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HomeMy WebLinkAboutNatural Resources June 1 20041 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. WHATCOM COUNTY COUNCIL Natural Resources Committee June 1, 2004 Committee Chair Sharon Roy called the meeting to order at 9:30 a.m. in the Council Chambers, 311 Grand Avenue, Bellingham, Washington. Present: Absent: Seth Fleetwood None Laurie Caskey- Schreiber Also Present: Barbara Brenner Sam Crawford Dan McShane SPECIAL PRESENTATION 1. REPORT ON LAKE WHATCOM WATER QUALITY AND THE LAKE WHATCOM MONITORING 2002 -2003 FINAL REPORT (AB2004 -228) Dr. Robin Matthews, Western Washington University, stated the report is online at the institute's website. A hard copy is available from City of Bellingham Public Works Department. This year the report includes a review of all data since 1988. Trends are showing that the lake is in a state of transition. Lake Whatcom is long and deep. It is warm monomictic, which means it circulates from top to bottom from fall to spring. There is a mix of surrounding land uses, which makes the water quality issues complex or interesting. It is the primary drinking water for residents of Bellingham. The lake has two shallow northern basins. The shallow basins are about two percent of the total volume of the lake, and the water quality is very different between basins one and two and basin three. The water in most lakes over 25 feet deep in Puget lowlands will mix from the surface to the bottom from fall to spring. During this time, any dissolved chemicals will mix, even in basin three. There is uniform chemistry and temperature. However, in the summer as the surface warms, it forms a top layer that is physically separate. Once it's warm enough, not even a strong windstorm can mix the top layer of the lake. The surface and bottom layers don't mix during the summer, beginning in May or June. That period ends abruptly for basin one and two in Octobers and in November or December for basin three. Because of the multiple use designation, the watershed has impacts from many activities, which creates a number of issues on water quality. Western Washington University (WWU) has been collaborating with the City of Bellingham Natural Resources Committee, 6/1/2004, Page 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. and County since the 1960's on water quality monitoring of the lake. Since 1988, there has been a long term monitoring program. The structure of the program hasn't changed since 1988. The program provides consistent data to look at long term, which is several decades, trends. Lakes age on a geological time frame over thousands of years. Humans can accelerate those changes into decades. Also, they occasionally do short -term projects that are spin offs of the long -term project. Current objectives are to conduct long -term lake and stream monitoring, collect lake and stream hydrologic data, and to evaluate the effectiveness of stormwater treatment systems in watershed. They measure monthly the internal factors and external factors that affect water quality. One test from a lake that would tell the most about the lake would be dissolved oxygen, which predicts almost everything else in the lake. They also measure algae, which forms precursors that form carcinogens. External factors are atmospheric contamination, which they don't measure, and residential development and surface runoff. They collect samples monthly and test for a full suite of nutrients. Annually or semiannually they look at metals. Dissolved oxygen is important because most aquatic life requires it. Dissolved oxygen is oxygen that is dissolved in water rather than atmospheric. A major source of dissolved oxygen is atmospheric oxygen. When summer stratification sets in, the bottom layer doesn't get oxygen. The amount of oxygen that dissolves depends on temperature. Less oxygen can dissolve in the water in the summer. Brenner asked if there are salmonids in the lake. Matthews stated there are Kokanee salmon in the lake, and a hatchery uses the lake for adult fish development. The lake looks different between the north and south ends. The north basin has warm temperatures on the surface, and the bottom layer is colder. From the surface to the bottom of the south end, there is the same amount of oxygen. That is evidence of an unproductive lake that does not have a lot of algae or bacteria. The bottom water has not received new dissolved oxygen. There is only the oxygen that was trapped there during the beginning of the summer. There is not enough life using up the oxygen. In the north end of the lake there is plenty of oxygen at the surface, which is in contact with the atmosphere. Underneath the surface, the amount of oxygen is virtually zero because bacteria are using oxygen at the bottom of the lake. As the bacteria is using up the oxygen during the summer, no more oxygen is coming in. The classic profile at the north end is almost no oxygen, while at the south end there is a lot of oxygen. Natural Resources Committee, 6/1/2004, Page 2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. One of the things she noticed about five or six years ago was that the upper part of the bottom layer seemed like