The Water Quality of Froggy BottomsEwan Shortess, Honors ScienceJune 20, 2012AbstractThe objective was to find out if the water quality of Froggy Bottoms was sufficient tomake Froggy Bottoms a sustainable healthy wetland. Background information suggestedthat the various data points had to be within a specific range to be deemed healthy. Threedifferent locations at the wetland were picked, and each location was tested for dissolvedoxygen, pH, conductivity, and temperature four times in the course of five weeks. Theresults showed that both locations two and three met established standards for waterquality (“5.9 Conductivity”, “Dissolved Oxygen”, “Recommended pH action level”), butlocation one did not completely meet standards. However, it was adequate becauselocation one is the inflow location and one would expect it to have a lower water quality.Big IdeaWater quality is a system of rating the quality of a particular water source. It is especiallyimportant in the wild, where it impacts the surrounding environment.Background InformationThe wetlands of the San Juan valley go back a long time in their interaction with humans.At one point, it was possible to canoe from one end of the valley to the other. NativeS’Klallam tribal members did this to avoid Point Wilson’s treacherous waters. Aftersettlement, the San Juan valley was used primarily as farm land. Froggy Bottoms wasused for farmland, but then became a horse pasture. A seasonal pond would gather abouthalf way in between the present day Cedar and Tremont Streets, covering the Milo Streetright of way. Major filling had been done on the north end of the property. In 1997, theCity of Port Townsend acquired the property, partly for storm water and wastewaterpurposes. The property was not in very good shape. The previous owner, who was a cityemployee, had requested that the city dump old gravel to fill the north end. Dump trucksand bulldozers had roamed the site. The city installed a sewer line along the south side ofthe property. However, the one large reason for acquisition was storm water run off fromSan Juan Ave. The city redid San Juan Ave. at the time, imposing even a more pressingneed for storm water control. The San Juan valley is filled with many seasonal wetlands.The city categorized the various wetlands, naming Froggy Bottoms “Wetland 6-1”. Thecity hired a consulting firm to carry out a redesign of the wetland. The final result was aconventional wetland that dealt with storm water effectively. The north bank wasexcavated and dumped where the current pond was, shifting the pond north. The locationof the pond right now is on impermeable glacial till, so that the water table does not godown, but does have an outlet at a certain rate. It does dry up in the summer, however.Storm water from four storm sewer grates drains into a small settling pond beforeentering the wetland. It was designed to keep sediment and other contaminants out of thewetland as much as possible. Native plants and shrubs were also planted at the wetland.
Some of the invasive species in the wetland before restoration included poison hemlock,himalayan blackberries, and orchard grass. Some new plants that were planted includenootka rose, curly dock, bluegrass, creeping buttercup, and tall fescue. This is the firstfield study done on Wetland 6-1 that is known.There are many benefits and functions of wetlands. Wetlands develop plant food andshellfish, along with regular fish for sustaining wildlife and economic development.Wetlands also provide a good recreational area for bird watchers and people who like tophotograph or watch nature. Wetlands are especially important because they controlwater quality. They can prevent pollution or sediment from going into streams or riversby letting it settle out. Wetlands are essential to wildlife. They provide habitat to manyspecies, like frogs, that can thrive in wetlands. Wetlands also help control floods bytaking some of the extra water from swollen creeks and rivers and diverting it into thebrackish wetland or backwater areas.A healthy wetland should have plants and animals using it, and should not have anysignificant pollution in it. However, here are some data ranges that may be helpful indetermining if Wetland 6-1 is a healthy wetland. The pH should be between 6 and 9,according to the Massachusetts Department of Environmental Protection. Dissolvedoxygen should range from about 4-11 mg/L, with 7-11 mg/L being very good for streamswith fish. Four-7 mg/L is ample enough for ponds. The United States EnvironmentalProtection Agency states that most healthy lakes in the United States have a conductivitylevel between 150 and 500.Research QuestionDoes Wetland 6-1 have similar ranges of pH, conductivity, and dissolved oxygen as thehealthy levels portrayed in the background information?Experimental DesignThere are three locations in this experiment. Location one was picked because it is theinflow of the water to the pond, plus it seemed like an area that would give interestingresults. Location two is close to location one, but in the main pond. It was a good area totest because it is in brackish water, which is probably the most susceptible part of awetland to contamination. Location three is across the pond from the other locations, andwas necessary to get an overall picture of the pond. See the Map for the exact locations.
