2002 Annual Report
Research
Dairy Milkhouse Wastewater Treatment
Kevin Janni, Professor
Jun Zhu, Assistant Professor
Sara Christopherson, Extension On-Site Sewage Treatment Educator
David Schmidt, Assistant Extension Engineer
Vern Oraskovich, Regional Extension Educator
Chip Hentges, Carver County SWCD
Funding Source
Minnesota Agricultural Experiment Station; Minnesota Extension Service;
Carver Soil Water Conservation District; Minnesota Pollution Control Agency;
Bongards’ Creameries, Carver Board of Water and Soil Resources; Carver
County Environmental Services; Wright County Soil Water Conservation District;,
Bevens Creek Watershed; Crow River Watershed
Objective
The objective of this project is to evaluate and demonstrate effective
techniques and/or systems to reduce environmental pollution from dairy
milkhouse wastewater and disseminate the results to dairy producers in
Minnesota.
Project Description
Recent revisions to the Minnesota Feedlot Rules (Minnesota Rules Chapter
7020) make it illegal to directly discharge untreated milkhouse wastewaters
to public water bodies. This rule change and greater enforcement has increased
requests for information on how to properly handle milkhouse wastewater
from dairy producers and technical staff from state and federal agencies.
Many Minnesota dairy producers handle manure as a solid and cannot treat
and dispose their milkhouse wastewater through their manure system. Many
small and mid-sized dairy producers do not have environmentally sound
techniques for handling their milkhouse wastewater. For these producers
to be compliant they need cost effective and proven methods for handling
milkhouse wastewaters in a cold climate in ways that meet or exceed regulatory
requirements.
A joint agency task force was created and grant funding was obtained
to design and construct demonstration systems and monitor their performance
in Wright and Carver Counties. Data collected includes milkhouse water
usage, milkhouse wastewater strength, and treatment system effectiveness.
All the wastewater samples will be analyzed for total suspended solids
(TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD),
phosphorus (P), nitrogen (ammonia, nitrate, and total Kjeldahl), pH, and
fats/oils/grease. Sludge depth, solids accumulation, and scum depth will
be monitored in the septic tanks.
Results
Seven out of the eight systems have been installed. Sampling and monitoring of these systems has begun.