it was losing oxygen. It is. When the lake was first placed on the 1993 303(d) list, it was based on oxygen depletion in the entire lower section. The State Department of Ecology (DOE) determined that the oxygen levels were not dropping near zero, but were dropping faster. That signifies the lake is changing. Dissolved oxygen through time would show that oxygen is significantly lower as time progresses. However, the oxygen level is lower earlier in the year. Lower oxygen is the result of microbial respiration, especially from bacteria. The bacteria are decomposing organic matter, such as dead algae. The algae feeds bacteria. A major cause of lower oxygen is more algae at the surface feeding bacteria at a faster rate. A result of lower oxygen is the loss of habitat. Salmonids require oxygen and cool water. Salmonids seek out deep water as a refuge as the surface gets hot, but this deep water won't be accessible to them because of low oxygen. The unpleasant odors in late fall leaches out of the sediments. There is a release of nutrients and other chemicals from the sediments, particularly phosphorus, which causes more algae to grow, and then causes the oxygen to decline faster, which releases more phosphorus. It's an ecological loop that lakes go through during a transition stage. It accelerates the rate of aging of the lake. Another result of lower oxygen is an increase in the cost of treating drinking water. As increase algae in surface water, there is potential to increase disinfection byproducts in the treated water. Last, a low oxygen environment is associated with the methylation of mercury. Methylation of mercury is done by bacteria grown in anaerobic environments. Once methylated, mercury can be incorporated into the food chain. What is supposed to be causing that oxygen trend is chlorophyll and more algae. If oxygen is being lowered faster, it should be because more algae is fueling that change. However, she didn't see a change in the algae. Oxygen is one of the easiest things to measure. Algae is more difficult to measure. Now, the trend is there. In all the measurements, indicators suggest an increasing trophic state. That means the lake is becoming more productive and can be measured in the space of ten to 15 years, which is not good. It means the lake is changing. The annual report shows amounts of major nutrients. In a lot of the key indicators, they're seeing that the water quality is going the way they would expect. Over the course of the summer, algae uses nutrients, especially nitrates. The level drops during the summer. The nitrate is dropping faster than it normally drops. The rate at which the nitrate is dropping, from algae taking it up, is increasing. Natural Resources Committee, 6/1/2004, Page 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. Caskey- Schreiber asked if they want to keep nitrates out, and if it's good that it lowers during summer. Matthews stated it's not good. One kind of microbe is called blue -green bacteria that can use atmospheric nitrogen, for which there is already a supply. If the nitrate levels drop, they will see the blue - greens increase, which is what they're seeing. The Lake Whatcom blend fertilizer has nitrate, but not phosphorus. If there is excess phosphorus related to nitrogen, they can fertilize with nitrate to encourage the kinds of algae they want, not the blue -green algae. McShane stated she's saying that there are algae in the lake that love nitrates. If running out of nitrates, those algae don't do so well, which gives an ecological advantage to the bad algae. Matthews stated one measure is chlorophyll. From 1995 to 2003, there was no change with time at site one. At sites two through four, there was a significant increase. Alkalinity is another indicator. More productive lakes have more alkalinity in both surface and bottom waters. Another indicator is pH, which is significantly increasing in all surface sites and decreasing in all sites at the bottom. In photosynthesis during the daytime, algae that are photosynthesizing, are temporarily increasing pH. Simultaneously, when algae is decaying, pH will decrease in the bottom later. That's exactly what they're seeing. There are two kinds of algae that are increasing, diatoms and blue - greens. The amount of diatoms is up at all sites. The blue - greens are increasing near the surface. All sites are showing an increasing pattern. The growth of algae in the lake is limited by the amount of phosphorus present. Phosphorus comes from the release during the anaerobic period when the sediments go anaerobic. It also comes from watershed loading. Phosphorus levels have increased since 1981. Diatoms are usually the dominant type of algae in the lake. They can cause taste and odor problems in drinking water treatment. The densities have increased since 1988. Low nitrogen levels encourage blooms of blue - greens. When they chlorinate water with residual organic material, such as algae, there is the potential for more trihalomethane (THM). The level of THM in the treated drinking water has increased, especially from mid - summer to fall. The level is still below the acceptable level for drinking water. Some THM are carcinogenic. One suggestion