Management of Non-Point Source Pollution CE 296B

Management of Non-Point Source PollutionCE 296B Department of Civil Engineering California State University, Sacramento Lecture #1, January 27, 1998 Introduction

I. What is non-point source pollution? Before we define non-point source pollution, let us define water pollution. A. To define water pollution: 1. Start with a water body, an ocean, a bay (saltwater), a coastal marsh, a river, a lake, a stream (tributary to a river), and anything else a canoe will float on. The canoe bit comes form the common law definition of a navigable water body of the U.S. (something that will be important as the course goes on).

I. What is non-point source pollution? (cont.) • A. To define water pollution: (cont.) 2. Associated with that water body is a set of beneficial uses. Those beneficial uses can be: • historical uses • current uses • potential uses 3. Beneficial uses are typically such things as: • sport fishing / commercial fishing • navigation • non-contact recreation / contact recreation

I. What is non-point source pollution? (cont.) • A. To define water pollution: (cont.) 3. A polluted water body is a water body where one or more beneficial uses are not fully realized because of human activities. 4. A pollutant is a substance that when added to the water body by human activities could, if enough is added, cause one or more beneficial uses to not be fully realized.

Discussion Break • The sediment from Mt. Saint Helens erupting substantially impairs the beneficial uses of several water bodies in the region. That is not, in a legal sense, pollution. However, if you are a fish in one of the affected streams, that is definitely pollution. • Sediment is deposited in a stream near a construction site when run-off carries material from disturbed ground. If those sediments could possibly cause an impairment in beneficial uses in the future, that is, in a legal sense, pollution.

I. What is non-point source pollution? (cont.) • A. To define water pollution: (cont.) 5. Thus, for the purpose of this class, water pollution is: • Substances added to a water body • As a result of human activities • That contribute to the loss, or potential loss, of the perceived beneficial uses of that water body. (Note the use of the word perceived, based on ones value system, these beneficial uses could change quite a bit.)

I. What is non-point source pollution? (cont.) B. The most general way in which water pollution is categorized is how the negative effect on the water body is manifested. Two possibilities: 1. The negative effect of the pollutant is based on the concentration of pollutant in the water body in question. 2. The negative effect of the pollutant is based on the mass loading over time of the pollutant in the water body in question.

I. What is non-point source pollution? (cont.) C. The next level of pollutant categorization is what type of pollutant it is. Six possibilities: 1. Biostimulants - BOD, nutrients 2. Sediment - clay, silt, sand, gravel 3. Synthetic organics - e.g. solvents 4. Toxic inorganics - e.g. metals 5. Pathogenic organisms - viruses, bacteria, protozoa 6. Trash - use your imagination

Discussion Break Note that a significant problem is already apparent. Although there are pollutants that only can have negative effects, examples being lead and many synthetic organics, many pollutants can have both positive and negative effects. Examples include: • Sediment: Choked stream beds vs. beach material replenishment • Nutrients: Eutrophication vs. required nutrients

I. What is non-point source pollution? (cont.) D. How do we differentiate between point and non-point source pollution? First, some definitions that make sense from a scientific, not legal, perspective. 1. A point source is a single entry point for a water source influenced by human activity to enter a water body. Further, it is reasonable to have a measure of control over that water.

I. What is non-point source pollution? (cont.) • D. How do we differentiate between point and non-point source pollution? First, some definitions that make sense from a scientific, not legal, perspective. (cont.) 2. Examples of “true” point source discharges include: • A waste water treatment plant. (single point, reasonable ability to control quality) • An industrial discharge

I. What is non-point source pollution? (cont.) • D. How do we differentiate between point and non-point source pollution? First, some definitions that make sense from a scientific, not legal, perspective. (cont.) 3. Non-point sources enter a water body through multiple or undefined locations. Further, it is difficult to have a measure of control over the discharge.

I. What is non-point source pollution? (cont.) • D. How do we differentiate between point and non-point source pollution? First, some definitions that make sense from a scientific, not legal, perspective. (cont.) 4. Examples of non-point source pollution include: • Air pollution reaching a water body • Storm drain outfalls • Run-off, both irrigation return flow and stormwater run-off from agriculture

I. What is non-point source pollution? (cont.) E. Thus, non-point source pollution is substances influenced by human activity that enter a water body through multiple or undefined points of entry. Traditionally, it is difficult to control the quality of those discharges. Finally, those substances must have the potential to negatively influence the beneficial uses of the water body is question.

