changes with depth • Where to sample • Affects pond’s ability to kill pathogens
7. What are the BOD5 and CBOD5 of EACH pond? • Primary Cell should be removing 60 to 80% of your influent BOD • Run series of BOD5 diagnostics
8. Have any new industries moved to the community? Have there been any changes to cleaning procedures or new disinfectant added or changes in cleaning chemicals? • Should be added to the lagoon system slowly over time
9. Know how the lagoons temperature changes throughout the year and through the water column • Temperature trends will help predict blue green algae bloom, spring or fall turnover, and odors
10. Know what types of solids are leaving the lagoon effluent • Each solid has meaning • Sludge particles may mean time to desludge • A daphnia bloom may be picked up as TSS • Consult with lab to identify solids
11. Know the position and location of the influent, effluent, and transfer structures • Can adversely affect optimal water flow • Can cause short circuiting • Effluent structures can pass bottom solids into successive cells
Temperature Directly Affects the Rate of Biological Activity • Every 10 degree reduction in temperature will reduce microbial activity by 50%
Water Temperature Directly Affects: • Chemical and Biological reactions • The reaction rate constant used in pond design • Bacterial mortality rate • Thermal stratification • Destratification • Density driven circulation • Oxygen solubility in water • Algae, protozoa, and bacteria populations
Operations During Winter • Remove some aeration or reduce horsepower • Do not operate re-circulation • Maximize pond depth, liquid level • Maximize retention time • All cells should be operated to maximize retention time
How Temperature Affects Pond Mixing Cooler Fall Temperatures
Fecal Coliform Problems in the Winter • Low winter time ultraviolet radiation and pH mean lower potential pathogen die-off rates • As warmer influent water enters an ice covered lagoon, raw wastewater can ride high in the water column over colder denser water creating a short-circuit
Testing Procedures for Optimizing Lagoon Performance • Define Your System • Sample Collection, Analysis, and Management • Results Interpretation • Modifying Your System to Achieve Performance
Defining your System • Influent and Effluent • Head Works • Operated in Series or Parallel • Diagram • Consider Short Circuiting
2. Sample Collection and Analysis • Time of Day • Depth of Sample • Areas of Disturbance • Grab Sample • Composite Sample
Intra-Pond Sample Analysis • pH • Dissolved Oxygen (DO) • Ammonia • Nitrate • Alkalinity • Temperature • (COD), (sCOD), (BOD5), (SBOD5) • Total Suspended Solids (TSS) • Sludge Blanket Profile
3. Results Interpretation • Should settle large organic particles • Trend the data over a period of time • Look at the results between each cell • Pinpoint areas of failing treatment
4. Modify Your System to Achieve Performance 5. Repeat Steps One through Four
Conditions that Reduce Performance • Flow through the system • Sludge accumulation • Available oxygen • Toxicity • Organic Load
Influences on Pond Hydraulics • Pond inlet position, size, and location • I & I and varied flow rates • Pond outlet position • Water temperature • Sludge accumulation • Position of aeration equipment and baffles • Wind
References: Wastewater Lagoon Troubleshooting By: H&S Environmental, L.L.C.
Thank You!!