is that they move the intake into basin three. They collected water quality measurements along Strawberry Sill. The findings show the water quality is similar to basin three, except for total organic carbon (TOC). The highest measurements of TOC in the lake are at this site. Natural Resources Committee, 6/1/2004, Page 4 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. Brenner asked why they would see high TOC. Matthews stated TOC is high because a lot of construction is going on. Also, the local area is a shallow area that produces a lot of chlorophyll. Another issue with moving the intake, which would be very expensive, is that they're seeing lots of movement of water in both directions at this sill. They have been monitoring lake and stream hydrology flow every 15 minutes year- around from three major tributaries. These hydrographs are important for water balance and assessing compliance with the total maximum daily load (TMDL) study. Every year, they create a water balance model. They look at the inputs minus the outputs and change in the storage. The recent droughts have resulted in substantially less input. Brenner asked if it makes a difference that Georgia Pacific (GP) is not taking water anymore. Matthews stated in terms of other losses from the lake, it's hard to put it in perspective. One noticeable change was the change in the diversion from the Nooksack to maintain instream flow. Anderson Creek is no longer a major water source in the summer. (Clerk's Note: End of tape one, side A.) Matthews continued to state that more noticeable is the relative effect of the loss of the diversion during the summer on the water balance in the lake. The loss of GP is harder to assess because it's one of many outflows, including Whatcom Creek. Caskey- Schreiber asked if withdrawing that much water is a simple solution, however it's a misperception to treat the lake more like a river. Matthews stated the reason why they're not diverting as much is to maintain instream flow to protect fisheries. They can't change policy to fix the problem because that will create another problem. Another objective is stormwater treatment. In 1998, the lake was listed for dissolved oxygen problems. Now, they're seeing other trends showing lake increase in productivity. There are two ways to increase productivity, which is due to phosphorus availability. One is from oxygen depletion, when oxygen levels drop and phosphorus leaks out of the sediments to become more available. Other is from watershed sources of phosphorus. They've known for decades that one indicator of residential development is phosphorus in runoff. Residential development carries increased amounts of sediments, nutrients, and pathogens. Brenner asked what from residential development increases phosphorus. Matthews stated the sediment itself has phosphorus. Phosphorus is stuck on the sediment, but it doesn't stay stuck. The algae produces enzymes that pull the phosphorus off the sediment. Any exposed soil or impervious surface that carries deposited sediment can carry phosphorus. There is also pet or animal waste Natural Resources Committee, 6/1/2004, Page 5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. coming from a higher density of animals and also from impervious surfaces. Every residential stream she's ever looked at has elevated phosphorus from many sources. Any activity that disturbs the soil will produce sediment. If sediment management techniques were adhered to and didn't fail, it would help. Even so, there would be elevated phosphorus. They've been measuring three stormwater treatment systems in or near the watershed. The relative contribution of phosphorus in residential streams is 44 to 49 micrograms per liter compared to 9 to 13 micrograms per liter in the forested streams. The levels are similar for pathogens. Pathogens are a human issue, not a water quality issues, other than they are a very good indicator for residential contributions. One issue with coliforms are the human pathogens such as giardia and cryptosporidium, which can be present. Stormwater treatment can reduce pollution going into the lake. Phosphorus is difficult to reduce. It requires a large area of land and advanced technologies. The results are the most unsatisfying in terms of how technology works. Compared to many other lakes in the world, the phosphorus levels are still low. The problem is that the lake is very sensitive to small additions to phosphorus and it gets harder to remove the phosphorus. None of the treatment systems in the watershed are showing any consistent reduction, especially of phosphorus. Other new technologies are being developed. Lots of indicators show that Lake Whatcom is moving toward a higher trophic state. Bacteria are increasing. They are seeing high concentrations of classic stormwater pollutants like phosphorus coming into the lake. Treatment systems aren't effective at a level that they need. Basin three has best water quality and highest oxygen and lowest pollution concentration. However, they are seeing changes. Watershed protection is critical to maintain the quality of the basin. In 1980's, basin two had water quality similar to that of basin three. In the past few years, basin