I. What is non-point source pollution? (cont.) F. Earlier, if was mentioned that our definition of non-point source pollution was a scientific, not legal one. What is an example of where scientific and legal definition diverge? Under the Federal Clean Water Act (CWA), and the associated regulations issued by the U.S. EPA, storm drain outfalls are considered point source discharges. (Much more on this subject matter later.)

II. What are the relative dimensions of point and non-point source pollution (use the “scientific” definition of non-point source pollution)? A. In the February, 1996 issue of National Geographic, a figure of up to 80% of water pollution is of a non-point source nature in the U.S. was quoted. This is a widely quoted figure and never seems to have a citation lineage associated with it.

II. What are the relative dimensions of point and non-point source pollution? B. In reality, this question is much more complicated. Consider the water body - Santa Monica Bay (SWB). 1. On an annual average basis, the flow from the Hyperion Wastewater Treatment plant is 100 times larger than all non-point source flows combined. 2. Due to the greater flows, the mass loadings of most pollutants on SMB is dominated by point sources.

II. What are the relative dimensions of point and non-point source pollution? • B. In reality, this question is much more complicated. Consider the water body - Santa Monica Bay (SWB). (cont.) 3. However, if only near shore areas are considered, the concentration effects are dominated by non-point sources. 4. But, in any given year, those effects are noticeable for eight days. Much debate has taken place on how bad that is.

II. What are the relative dimensions of point and non-point source pollution? • B. In reality, this question is much more complicated. Consider the water body - Santa Monica Bay (SWB). (cont.) 5. When it comes to the effect of mass loadings in near shore areas, consensus on the relative contributions of point and non-point sources is a long way off. 6. A complicating factor is that until recently, sewage entering SMB received little or no treatment.

II. What are the relative dimensions of point and non-point source pollution? C. An example on the other side of the spectrum would be the Sacramento - San Joaquin Delta. 1. Although during the dry season, over 1/5 the flow of the Sacramento River is wastewater treatment plant effluent, it is fair to say that the majority of the pollutants reaching the Delta are of a non-point source origin. This is true for both concentration and mass loading effects.

II. What are the relative dimensions of point and non-point source pollution? • C. An example on the other side of the spectrum would be the Sacramento - San Joaquin Delta. (cont.) 2. However, it is widely believed that the majority of the pollution reaching the Delta is of agricultural origin. In terms of regulating those discharges, the CWA has placed them off-limits.

II. What are the relative dimensions of point and non-point source pollution? D. Therefore, it should be somewhat obvious that assessing the effect of non-point source pollution on many, if not all, water bodies is a difficult task. E. Even more importantly, assessing the effect of efforts to manage non-point source pollution on a given water body is an exceptionally difficult challenge. F. If the public is to pay for these efforts, they would like to see some benefit.

III. The direction this class will take. A. First, we will examine the legal and regulatory framework that efforts to manage non-point source pollution fit into. B. Second, we will investigate how non-point source pollution occurs. C. Third, we will make an attempt to asses how non-point source pollution affects receiving water quality and how receiving water quality changes affect beneficial uses.

III. The direction this class will take. (cont.) D. Fourth, we will examine strategies for the management of non-point source pollution. Those strategies fall into two broad categories: 1. Management efforts directed at the “front of the pipeline”. (Good housekeeping and source control efforts) 2. Management efforts directed at the “end of the pipeline”. (Treatment steps)

III. The direction this class will take. (cont.) E. Fifth, we will investigate techniques for assessing: 1. The costs of implementing efforts to manage non-point source pollution. 2. The benefits that accrue to society from efforts to manage non-point source pollution. 3. Implications of comparing costs to benefits for the management of non-point source pollution.

III. The direction this class will take. (cont.) F. Sixth, and finally, we will investigate issues that are, or will have, an impact on non-point source pollution issues. 1. The views and efforts of the environmental community. 2. Legal and regulatory efforts that are just beginning to have an impact: a. The portion of the CWA that seeks to set “total maximum daily loading” b. The next phase of regulations being debated now

Management of Non-Point Source Pollution CE 296B