The four things that were tested were temperature, conductivity, pH, and dissolvedoxygen. Dissolved oxygen, conductivity, and pH probes need to be rinsed with distilledwater before and after use. It is also necessary to calibrate the dissolved oxygen probe onsite. Use film containers to hold about 100 ml of distilled water. That way, each probewill have a before and after container that can be used. First take the temperature probe,the conductivity probe, and the pH probe and put them in a plastic tub. Also put in thetub a rag and the necessary film containers with distilled water. Have a Vernier LabQ orsimilar interface unit with you at all times. With these materials, go to all the locations inorder. Record the start time using the clock on the interface unit. First, take thetemperature, and then record it. While measuring data with any of these probes, oneshould make sure not to record the data until the reading stabilizes. Then, take theconductivity probe and rinse it in distilled water. Then record the conductivity. Put theconductivity meter on the setting of 0-200, because pond water has low conductivitycompared to some waters. After one takes the conductivity measurement, rinse the probein distilled water, and then wipe it dry with a clean rag. For the pH sensor, unscrew thebottle with pH base four solution in it, and then take the probe out of the bottle, leavingthe lid attached. Then remove the lid from the probe. Rinse the pH sensor in distilledwater. Measure the pH and record it. Then rinse the sensor in distilled water, andcarefully wipe it with the rag. Place it back in the bottle with the pH base four.
However, only screw on the lid about half way. Then place the probe into the bottle andpush it in so that it is fully immersed in the base four solution. Fully screw on the lid.Then repeat all the testing steps, from the recording of the time to screwing on the lid ofthe pH sensor at locations two and three as well. After that, one needs to calibrate thedissolved oxygen probe. In order to do this, follow the directions on the instruction sheetthat came with the probe. First, add 1 ml of DO-electrode filling solution that comes withthe probe. Warm up the dissolved oxygen probe for ten minutes in one of the filmcontainers of water, while connected to the interface. While waiting, take the airtemperature by plugging the temperature sensor into another port. Then enter thecalibration program on the interface, which is accessed through the menus at the top.Click on calibrate, and then “Calibrate DO Probe”. Then place the DO probe in theSodium Sulfate solution that came with the probe for about 10 seconds. Enter 0 as thefirst value in the calibration routine. Then squeeze the bottle of Sodium Sulfate solutionso that there is no air inside. The solution will keep longer this way. Then rinse theprobe in distilled water and place it in the provided calibration bottle, and slide the lidabout ½ inch onto the probe body. Add about ¼ inch of water to the bottom of the bottleand screw on the cap. When the reading stabilizes, enter the correct value based on theair temperature and the barometric pressure. Then go around to all the testing sites,measuring, and recording the data. Carry the probe around in one of the film containersof distilled water, but blot the probe dry before and after running all of the tests. Makesure the probes are cleaned and stored correctly, and dump out all contaminated distilledwater.Materials Six film containers Access to distilled water One conductivity probe One dissolved oxygen probe One temperature probe One pH probe One Vernier LabQ or LabQuest 2 interface type model (or similar product) Instructions and extra supplies that come with the various probes Two rags One plastic tub Rubber boots
DataMarch 31, 2012Weather: Partly Cloudy with a chance of showers, High 8°C, low 3°C. 0.2” of rain in thelast 24 hours.Location Time H2O pH Conductivity Dissolved Temperature Oxygen1 3:12PM 7.6°C 5.9 49 μS/cm 8.3 mg/L2 3:40PM 8.6°C 6.8 267 μS/cm 8.6 mg/L3 4:00PM 9.0°C 6.7 277 μS/cm 5.0 mg/LApril 14, 2012Weather: No Rain in the last 24 hours, Current air temperature 9.9°C. Predicted: 11°C,sunny with scattered high clouds, calm wind.Location Time H2O pH Conductivity Dissolved Temperature Oxygen1 10:21AM 8.7°C 6.12 90 μS/cm 4.0 mg/L2 10:30AM 11.7°C 6.76 271.6 μS/cm 6.2 mg/L3 10:43AM 10.8°C 6.90 279.6 μS/cm 4.0 mg/LApril 21, 2012Weather: Sunny with a high of 13°C, clear. 