two has become more similar to basin one. Rapid growth in that surrounding watershed and changes in the hydraulic patterns will continue deterioration of that basin. Basin one has the most residential development and worst water quality. The single most important contributor to pollution in Lake Whatcom is stormwater runoff from residential development. Control both internal and external sources of phosphorus. Current problems are from existing, not future, development. The lake is showing that it can't sustain existing development without changing its trophic state. They need to limit the effects of new development and mitigate the effects of existing development. That will be hard to do. Stormwater treatment systems may or may not work. A tough issue is that watershed protection has invisible benefits. Since the lake is already changing and there will still be deterioration, the question is how they justify downzoning large areas of the lake. No one can show the direct measured effect of not putting an extra 1,000 houses in the watershed. It's an invisible benefit that costs a lot. Natural Resources Committee, 6/1/2004, Page 6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. Low oxygen conditions in basins one and two contribute to deterioration. If they reduce the amount of phosphorus in the lake, oxygen depletions in basins one and two will stabilize. However, they can't reverse it. Once they start seeing changes in basin three, it's too late. Caskey- Schreiber stated she's heard theories on how to save the lake. One was to separate basin three with a curtain. Aside from cost and how political that would be, she asked if that has ever been done. Matthews stated she's seen lakes separated, but doesn't know if it's a lake management technique. If it's not coupled with substantial watershed protection in basin three, it would be a waste of money. There may be unknown side effects that may be completely unacceptable. Roy stated they recently had presentations on low impact development standards and treated stormwater onsite. She asked for comments on that process. Matthews stated it's a great idea. Stormwater treatment in her presentation is about runoff off site. If they can force runoff through the ground, they can clean up lots of pollutants. It's not perfect, but that would be the approach she would use as far as having a system that is more likely than not to work. She thanked her students and staff at WWU. Caskey- Schreiber asked for recommendations to stabilize the situation. And whether they should start with stormwater or trying to limit future effects. Matthews stated focus on the future effects. The current effects have caused a change. The future effects will contribute to the changes. Once they have a change in the watershed, it's hard to step back. It's hard to choose one over the other, though. They will still have deterioration from existing development. Roy asked about water treatment. One of the things they hear about is that they can just treat the water if the lake deteriorates. Dr. Matthews mentioned disinfection byproducts that result. There are byproducts from treatment that can be dangerous. Matthews stated that is correct. They can treat a very degraded source of water and make it drinkable for humans. There are a number of issues related to that. It costs more. Generally, it increases health risks and they are accepting a level of degradation of a resource that should not be degraded. The question is whether they really want to allow the lake to reduce to that level. Crawford stated he lived in an area that put in a device that would pump air into the water. He asked if that is a good thing that they should be doing. Matthews stated two kinds of pumps. One is a complete lake de- stratifier. Another type is for aeration for the lower portion of the lake. If they don't break the stratified layer, they can inject oxygen into the lowest part of the lake, and can re- aerate the lake, which has lots of good effects. Natural Resources Committee, 6/1/2004, Page 7 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. Crawford stated he saw a presentation where it costs $1,000 per day to run. Matthews stated they are not good for treatment, just good for localized improvement. They're very expensive. Caskey- Schreiber asked if they would have a positive impact if they were to put a ban on fertilizers that use phosphorus. She asked if phosphorus released is from residential development or from exposed soil. Matthews stated a ban wouldn't hurt, but it would affect a small percentage of the total phosphorus. Fertilizer runoff per se is only one portion of the problem. It's not the most significant portion. Animal waste and sediment particles themselves are more significant. Brenner asked if animal waste is major. Even if they get rid of the people, there will be animals. She asked if it's because the animals are in smaller confined areas. Matthews stated there are animals in a forested watershed, but they are less confined and the water flows through soil rather than directly into a stream. The problem in residential areas is impervious surfaces and a higher density of animals. They still see people clean their piles of pet