2020 Taylor Pond Water Quality Report

Posted on October 23, 2020 by danawl

by Woody Trask

This report summarizes the findings of the 2020 water quality monitoring program for Taylor Pond in Auburn, Maine (MIDAS ID#3750). Clarity readings and samplings were conducted monthly from June through September by Woody Trask with additional clarity readings taken May through September by Michael Heskanen.

Since 2004, Taylor Pond Association has been collecting its own water samples and performing most tests. Phosphorus analyses are conducted by the DHHS Health and Environmental Testing Laboratory.

Result summary: Results were quite consistent with readings obtained for the past several years with one notable exception. A new maximum clarity reading of 7.0 meters obtained on May 30 exceeded the previous high by 0.75 meters (about 2.5 feet). The average clarity was slightly higher than last year mostly likely due to a dry summer with less runoff going into the pond.

Water coloration was the same as last year and close to the historic average.

Readings for pH and alkalinity were unchanged from past years. Conductivity was slightly higher.

The average surface temperature taken at 1 meter depth was 23.3°C (73.9°F), 0.3°C (0.5°F) lower than last year and 0.4°C (0.72°F) higher than the average for the past 10 years.

“Ice in” occurred on the 4^th of December 2019 (1 day earlier than 2018) and the “ice out” date was April 2nd (3 weeks earlier than 2019). The historical average for ice out is April 14.

The results of this year’s monitoring are given below and in a separate DO/Temperature report.

*Parameter*	*2020*	*Mean for Taylor Pond* *since 1975*	*Historical Mean for all Maine Lakes*
Color	21.25	21.04	28
pH	7.1	7.01	6.82
Alkalinity	20	17.1	11.9
Conductance, µS/cm	105	91.2	46
Total Phosphorous 5m core sample, µg/L	11.0vs. 10.25 in 2019	10.21	12
Total Phosphorousbottom grab, µg/L	17.5vs. 15.25 in 2019	24.58	(not published)
Secchi depth (meters) minimum	4.2vs. 3.8 in 2019	1.7 (minimum ever recorded)	0.5(0.9 in 2012)
Secchi depth mean (m)	5.35vs. 5.0 in 2019	4.70	4.81(5.2 in 2012)
Secchi depth max (m)	7.0vs. 6.2 in 2019	7.0 (a new record high)	15.5 (13.4 in 2012)
Trophic State (by Secchi disk)	35.8	49.20	45
Trophic State (by core Total Phosphorus)	38.7	42.75	(not published)

Color:

Organic material that remains from dead plants and animals provides most of the water color. Lakes drained by areas with more coniferous forests tend to be brown in color due to the slow degradation of the leaves of these trees. Taylor Pond had a color measured at 21.25 in 2020, which is slightly higher than last year and lower than the mean for all Maine lakes of 28. When the color is greater than 25 a lake is considered “colored” and the transparency is reduced.

PH:

A measure of the acid-base status of the pond. Taylor Pond had a pH of 7.1 in 2020 which is slightly higher than the mean of 6.82 for all Maine Lakes. Acid rain caused by industrial pollutants can cause the pH in lakes to drop below 6. This drop in pH kills off the healthy zooplankton (microscopic animals) leading to death of fish and overgrowth of algae. The pH of Taylor Pond has been very stable over the years.

Alkalinity:

A measure of the capacity of the water to buffer against a change in the pH. Taylor Pond’s alkalinity in 2020 was 20 (the same as last year) compared to a mean for all Maine lakes of 11.9. This indicates that our pond is unlikely to have a problem with acidity. The level of alkalinity in Taylor Pond has remained constant and is not of concern.

Conductance:

Conductance indirectly measures the relative number of dissolved ions in the water — the higher the concentration of ions the greater the conductance. Conductance is used as a rough estimate of the amount of pollutants which usually are present as ions. Although conductance is easy to measure it is not considered highly reliable. Taylor Pond’s conductance for 2020 was 105 compared to a historical mean of 91.2 and a mean of 46 for all Maine lakes.