0.4” of rain in the last 24 hours.Observations: Water level has risen to about where it was on March 31. Algae coversabout half the pond.Location Time H2O pH Conductivity Dissolved Temperature Oxygen1 11:29AM 11.0°C 5.62 41.5 μS/cm 8.7 mg/L2 11:37AM 17.3°C 6.95 267.5 μS/cm 9.4 mg/L3 11:46AM 14.4°C 6.91 278.1 μS/cm 4.6 mg/LMay 5, 2012Weather: High of 12°C, low of 6°C. Mostly cloudy, 0.5” of rain in the last 24 hours.Observations: Water level is the highest I have seen while I have been testing. There ismore algae than on April 21. The only places that do not have any algae are by locationthree and in the middle of the pond.Location Time H2O pH Conductivity Dissolved Temperature Oxygen1 10:48AM 11.1°C 5.62 52.6 μS/cm 6.5 mg/L2 10:56AM 13.9°C 6.77 188.7 μS/cm 8.5 mg/L3 11:08AM 13.1°C 6.89 279.4 μS/cm 5.1 mg/L
Conductivity Graph (μS/cm) 300 250 200 Location 1 150 Location 2 100 Location 3 50 0 31- 14- 21- 5- Mar Apr Apr MayDissolved Oxygen Graph (mg/L) 10 8 Location 1 6 Location 2 4 Location 3 2 0 31- 14- 21- 5-May Mar Apr AprRainfall Graph 2.5 2 1.5 Rainfall 1 (inches) 0.5 0 04 5-0 24 04 1-0 31 04 8-0 07 04 5-0 14 04 2-0 21 9- 28 5 /0 /2 3/ /0 3/ /0 4/ /1 4/ /2 4/ /2 4/ 05 03 8-0 /1 03As one might expect, temperature increased steadily during the study. The pH was alsopretty constant during the study. The conductivity leveled off or decreased. Dissolvedoxygen decreased initially, but then went up again. Dissolved oxygen and temperaturedo seem have a correlation, but I also think that dissolved oxygen and rainfall seem tohave a more direct relationship.
ConclusionsFroggy Bottoms has the characteristics of a healthy functioning wetland. Based on thebackground information, most of the data meets the requirements of a healthy wetland.For pH, all of the data values, except location one, are above six, which meets the criteriastated in the background information. Location one’s unusual data stems from the factthat location one drains San Juan Ave., so it would be more susceptible to contamination,and therefore acidity. The conductivity levels also are acceptable, as applied to thebackground information. However, again location one has levels that do not meet theconductivity standards of the US EPA. This is probably because there is a noticeableinflow from the storm sewer into the location one area, and because the water is moving,there is less time for solids to sink. Dissolved oxygen of the wetland meets the standardsof 4-11 mg/L. Locations three and one had the lowest dissolved oxygen at 4.0 mg/L.However, locations two and one both had dissolved oxygen values above 7 mg/L, whichis considered enough to support fish in a small stream. Therefore, locations two andthree are good functioning wetland areas in terms of water quality. They both have datathat suggests that those parts of the wetland are healthy. Location one is a little different.Location one does not have enough dissolved solids in it to be deemed healthy by thestandards. In addition, the pH only rose over six once during my study. However,because location one is the settling pond for this wetland, it is expected that the data isnot going to be as high as in other sections of the wetland. Because of this, wetland 6-1isa healthy, functioning wetland.LimitationsThere are quite a few things that could be limitations in this experiment. The largest oneis that data was only taken for about two months in the year. Also, testing was notperformed everyday. Another limitation is that pH, temperature, conductivity, anddissolved oxygen were the only tests run.Next Focus Research QuestionDoes Wetland 6-1 contain fecal coliform?
Works CitedGibboney, Sam. “Re: Froggy Bottoms Questions.” Message to Ewan Shortess. 2 May 2012. E-mail.“Recommended pH Action Level.” Massachusetts Department of Environmental Protection. Government of Massachusetts, n.d. Web. 22 May 2012. <http://www.mass.gov/dep/water/laws/phral.htm>.“5.9 Conductivity.” United States Environmental Protection Agency. The United States Government, 6 Mar. 2012. Web. 22 May 2012. <http://water.epa.gov/type/rsl/monitoring/vms59.cfm>“Dissolved Oxygen.” Ecostudies.org. Cary Institute of Ecosystem Studies, n.d. Web. 22 May 2012. <http://www.ecostudies.org/chp/Module1/1C1_dissolved_oxygen_reading.pdf>“Economic Benefits of Wetlands.” United States Environmental Protection Agency. The United States Government, 12 Jan. 2009. Web. 22 May 2012. <http://www.epa.gov/owow/wetlands/facts/fact4.html>