There are several minor sources of Bay nutrient pollution other than agricultural fertilization practices and urban discharge/runoff. Agencies often focus on these processes in order to distract the public from the big problems as well as to make the big problems look smaller by “dilution.”
Acid rain contains two acids, sulfuric and nitric. Sulfuric acid mostly derives from burning S-rich coal. Nitric acid is produced by all high temperature combustion processes, especially electric utilities. Nitric acid dissociates into protons and nitrate, and when it rains out, up to 4 or 5 pounds of nitrate can be supplied to each acre each year. To put this in perspective, conventional fertilization releases about 46 pounds of nitrogen per acre per year and the land application of sewage sludge can release more than 400 (Nutrient pollution.) Most acid rain derives from mid-continent combustion and is carried eastward by prevailing winds. There are two reasons why acid rain should be ignored as we try to reduce nutrient pollution of Chesapeake Bay. First, the best way to reduce acid rain is to reduce combustion of fossil fuels. This is a very different problem than agricultural or urban nutrient discharge into the Bay and needs to be addressed as greenhouse gas emissions are reduced country- (world-) wide, not just in the Bay watershed. And second, little can be done locally to reduce acid rain since most of it derives from outside the Bay watershed. Only insignificant amounts of acid rain are “locally actionable” and society is better served if our limited resources to address abysmal Bay water quality are targeted at pollution from agricultural fertilization and urban discharge.
Homeowner fertilization certainly contributes pollution, especially when chemically maintained lawns exist close to the water. There exist great differences in estimates of the amount of pollution caused by landscape fertilization. Few people would advocate that homeowners fertilize their properties at the rates used to grow corn and small grain, on the order to 160 pounds of nitrogen per acre. How many people apply 32 (160 / 5) 50-pound bags of 10-10-10 each year to each acre their property? This, and the fact that more acreage is farmed than is landscaped, means that homeowner fertilization is not a major source of Bay-wide pollution. There is certainly need to educate people not to over-fertilize and to fertilize at the right time of the year, especially for lawns. A tax on fertilizer would be appropriate if the money was directed at Bay restoration and not just handed out to the politicians. “Every little bit helps” but addressing homeowner fertilization practices won’t significantly improve Bay water quality, and could actually be harmful if it dilutes efforts to reduce the two major sources of pollution.
Septic systems can be a source of nitrate pollution if not properly installed and maintained and if adequate riparian buffers (mature trees and ground cover) do not exist between the drainfield and the nearest water. Most phosphorus discharge does not reach the groundwater because it is temporarily sequestered in the soil. The Virginia Health Department conducts periodic “shoreline surveys,” literally walking the shoreline looking for problems. Virginia coastal plain counties are just now getting around to mandating the periodic septic system inspection and pump-out that the 1988 Bay Act requires. Although continued citizen education is desirable, additional programs intended to reduce a miniscule source of pollution are not warranted.
These facts, and the small amount of pollution contributed by all these sources to the Bay compared to agricultural fertilization practices and urban discharge/runoff, mean that significant amounts of resources should not be wasted to address these issues. Even if all these issues were addressed as much as possible, they would have such a small effect on improving Bay water quality as not to be noticeable. Efforts must focus on the biggest sources of pollution, agricultural fertilization practices and urban infrastructure. The problems outlined above are merely quantitatively insignificant distractions.