Total Phosphorous:

A phosphorus analysis provides the most reliable measure of the capacity of Taylor Pond to have an algal bloom. Algae in Maine waters tend to be limited by the phosphorous content of the water. If you provide enough phosphorous algae grows rapidly. Algae cause depletion of oxygen in the water which kills animal life, colors the water green and when it dies creates unpleasant odors. Taylor Pond’s phosphorous was done using a 5 meter core and bottom grab sampling technique. Taylor Pond’s core sample phosphorous readings this year averaged 11.0 µg/L which is comparable to the historical mean of 10.21 and lower than the 12 reported for all Maine lakes. In 2020 there were no 5 meter core results close to the 15 µg/L level that can initiate algal blooms. Lakes are categorized as oligotrophic (low level of biologic productivity), mesotrophic (intermediate) or eutrophic (high biologic productivity) based on how much phosphorous they contain. A lake with a phosphorous of less than 10 is considered oligotrophic, between 10 and 30 is considered mesotrophic and over 30 is considered eutrophic.

The bottom grab sample average of 17.5 µg/L was higher than last year’s average and lower than the historical average.

Secchi Disk:

Secchi disk readings provide the easiest method for measuring the clarity of the water. Algae, zooplankton (microscopic animals), natural water color and suspended soil all reduce the transparency of the water. Algae cause most of the change in transparency in Taylor Pond, but pine pollen at times is also a major contributor. The mean transparency for 2020 was 5.35 meters, 3.5 m. higher than last year due primarily to a highest reading ever of 7.0 meters taken at the end of May. The mean for 2020 was higher than the historic average for Taylor Pond of 4.70 and higher than the historical average for all Maine lakes.

Trophic State:

This is a measure of the biologic productivity of the pond — the higher the number, the more biologically productive the lake and typically the poorer the water quality. The scale ranges from zero to over 100. Ponds in the range between 40 and 50 are considered mesotrophic (moderately productive). Values greater than 50 are associated with eutrophy (high productivity) and values less than 40 are associated with oligotrophy (low productivity). Taylor Pond measured at 35.8 by Secchi Disk readings and 38.7 by phosphorous readings (considered the most accurate). Taylor Pond’s Trophic State as measured by the Secchi disk is lower than the state average of 45.

Dissolved Oxygen and Temperature Profiles:

The amount of dissolved oxygen is measured at the surface and at one meter depth intervals monthly throughout the summer. Generally down to a depth of 5 meters the oxygen level remains at a high enough level to sustain all animals. Below 5 meters the oxygen levels early in the summer are high, but as the summer progresses the oxygen levels drop to levels (below 5 ppm) unable to sustain fish and other aquatic animals. Warm water fish (such as Sunfish, Perch, Pickerel and Bass) have no difficulty in Taylor Pond because they stay near the surface where the water is well oxygenated. Cold water fish (such as Trout and Salmon) need the deeper colder water, below 20 degrees Celsius, to thrive. By July or August, this colder, deeper water no longer contains enough oxygen for fish. In addition to the difficulty for fish, oxygen depletion near the bottom of the pond tends to release phosphorous into the water. This is demonstrated by the higher phosphorous levels found in the bottom grab samples by the middle of the summer. The oxygen depletion found below 4-8 meters is similar to what we have found in the past and continues to reflect the fragile state of Taylor Pond. The DO and Temperature profiles for 2020 are on a separate chart (attached).

Conclusions:

The conclusions remain essentially unchanged from last year. The water quality of Taylor Pond is considered to be average compared to other Maine lakes. The potential for an algal bloom continues to be low to moderate, with the average Phosphorus of 11.0 µg/L for 2020 being in line with the historical average. Taylor Pond remains one of the 181 Maine lakes on the Maine Department of Environmental Protections Nonpoint Source Priority Watershed list. This list contains those lakes considered to be threatened or impaired by nonpoint source pollution from land use activities on the surrounding watershed. In addition the Stormwater Management Law considers Taylor Pond to be a lake “most at risk”.

