Cumberland is a small town with a big problem…how to dispose of the phosphorus that comes into the wastewater treatment plant from the 2291 citizens of the community. Fortunately, this small municipality has used some innovative resources available to it to solve this problem. They not only have solved their problem, but they have gone over and above their requirements and have been able to go above and beyond. The biggest 2 factors? Common sense and the ability to work with others.

The city of Cumberland is located in Barron County in northern Wisconsin. The city wastewater system has about 916 connections and the level of phosphorus coming into the plant is relatively high as an average. Average total phosphorus loadings to the plant are approximately 8.5-9.0 mg/L. You may think this is a product of industrial discharges, but there are few industries in town that do not treat for phosphorus or that discharge year round. The average discharge from the wastewater treatment plantis around 4-5 mg/L. This results in somewhere around 2200 pounds of phosphorus that is discharged yearly from the municipal plant. The city discharges to the Hay River which is part of the Red Cedar River water basin. This basin takes in about 1900 square miles.

The program that Cumberland put together started in 2001. The city of Cumberland approached the county agriculture department with the idea of trading the cost of treating for phosphorus for farmers enrolling in soil & water conservation practices. This agricultural soil & water conservation program pays farmers a certain amount of money per acre for no till practices, conservation tillage, contour farming, contour strips, feedlot relocation, and soil testing. The county ag department had calculated cost per acre in the following table:

Practice / Cost Share Rate
No Till / $18.50 / acre
Conservation Tillage / $15.00 / acre
Contour Farming / $7.00 / acre
Contour Strips / $10.00 / acre
Feedlot Relocation / 70%
Soil Testing / 50% / max $6 per sample

Table 1. Hay River Watershed/City of Cumberland phosphorus trading project from Barron County 2007 Soil & Water Conservation opportunities pamphlet

These programs were already in place in Barron County. The local County Ag agent, with the cooperation of the city, reached out to the farmers located within the Hay River watershed and encouraged them to sign up into these programs. This involved farmers agreeing to follow the farming practice of their choice, and getting paid the above rates per acre. This had the result of removing phosphorus from the river system with the city paying for the program, and the city using money they normally would spend on removal at the plant (chemicals) supplying the funding to this program.

The city and County Ag department then had to get the Department of Natural Resources to agree to this program. Essentially the biggest concern for DNR with the program was the ratio of agricultural phosphorus pounds removed to municipal phosphorus pounds allowed into the river system. DNR wanted 10:1; for every 10 pounds of agricultural phosphorus removed there would be one pound of municipal phosphorus allowed into the river system. The city negotiated with the DNR and a 2:1 ratio was agreed upon. This negation was helped along by the county Ag agent, the local DNR Basin Supervisor and the state representative from the district.

The results of the trading program since 2001 are shown in Table 2, below:

Year / Acres
No Till / X 3 ton/acre
saved / Acres
Cons. Till / X 2 ton/acre
saved / Pounds
Phosphorus
saved / Cost per
pound / Paid
2001 / 577 / 1731 / 147 / 294 / 6924 / $2.14 / $14,848.75
2002 / 448 / 1344 / 326 / 652 / 7876 / $1.67 / $13,128.00
2003 / 367 / 1101 / 345 / 690 / 7164 / $1.73 / $12,428.15
2004 / 615 / 1846 / 276 / 551 / 9584 / $1.84 / $17,659.45
2005 / 593 / 1780 / 248 / 495 / 9100 / $1.62 / $14,797.40
2006 / 561 / 1684 / 243 / 486 / 8678 / $1.69 / $14,627.20
2007 / 599 / 1796 / 103 / 207 / 8012 / $1.70 / $13,628.60
2008 / 845 / 2535 / 244 / 488 / 12,091 / $1.23 / $14,908.30

Table 2. Cumberland Nutrient Trading Summary

If we look at the summary for 2008, we see that Cumberland spent $14,908.30 on the program which saved 12,091 pounds of phosphorus going into the environment. This $14,908.30 is money that would have been spent at the treatment plant on chemicals to remove 2200 pounds of phosphorus at the plant. The final cost was $1.23 per pound of phosphorus removed in the river basin. It is not known for sure, without further study, but, it is thought by the plant operators that $14,908.30 would not cover the cost of chemicals and land spreading the resultant sludge from the treatment plant.

The above program is essentially removing massive amounts of phosphorus from the environment at a reasonable cost and with cooperation from local DNR and County Agricultural agencies. The acceptance of this type of program across the state would prove beneficial to both farmers and municipalities. But it is the DNR’s stance that treatment plants still have to treat for phosphorus, plus spend money on a program similar to the above which will have to be overcome. The incentive to continue this program for Cumberland is to spend their money on removing the phosphorus from the river system, not at their treatment plant. If systems are to be able to comply with new ultra-low phosphorus limit levels, they have to be given this option.