In 1913 the City of Milwaukee created a sewerage commission charged with the responsibility of cleaning up the waterways. That same year, a chemist in England was experimenting with the biosolids in sewage sludge. Air was allowed to bubble through wastewater for a period of time. When the air was turned off, and the mixture settled, the water was purified. This was the beginning of the activated sludge process.
The Milwaukee Sewerage Commission's laboratory studied the new process and formally adopted it for use on December 31, 1919. In 1921 interceptor sewers were installed to connect to municipal sewers, which enabled all wastewater treatment to be completed at a central location. Jones Island, on the shore of Lake Michigan, was chosen for that site, and in 1923 construction began on the first large scale activated sludge plant in the world. In 1974, the Jones Island Wastewater Treatment Plant was named a National Historic Engineering Site by the American Society of Civil Engineers.
Enter O.J. Noer
The major problem with this new sewerage treatment process was the production of solids – the microbes left over from the treatment process. For a city the size of Milwaukee, this meant that between 50,000 and 70,000 tons of dried microbes needed to find a home. Land-filling this waste was expensive and wasted a valuable resource.
In the early 1900’s, the Sewerage Commission established a fellowship at the University of Wisconsin College Of Agriculture under the direction of Professor Emil Truog to investigate uses of activated sludge as a fertilizer. O.J. (Oyvind Juul) Noer was named as the fellow to carry out the work.
Noer determined that the average nutrient analysis of the material was 6.2 percent total nitrogen, with 5.17 percent being water insoluble nitrogen (83% WIN); 2.63 percent available phosphate (P205) and 0.4% soluble potash (K20). In his literature review, Noer found that the available nitrogen generally resembled so-called high grade organic nitrogenous fertilizers and gave superior growth results compared to manures and chemical fertilizers of the time.
After experimenting with field crops and vegetables, Noer experimented with the use of this organic nitrogen fertilizer on golf courses and found it superior and one-third the cost of other fertilizers commonly used at the time. Additionally, it provided two distinct advantages: first, there was no danger of burning the turf even with over-application; second, it produced a dark green dense turf without causing excessive top growth.
Initial test plots were developed at Blackhawk Country Club and Maple Bluff Country Club in Madison, Wisconsin. Plots were subsequently established in Chicago, Detroit, St. Louis, Cleveland, and St. Paul. As word spread among golf course superintendents across the country about this new organic nitrogen fertilizer, Noer knew he had a commercially viable product. In 1925, the Sewerage Commission concluded that the disposal problem they faced could be solved by producing and marketing the fertilizer.
Of course, any commercial product needed a name. In 1925, a contest to name the new organic fertilizer was advertised in the National Fertilizer Magazine. First prize was awarded to McIver and Son of Charleston, South Carolina for their entry "Milorganite," derived from MILwaukee ORGAnic NITrogEn. Now with a name and an identity, the Sewerage Commission began marketing Milorganite in late 1925. By the end of 1926, about 5,500 tons was inventoried, with orders placed for 2,500 tons.
By the mid-1930's, production hit 50,000 tons, selling for up to $20 per ton, and production could not keep up with demand. At that time, most Milorganite was sold to fertilizer companies for blending with other Nitrogen-Phosphorus-Potassium (N-P-K) sources, and very little was sold into the specialty fertilizer market.
Research continued through the mid-1930's, with Noer establishing a soils lab at the Milwaukee Metropolitan Sewerage District to aid his studies. This was the first soils lab established exclusively for turfgrass. Through his work in the lab, Noer pioneered much of the methodology used in modern labs, including sampling depths and techniques, as well as laboratory procedures. Additionally, Noer determined through clipping analysis that the basic nutrient ratio in plant tissue was 3:1:2 (Nitrogen: Phosphorus: Potassium) instead of the 1:4:2 originally thought. From these studies came the basic Milorganite fertilization recommendations. These recommendations have stood the test of time and still fit well, even in the low nitrogen fertilization programs commonly used in modern turf management regimes.
Cleaning-up Our Waterways - Heavy Metal Reduction
In the early 1980’s there were concerns with the level of some non-nutrient metals (Cadmium, Chromium, Lead, Mercury, Nickel,) in Milorganite and the Milwaukee waterways. As a solution, the Milwaukee Metropolitan Sewerage District established a number of pretreatment policies and put in place monitoring systems that dramatically reduced the volume of metals ending up in the region’s wastewater leading to huge reductions in Milorganite fertilizer. The 2012 Source Reduction Effectiveness Analysis (p27-33) displays the historical reduction of metal concentration levels from 1975-2011.
Over the years, Milorganite has adapted to market changes. In 1926, most of the Milorganite was sold in bulk, but by the mid-1930's it was also packaged in 25, 50 and 100 lb. bags. In 1955, packaging changed to offer 40 and 80 lb. bags and again in the 1970's as 20 kg bags were introduced with the movement to metric in the U.S. Today Milorganite is sold in a distinctive 36 lb. bag and a 5 lb. bag exclusively for the retail market, 50 lb. bags for the professional market, and reusable bulk bags for large area applications. The blending market continues to be important as other companies find the nutrient analysis to be a valuable addition to their products.
Sound, practical agronomic research continues to be a top priority. Milorganite has been included in and has helped fund many important research projects at universities across the country. Areas of interest include nutrient leaching and run-off, the effects of different fertility regimes and sources on irrigation requirements, and the effect of Milorganite phosphorus in the environment.