1 Management of NonPoint Source Pollution CE 296

1 Management of Non-Point Source Pollution CE 296 B Department of Civil Engineering California State University, Sacramento Lecture #15, March 31, 1998 Receiving Water Impacts - Part II

2 III. Alternative method of assessing receiving water impacts - environmental indicators. A. As discussed last time, a traditional method for assessing receiving water impacts does a poor job of giving us an overall picture of the true state of the receiving water health. 1. What has been advocated by some is to take a holistic approach where the sum of many different aspects of the watershed are simultaneously examined to yield a picture of water quality and where the weak links are in terms of improving water quality.

3 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) A. As discussed last time, a traditional method for assessing receiving water impacts does a poor job of giving us an overall picture of the true state of the receiving water health. (cont. ) 2. A major motivation for developing the idea of environmental indicators was that it seemed impossible to ever collect enough samples to determine receiving water impacts in a traditional manner. 3. A major goal was to monitor in ways other than just collecting samples and analyzing.

4 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) Disclaimer - What you are about to see is taken largely from one groups vision of what an alternative methodology for assessing receiving water impacts. That group is the Center for Watershed Protection. It is a non-profit organization based in Maryland receives most of it’s funding from U. S. EPA. There are other ideas out there on the use of environmental indicators.

5 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) B. The idea behind environmental indicators is to examine simultaneously several different aspects of the watershed that if done intelligently will: • Help identify the root cause of what is causing noticeable pollution effects to a water body. • Help devise strategies that will be useful for many watersheds. • Give warning to situation of a water body that is about to become polluted.

6 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) C. A proposed scheme is to have six indicators of watershed health to be We will examined. They are: focus on these • Water Quality Indicators • Physical and Hydrological Generic Measures of Indicators Receiving • Biological Indicators Water Health • Social Indicators Measures of • Programmatic Indicators Management • Site Indicators Program.

7 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) D. To examine this concept, we will first look at the four indicators that are generic measures of receiving water health. We will then look at how indicators from different groups relate to one another. Finally, we will examine how these indicators might be used to develop strategy for the improvement of a receiving water.

8 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) E. Water quality indicators. The goal of these indicators is to establish a picture of the chemical composition of the water body and the discharges to that water body. In keeping with the concept of gathering an overall picture of the watershed, the frequency of sample would not be anywhere as often as in a traditional approach. I key idea for most of these is to capture normal conditions.

9 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) E. Water quality indicators. (cont. ) 1. Water quality pollutant monitoring. One would select appropriate choices from: • • Water quality pollutant constituent monitoring Toxicity testing Non-point source loadings Exceedance frequencies of water quality standards • Sediment contamination • Human health criteria

10 • • Water Quality Pollutant Constituent Monitoring Completed in the receiving water. Establish under normal conditions: – What the overall chemical quality is. – What pollutants are present. – What the concentration ranges might be. Possibly look at seasonal variations of crucial parameters such as dissolved oxygen. Establish a baseline of data. Within the scope of using a broad base of environmental indicators, crucial not to read “too much” into the numbers.

11 Toxicity Testing • Standard toxicity tests conducted on non-point source runoff, either at full strength or diluted. • Quality of data is likely to be limited, particularly since most toxicity tests currently focus on acute rather than chronic conditions. • May be good for pointing particularly toxic constituents. Helpful in targeting constituents that have priority.

12 Non-Point Source Loadings • Use existing models to estimate non-point source loadings. • Quality of models are limited. Results can only be used as providing a general estimate, with a huge 95% confidence interval, of how much is reaching receiving waters. • May be useful in assessing the impact of new development in a water shed.

13 Exceedance Frequencies of Water Quality Standards • A measure of how often, when, and by what, but not for how long, water quality objectives are exceeded. • Useful in determining during what types of occurrences, small storm, flood events, dry weather flow, etc. , problems occur. Possibly give insight as to reasonable course of action. • May possibly give rise to a more thoughtful examination of beneficial uses and associated water quality objectives. Example, is it, for most cases a good thing that streams are turbid during flood events.

14 • • Sediment Contamination Intelligently sample and analyze sediments for pollutant concentrations. Typically, this does not have to be done very often. Yields some information, although quite imperfect, about the health of an ecosystem. If done very carefully, may yield a good historical record of pollutant loadings. Yields information about what bodies of water have received the largest pollutant loads.

15 Human Health Criteria • Little work that has the possibility of a real impact has been done in terms of assessing human health criteria. • Limited to MCL’s for chemicals and flawed indicator organisms for pathogens. • Is however, the primary motivation behind the establishment of beneficial uses. Clearly, more thoughtful work is required here.

16 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) E. Water quality indicators. (cont. ) 2. Physical and Hydrological Indicators. One would select appropriate choices from: • • • Stream widening / downcutting Physical habitat quality Changes in dry weather flow rates Increased flooding frequency Stream temperature monitoring

17 • • Stream Widening / Downcutting Involves establishing a reference cross-section of a stream and measuring the changes in that crosssection annually. Provides a measure of how land use changes upstream are affecting the integrity of the stream in question. Has a “close the barn door after the horses have been let out” quality. May be used to assess potential impacts of similar land use changes in other watersheds. Is very inexpensive to perform.

