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BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005
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BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Jan 16, 2016

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Page 1: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

BMPs forAquaculture Production

Lori Marsh, Associate Professor, Biological Systems Engineering,

Virginia TechSeptember 19, 2005

Page 2: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Aquatic Animal Production(CAAP/AAP) Systems:

• Flow-through

• Recirculating

• Net pen and cages

• Ponds

• Lobster pounds, Crawfish, Shellfish, Aquariums, and Alligators

Page 3: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Flow-through Systems

• Constantly flowing culture water

• Commonly use raceways or tanks

• Found throughout US

• Require consistent volume of water

• Most use well, spring or stream water as source

• Primary method to grow salmonid species such as rainbow trout.

Page 4: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Recirculating Systems

• Highly intensive culture

• Actively filter and reuse water

• Water treatment including– Ammonia removal– Solids removal– Oxygenation– Temperature control….

• Capital intensive at startup

Page 5: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.
Page 6: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.
Page 7: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.
Page 8: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Net Pens and Cages

• Suspended or floating holding systems

• Located along a shoreline or pier or anchored off shore

• Rely on natural water movement to assure water exchange/quality for fish

Page 9: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

What’s the Problem with CAAPs?

• 4,200 commercial facilities (1998 USDA census)

• Water quality concerns include– Suspended solids, P, NH3, BOD

– Drugs (e.g. oxytetracycline or formalin)– Chemicals (e.g. copper-containing pesticides)– Pathogens (primarily a concern for native

biota)

Page 10: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

BMPs for Feed Management

• Applicable to all systems• Avoid overfeeding• Match feeding to feed requirements • Direct feed to fish• Use quality feed, and store to reserve nutrient

quality• Handle feed to minimize fines• Active feed monitoring (net pens): detects when

feed pellets are passing below fish.

Page 11: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

BMP for Removal of Solids in a Flow-through System

• Quiescent Zones typically constructed with wire mesh to exclude fish from last 10% of raceway.

• Designed to insure that overflow rate is smaller than particle settling velocity.

• Solids typically removed by suction through a vacuum head.

Page 12: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Other BMPs for Solids Removal• Sedimentation basins

– Off-line settling (OLS) basins receive water and solids slurry from Quiescent Zone (QZ).

• Note: QZ + OLS are most common settling system for flow-through systems.

– Full-flow settling (FFS) systems stand alone and collect water flow from entire facility (need 2 operating in parallel for solids removal).

• Secondary Settling – Microscreens– Vegetated ditches– Constructed wetlands

Page 13: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Solids Disposal

• Dewatering – Natural evaporation– Mechanical assistance

• Filtration• Squeezing• Capillary action• Vacuum withdrawal• Centrifugal

– Chemicals are often added to assist with the dewatering process

Page 14: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Solids Composting

• Dewatered sludge mixed with bulking agent to add carbon, reduce moisture, increase aeration

• Must be aerated (turned or by adding air)

• Often screened to remove bulking agent– Advantages: reduces volume, stabilizes

material, heating destroys pathogens, value added product

Page 15: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Vermicomposting of solids

Vermicomposting uses earthworms to transform organic wastes and results in two

saleable products: vermicompost and worms.

VERMICOMPOST WORMS

Page 16: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

WHY CONSIDER VERMICOMPOSTING?

Two saleable products

Possibility of worms as fish feed

Worm composting faster than microbial

Worms turn the material so machines/people don’t have to

Vermicomposting suitable for high-moisture waste

Page 17: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

After settling, the contents were run

through a hydroclone.

HYDROCLONE

Page 18: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

The bins in operation

WORM BINS

Page 19: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Material from beds was run through a

trommel screen resulting in

screened material, unscreened

compost, and worms.

WORM SEPARATOR

Page 20: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Processing rate very slow during extreme temperature conditions >29 C or < 10 C; therefore an unconditioned greenhouse does not appear suitable for this process.

During more optimum temperature conditions, worms processed 2.3 kg dry sludge/m2-week.

For the estimated sludge production at BRA, a 30.5 m x 91.5 m (100’x300’) structure would be required to house sufficient worm beds.

CONCLUSIONS

Page 21: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Land Application of Solids

• Can land apply without dewatering – Hydraulic limitations not nutrient

• Need provisions for times of frozen ground

• BMPs for land application of animal wastes would apply, e.g. site conditions, weather, crop nutrient uptake, application rates, land availability, setbacks, slopes, neighbors, etc.

Page 22: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Waste Treatment Options for Effluent

• POTW

• Lagoons: BMPs for lagoons apply, e.g. site selection, design, start up, maintenance, record keeping, clean water diversion, etc.

Page 23: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Mortality Management

• Avoid disease outbreaks

• Inspect daily, remove mortality promptly

• Proper disposal—composting, rendering

Page 24: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

BMPs for Ponds

• Avoid discharges e.g. seine harvest rather than draining; maintain freeboard for storm volume, drain from top when necessary.

• Implement erosion control for pond ( protection from waves, aerators, vehicles, etc.) and watershed.

• Manage rainwater: divert excess runoff,• Maintain good vegetation and avoid livestock production

in watershed.• Use drugs and chemicals only as needed, use only FDA-

and EPA-approved water quality enhancers and follow label directions carefully.

Page 25: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

Constituents of concern

• Nutrients• Bacteria (?)

– Carr, O.J. and R. Goulder. 1993. Directly counted bacteria in a trout farm and its effluent. Aquacult. Fish. Manage. Vol 24, no. 1, pp. 19-27.

• Pharmaceuticals (?)– Halling-Sorensen, B. et al. 1998. Occurrence, fate

and effects of pharmaceutical substances in the environment—A review. Chemosphere. Vol 36, no.2, pp. 357-393. Jan. (Nice abstract. Unfortunately, article is in German.)

Page 26: BMPs for Aquaculture Production Lori Marsh, Associate Professor, Biological Systems Engineering, Virginia Tech September 19, 2005.

References

• Claude E. Boyd. Guidelines for aquaculture effluent management at the farm-level. Aquaculture. Vol 226 Issues 1-4, Oct. 2003. pp 101-112.

• USEPA. BMPs for CAAP Facilities. www.epa.gov/guide/aquaculture.