MilkingCenterWastewa terOptions

Milking Center Wastewater Options & MN Research: 

Milking Center Wastewater Options & MN Research

S.E. MN Milk House Wastewater Treatment Project: 2004-2007: 

S.E. MN Milk House Wastewater Treatment Project: 2004-2007 Winona & Goodhue Counties Four systems in each county 50 to 155 cows, two with parlors All with septic tanks and either--- * Media filter– expensive (Total= 12-13K) * Aerobic treatment to leach field—expen * Irrigation * Bark bed/strips

Iowa DNR Rules: 

Iowa DNR Rules Prohibits discharge to waters of the State polluting waters of the State discharge to road ditches MN rules says < 25 mg/L BOD5 to release to surface water MN rules say if released to leach field need < 200 mg/L BOD5

What is Milk House Waste?: 

What is Milk House Waste? Results from cleaning and sanitizing the milkers, pipeline and bulk tank Bacteria Nutrients—Nitrogen and Phosphorus Residual milk– must be limited Cleaners/chemicals Water

Concerns with Milk House Waste: 

Concerns with Milk House Waste High ammonia load – can cause fish kills High organic load – lowers water quality by reducing oxygen levels High phosphorus load –promotes algae growth

Septic Tank Function/Size: 

Septic Tank Function/Size Reduction of BOD and Total Susp Solids Time in septic tank allows soaps, bedding mtl, milk fats to float to top to form a scum layer and heavier solids including floor lime, dirt, and biomass to settle to the bottom to accumulate a sludge layer Pumped when sludge or scum is too thick (1-2x/year) Min. septic tank volume = 4X Daily Load

Overall summary of options:: 

Overall summary of options: Drain or pump into manure storage Drain or pump into separate storage (DNR prefers storage not be below ground) Bark Bed/Strips Treatment System Irrigation System–two types of sprinklers Irrigation System-@ 6 months-tow 1.5” line

Wastewater Volume/Parameters: 

Wastewater Volume/Parameters Range is 2 to 4 gal/head/day– (no parlor) BOD leaving holding tank = 600 to 1500 mg/L BOD5 leaving sep. tank filter = 800 mg/L Total suspended solids= 60 to 1150 mg/L Total Nitrogen = 180 – 240 mg/L (1-2 pounds/1000 gallons) Phosphorus = 12 -38 mg/L

Bark bed/strips treatment: 

Bark bed/strips treatment Relatively flat area (<5% slope), filled with 2-3 ft of bark The bark provides a carbon source for the aerobic microorganisms Good wastewater distribution needed Organic material needs to be added @ fall Use 8 sq ft bed/gallon of daily wastewater or 30 sq ft per cow.

Bark bed/strips continued: 

Bark bed/strips continued Can use distribution bed in 12” high diked well drained soil area. Cover drain field rock with full length pipes and geotextile f. Place 24” wide chamber on scarified surface (cut grass first). Put 2” pipe with ¼” holes 3 ft o.c. in top of chamber system Use 12” bark on chamber system – winter

Examples of 2 Bark Systems: 

Examples of 2 Bark Systems Bark options for 60 cow stall barn – 134 gallons/day Septic tank minimum = 134 x 4 = 536 gal Bark Area (1) is 30 sq ft/cow x 60 = 1800 Bark Area (2) is 134 gal x 8 sq ft = 1072 sq ft Bark Bed 30’ x 36’ Two Bark Strips with chamber system 12’ x 45’ each (min) Pump every other day Goulds Pump—0.4 hp 2” PVC dist’n pipe is openable at one end

Bark Strip Chamber Dist’n: 

Bark Strip Chamber Dist’n

Irrigation System : 

Irrigation System Wastewater is pumped to holding tank in field – lowest elevation Pump to wobbler sprinklers with cool temp. Use impact head >40F System drains back to holding tank

Movable Irrigation Set-up: 

Movable Irrigation Set-up Wastewater goes to septic tank and then is pumped to six month storage Six month storage is irrigated out 1.5” tube Sprinkler line is towed by four wheeler– max is 13 sprinklers-650’ Nozzles <1/8” dia.

For more Information: 

For more Information www.bae.umn.edu/extens/milkhouse Sara Christopherson 612/625-7243 shc@umn.edu David Schmidt schmi071@umn.edu * See irrigation details handout page.