18 Physical Habitat Quality -I • Involves surveying the area directly adjacent to the water body to measure for a stream, the amount of: – Channel stability – Channel cover – Instream sediment imbeddedness – Riparian habitat Similar measures for a lake: – Submerged aquatic vegetation – Percent littoral dominance – Shoreline development

19 Physical Habitat Quality -II • Helps provide concrete numbers with respect to cost for any effort to engage in stream restoration. • Relatively inexpensive process. • Has the added benefit of educating the discharger and regulator as to what is actually there. • Does require careful supervision of personnel conducting surveys. What constitutes valid riparian habitat is a matter of some difference of opinion. Quantifiable standards are not well developed.

20 Physical Habitat Quality -II • Helps provide concrete numbers with respect to cost for any effort to engage in stream restoration. • Relatively inexpensive process. • Has the added benefit of educating the discharger and regulator as to what is actually there. • Does require careful supervision of personnel conducting surveys. What constitutes valid riparian habitat is a matter of some difference of opinion. Quantifiable standards are not well developed.

21 • • • Changes in Dry Weather Flow Rates The idea is to compare current dry weather flow rates with “natural” dry weather flow rates to measure the impact of land use on the water body. Moderately inexpensive process, records may already be available. In humid climates, urbanization reduces dry weather flow rates due to decreased ground water recharge. In dry climates, urbanization increases dry weather flow rates due to increased irrigation. In dry climates, many open range practices such as logging and cattle grazing decreases dry weather flow rates due to decreased ground water recharge.

22 Increased Flooding Frequency • Similar to the stream widening / downcutting indicator. Provides a measure of the effect of urbanization on stream hydrology. • Relatively inexpensive to perform. Records are already available. Does have the potential for difference in perception from one reviewer to the next on what constitutes a flood. • Has a “close the barn door after the horses have been let out” quality.

23 Stream Temperature Monitoring • Stream temperatures are measured continuously in an automated fashion. Are then compared to: – Beneficial uses, particularly fish requirements. – A relatively undisturbed similar reference stream. • Provides a direct measure of land use on a easily understood water quality parameter that does have a clear impact on many beneficial uses. • Is an inexpensive way to gather continuous information about a water bodies quality.

24 Discussion Break What physical and hydrological feature that has had profound impacts on streams, particularly in the western U. S. has not been covered? How might that feature be incorporated into an environmental indicator.

25 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) E. Water quality indicators. (cont. ) 3. Biological Indicators. One would select appropriate choices from: • • • Fish assemblage analyses Macro-invertebrate assemblage analyses Single species indicators Composite indicators Other biological indicators It is important to note that these indicators are a particularly direct measure of beneficial use attainment.

26 Fish Assemblage Analyses - I • A resident fish community, as complete as possible, is collected using electrofishing or seining. If possible, multiple habitats in the same water body are sampled. • Fish are counted by: – Number and type of different species present – Total fish present • Biodiversity type indices are used to assess the biological health of the system. These indices have such names as: – Index of Biotic Integrity – Index of Well Being

27 Fish Assemblage Analyses - II • If a pristine reference stream is available, this is a particularly powerful method for assessing the health of a water body. • The number of different species typically found in a fresh water body make this a reasonable tool. In a salt water body, directly connected to the ocean, nobody has come up with any reasonable index to use. • The use of this tool requires considerable expertise, but it’s use is a great good will builder.

28 Macro-Invertebrate Assemblage • Using similar techniques and ideas as the fish assemblage, assess the species diversity and total numbers of macro-invertebrates (aquatic insects). • Is less expensive to perform than fish assemblages and due to the short life span of insects, impacts of non-point source pollution are observed sooner. • One does need to be careful in interpreting data, particularly after substantial flow events which can in the short run have a large negative impact on invertebrates.

29 Single Species Indicator -I • A single species that is known to be particularly sensitive to ecological changes is selected and counted regularly. • Is less expensive to perform assemblages of any kind. • The reaction of the public is bound to be stronger with such an indicator. Two polar reactions: – The decline in trout numbers means that serious action must be taken. – The use of such an indicator is nothing more than a device to stop development of any kind.

30 Single Species Indicator -II • The kind of species most likely to be chosen also have migration patterns, possibly distorting results. • Reasons completely divorced from pollution effects can severely change the numbers of a single species. A classic example was the introduction of the European Brown Trout into U. S. waters. Native species such as Rainbow or Brook Trout were often displaced.

31 Biological Indicators - I • This is “going nuclear” on the use of assemblages. Assemblages of several different groups of living things are simultaneously examined. Included would be: – Fish – Macro-Invertebrates – Micro-Invertebrates (nematodes, etc. ) – Algal Communities • Very expensive, requires substantial expertise to interpret.

32 Biological Indicators - II • If done carefully, could be used to direct less expensive future efforts. One might learn: – What kind of chemical monitoring would be most useful – What kind of toxicity tests would be most useful – What assemblage (fish or macro-invertebrate) would be most useful

33 III. Alternative method of assessing receiving water impacts - environmental indicators. (cont. ) E. Water quality indicators. (cont. ) 4. Social Indicators. One would select appropriate choices from: • • Public attitude surveys Industrial / commercial pollution prevention Public involvement and monitoring User perception These are indicators that give an indication as to how much support can be expected in the long run for the management of nonpoint source pollution.

34 Discussion Break Recalling the Pogo Cartoon of old. “We have met the enemy and it is us” or a more erudite version “The fault dear Brutus is not in our stars but ourselves”, why might these social indicators be crucial to the success of a non-point source management program?