The average dairy cow weighing about 1,400 pounds excretes about 120 pounds of waste per day, and the average farm spans from anywhere from 1,000 to 5,000 dairy cows. Therefore, since the majority of dairy farms around the country use confined animal feeding operations where the animals don’t leave the barnyard that waste is not naturally spread on pastures and has to be picked up stored and then later removed from the farm. The way that this is being done needs to be changed in order to create a healthier planet.
The green revolution has allowed farmers all over the country to modernize and mechanize their practices to increase yields and profits. The dairy industry is no different and has also progressed in many ways to increase production and met the needs of the growing population. Innovations that the dairy industry has seen include; high tech milking machines, pasteurization techniques that allow our milk to be cleaner, an advanced understanding of the dietary needs of lactating animals in order to produce the most amount of milk possible, and much more (Kompas). All of these things have made the industry more productive. However, as this has gone on the number of dairy animals on each farm has dramatically increased and the number of dairy farms has decreased (Kumbhakar). This is because smaller dairy farms are no longer profitable due to how milk is sold on the market. Milk is sold in hundredweights; meaning the price per hundred pounds of milk, and due to the fact that this is a global market price that is always changing it has become more profitable to have a bigger dairy (Cakir). Which in turn has caused producers to take their animals off pastures and into the barn at all times which creates the problem of what to do with our waste.
When it comes to waste collection on the dairy farm many dairy farms use lagoons to store their waste. Every morning and every evening while the animals are being milked farmers clean out their barnyards and sweep all of their waste into lagoons. Once the lagoon is filled up farmers then deal with it by either hiring a service to remove it and they turn it into fertilizer, or big farms buy the equipment themselves and carry out this process on their own. However, with this there are two issues that can occur with lagoons. The first issue is groundwater contamination. As this study done by the Journal of environmental health shows that groundwater by dairy feedlots have higher levels of nitrate, ammonia, chloride and nitrogen (Arnold). The second issue is the methane released into the atmosphere from these lagoons as they sit there waiting to be delt with. In fact, on a hot summer day, lagoons can become a large source of methane gas into our atmosphere (Todd).
When diving into this issue, I reached out to two dairy farmers to see how they deal with these problems. The first one was Michael Montgomery from Mountain Flower Goat Dairy in Boulder Colorado. When discussing to them what they do with their animal waste he told me “that they try to deal with it in the most environmentally friendly way possible”. On their farm, they spend some time every morning spreading out their waste onto their fields that are in fallow. Meaning that they rotate their pastures in a way that after they spread their waste on the field it has a year off to incorporate into the soil so they can grow feed on it the following year. They also take their dairy goats out of the barnyard every day to graze on those said pastures. Therefore, they completely reduce lagoon emissions and groundwater contamination because they don’t have any lagoons on their farm.
The second dairy farmer I interviewed was Carrie Mess, a Wisconsin dairy farmer. When talking to her I asked her how they deal with their lagoons, she explained that “once it fills up, we hire a company to come pump it out”. However, as we continued our discussion, she talked about how it can be very expensive to pump out especially during years with above than average amount of rainfall. This is because it has to be removed a more frequently due to the fact the rainwater will fill up the lagoon instead of animal waste. She also mentioned how around the lagoon in the summer it tends to be really hot due to the methane being released into the atmosphere. Then when talking about potential groundwater contamination we discussed the multiple times they’ve had to replace the liners at the bottom of their lagoons. Due to the fact that every few years the liner begins to fall apart, or the state regulations have changed.
Yes, when addressing the issues that occur around lagoons the Mountain Flower Dairy is the best approach. Which is to not have one. However, they are a lot smaller dairy farm than average and have enough land to have their goats out to pasture. Big dairy’s, in which have over 1,000 cows can’t take this approach due to the number of acres they’d need to support their herd. Therefore, they have to use lagoons. Recently over the last couple years biogas has gained popularity due to Smithfield’s (pig producer) deal with Dominion Energy. By capturing the methane released from lagoons we can use it as natural gas to create energy and also reducing the amount of methane emissions being released into our atmosphere (Purdy). Therefore, making the farmer not only a dairy producer but also an energy producer of renewable natural gas. Where they can make a little extra income so they can afford to remove their waste more often and be able to afford more effective liners for their lagoons to keep their groundwater clean.
Works cited
Arnold, Stephen D., and Edward A. Meister. “Dairy feedlot contributions to groundwater contamination.” Journal of environmental health 62.2 (1999): 16.
Cakir, Metin, and Joseph V. Balagtas. “Estimating market power of US dairy cooperatives in the fluid milk market.” American Journal of Agricultural Economics 94.3 (2012): 647-658.
Kompas, Tom, and Tuong Nhu Che. “Technology choice and efficiency on Australian dairy farms.” Australian Journal of Agricultural and Resource Economics 50.1 (2006): 65-83.
Kumbhakar, Subal C., Soumendra Ghosh, and J. Thomas McGuckin. “A generalized production frontier approach for estimating determinants of inefficiency in US dairy farms.” Journal of Business & Economic Statistics 9.3 (1991): 279-286.
Purdy, Andrew, et al. “Towards sustainable farming: feasibility study into energy recovery from bio-waste on a small-scale dairy farm.” Journal of Cleaner Production 174 (2018): 899-904.
Todd, R. W., et al. “Methane emissions from southern High Plains dairy wastewater lagoons in the summer.” Animal feed science and technology 166 (2011): 575-580.
