It has been known for decades that the point-source discharge from wastewater treatment plants is an easy source of pollution to address. The technology to significantly reduce the nitrate and phosphate concentrations in the wastewater stream has existed for decades, and is constantly being improved. Wastewater treatment plants were originally designed to remove pathogens and offensive odors from contact with the public. Only subsequently has the need to address nutrient pollution been addressed seriously by sanitary engineers. Wastewater treatment plants, like septic systems, return the nutrients used to grow the food we eat back to the environment.

Why wasn’t this problem addressed decades ago? The fundamental reason (Why hasn’t Chesapeake Bay improved?) is that people have not been willing to pay for the increased service and government, especially EPA, has not mandated that they do so. This is a classic example of EPA protecting the Economy and not the Environment. It is important to understand that reducing the release of nutrients from the pipes of wastewater treatment plants will have an immediate effect in improving water quality. Just as sanitary engineers were forced to reduce nutrient release from wastewater treatment plants in addition to achieving their original goals (odor and pathogen control), agronomists must change their mind-set and recognize that farm profits are not their sole goal. Agricultural pollution causes real costs to society, and agronomists must become more concerned about the welfare of society and not just the bottom line for individual farmers.

Nutrients are returned to the environment from wastewater facilities in three forms: 1) as gasses like ammonia and NOx’s (all pollutants), and diatomic nitrogen, 2) dissolved in the wastewater, and 3) in the sludge. The Blue Plains wastewater facility of the DC Water and Sewer Authority (www.dcwasa.com) purports to “Serve the public and protect the environment.” It generates about 1000 (wet) tons of sludge each day, lime-stabilizes it, and land applies it. If the 365,000 tons/year were landfilled at a cost of $30/ton for tip fees, the cost to the 2,200,000 customers would be about $11,000,000. Each customer would see their annual bill increase by no more than $5, the equivalent of two bags of junk food, each year.

The often-touted economic benefit of land application of sewage sludge for farmers must be balanced against the alternatives. In Virginia, according to a Joint Legislative Audit and Review Commission (JLARC) Report #89 (jlarc.state.va.us), municipal sewage sludge is spread on 50,000 acres annually, out of about 4,300,000 acres farmed in Virginia. The vast majority (about 99%, or 425/430) of Virginia farms are obviously profitable without using sewage sludge in lieu of chemical fertilizer. The average saving, about $56/acre according to the JLARC report, means the total saving for farmers, state wide, is about $3,000,000 each year. The recreational value of Chesapeake Bay and citizen’s “willingness to pay” to improve water quality vastly exceeds $3 million each year by any estimate (e. g., the article by R. Hanmer in the October 2004 Bay Journal - www.bayjournal.org.) In Virginia alone, banning the land application of municipal sewage sludge would keep about 4.4 million pounds of nitrogen from being disposed on fields to no benefit of crops. As reported in the February 2007 Bay Journal, the cost of upgrading the Blue Plains wastewater treatment plant to eliminate a similar amount of nitrogen discharge will be between $500 million and $1 billion! The economics are crystal clear. The cheapest way to increase agricultural fertilization efficiency and eliminate a massive source of pollution of Chesapeake Bay is to ban the land application of animal waste. In the case of sewage sludge, the increased cost would have only a minor effect ($1,173 per farm according to the JLARC report) on a very few (5/430) farmers, and would require an inconsequential increase in a large number of people’s wastewater bills. I addressed these issues in articles in the December 2006 and May 2007 Bay Journal.

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