waste by pitching it into the lake. Fleetwood asked Dr. Matthews' opinion on whether current state of the art in best practices exists, so they can capture it all. Matthews stated that because of the institution of National Pollution Discharge and Elimination System (NPDES) permits in 2000 and that cities now treat their storm discharges as a point source and have to have permits for it, in the last four years, she's seen an explosion of treatment technologies for treating stormwater. They're in a process now where things are rapidly changing. The City of Bellingham is trying things with cartridges of a particular material that will absorb phosphorous. There is potential for technological improvement. However, a lot of the new systems are going in without any thought given to monitoring. They need a systematic approach to make sure technology is working. Also, capacity is a factor. They can't just treat a four -month or six -month storm. When they have a big storm, the load isn't treated at all. Crawford referenced the chart of basin one for dissolved oxygen, which looks like things are getting better. He referenced the chart for phosphorous for certain testing sites. He asked the reason for the trends. Matthews stated methodological changes were made in 1993 and 1994. Note that it goes up and down rapidly. Since 1993, there's a lot less variation in the numbers. Regarding the trends on the figures, they are raw plots. She's heard people don't see a pattern in the trends, but the data serves another purpose. They use the charts to archive the data. The phosphorus trend is strongest from 1993 to the present. Oxygen is still significantly deteriorating. Last year, the lake stratified almost six weeks later than it did this year, so the data doesn't look that bad. This year, it's stratified much earlier. Natural Resources Committee, 6/1/2004, Page 8 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. Crawford stated there's a peak in oxygen in 2002 that was never reached before. The lows in many years get close to zero, but they haven't for a few years. Matthews stated it's not dropping to zero because of instrumental testing methods. Once it drops below two, they're in the anaerobic zone. Caskey- Schreiber asked if two - stroke engines, pesticides, or anything they have regulatory authority over pollutes the lake. Matthews stated WWU doesn't measure for those things. She's seen the data on pesticides from DOE. In terms of the hydrocarbons, she sees data from the City of Bellingham. WWU made the decision to switch its boats on the lake to four - stroke engines. It seems that makes sense for a drinking water source. Fleetwood asked if the lake cannot sustain the current level of development. Matthews stated that's correct, without changing its trophic state, which it's doing right now. Fleetwood asked if stopping development is a necessary condition in order to stabilize or reverse negative trends. Matthews stated it does make sense, unless they can find a magic stormwater treatment system that actually works. Treatment methods don't work at lower levels of phosphorus. Kurt Baumgarten, Planner I, stated it would be interesting to look at the effects of propellers in shallow areas in terms of re- suspending sediments and phosphorus. There have studies that have been done on other lakes. Matthews stated she's never studied it but it's an interesting question. If they re- suspend shallow sediments, which have more plant debris, they give algae and bacteria a second chance to pull phosphorus off of that particle. When modeling phosphorus in a lake, normally the model measures inputs and puts out a sediment trap. Once it settles to the bottom, it's considered lost from a modeling perspective. Those models aren't usually measured for phosphorus settling. In one case where it was modeled, they found that re- suspension was higher than they accounted for, and accounted for a substantial reintroduction of phosphorus into the water column. Crawford stated that seems it would also be a side effect from the aeration methods he mentioned earlier. Matthews agreed. Fleetwood asked if there would still be a chance of continuing this trend toward a trophic state if they implement effective systems to capture stormwater and also stop development. Matthews stated eventually, if they can stop the nutrient input, the lake would stabilize at some level. The TMDL is trying to capture that very question. Roy asked if the TMDL study has begun and when they will see information. Natural Resources Committee, 6/1/2004, Page 9 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 DISCLAIMER: This document contains the Whatcom County Council or Committee minutes, as approved. However, unless an attested signature page is attached, they are not the final approved minutes. Steve Hood, Department of Ecology, stated he'll give a report to the committee in a couple of weeks on the status of the TMDL. OTHER BUSINESS There was no other business. ADJOURN The meeting adjourned at 11:00 a.m. Jill Nixon, Minutes Transcription ATTEST: Dana Brown - Davis, Council Clerk WHATCOM COUNTY COUNCIL WHATCOM COUNTY, WASHINGTON Sharon Roy, Committee Chair Natural Resources Committee, 6/1/2004, Page 10