Taylor Pond fails to meet standards for the highest water quality due to the depletion of oxygen found at depths below 5 meters during the summer (see DO/Temp chart). In addition, phosphorous levels remain just below the threshold of 15 which could trigger an algal bloom. Monitoring of Taylor Pond has been conducted regularly since 1975. During this time there has been no consistent trend in the parameters measured. Since 2004, the years Taylor Pond has been monitored by volunteers, there have been no appreciable algae blooms.

Because of the shallow depth of the pond (mean depth 17 feet) and low flushing rate (1.34 flushes per year, the number of times the water, on average, empties from the pond) Taylor Pond will likely always remain vulnerable to phosphorous loading and therefore algal blooms. Because of oxygen depletion of deep water during the summer, the pond will likely never sustain a cold water fishery. Finally, each new structure or expansion of an existing structure, whether a home, garage, driveway, road, lawn or beach, potentially increases the phosphorous loading of the pond.

Taylor Pond continues to have many attractive qualities. The shallow depth means that it quickly warms in the summer to provide excellent swimming close to the towns of Auburn and Lewiston. It freezes quickly in the winter to provide skating, skiing and ice fishing during the winter. It has an abundant bass, pickerel, and recently pike populations that thrive in its warm waters and attract people who enjoy fishing. The Department of Marine Resources considers the pond to be prime spawning habitat for alewives and trucks adult fish above the dams on the Androscoggin River into Taylor Pond. It has a naturally high level of biologic productivity that sustains an abundant wildlife population for all to enjoy. It remains a place that never ceases to astound us with its beauty.

METHODOLOGY:

Samples are collected at the deepest point in the pond. This point has been determined previously and the historic location has been noted on maps available to the samplers along with GPS coordinates. This spot is reached by boat and verified each time by visual triangulation or GPS reading. In addition to visual triangulation an ultrasound depth meter is used before collecting core and grab samples. Grab samples are taken using a Van Dorn Water Sampler. Core samples are taken with a core sampler home-manufactured from a 50 foot flexible PVC tube. The method for grab samples at a specified depth and core samples are done according to the protocol of the Maine Bureau of Land and Water Quality, Division of Environmental Assessment.

COLOR: Performed on core samples using a Hach color wheel (CO 20-100) and units are in Standard Platinum Units (SPU).

PH: Performed on core samples using a Hach Bromothymol Blue test kit for pH.

CONDUCTANCE: Performed on core samples using a HM Digital, Inc. Model COM-100 water quality tester for EC/TDS/Temp. Conductivity is measured in uS/cm.

ALKALINITY: Performed on core samples using a titration method with a Hach color wheel measured in milligram per liter.

PHOSPHOROUS: Performed on core samples and bottom grab samples. Samples are collected in the field, refrigerated and sent to the DHHS lab by mail. Measurements are in parts per billion (ppb). The results are the average of four samples taken once a month from June to September.

SECCHI DISK: Performed using the method taught by the Maine Volunteer Lake Monitoring Program. Only certified users performed this task. Measurements of depth are in meters.

DISSOLVED OXYGEN: Performed in the field using a YSI 550A DO meter with 50 foot probe which measures temperature and dissolved oxygen from the surface to maximum depth. The sampler and meter is yearly certified by the Maine Volunteer Lake Monitoring Program as to method and accuracy. Measurements of dissolved oxygen are in milligrams per liter (mg/l). Water temperature is recorded at each depth tested.

TROPHIC STATE: Carlson’s Trophic State Index (TSI) is used in these calculations. For Secchi disk depth TSI = 60 – 14.41 x (Natural Log of Secchi disk depth in meters). For total phosphorus TSI = 14.42 x (Natural Log of total phosphorous) + 4.15.

Taylor Pond DO-TEMP Reading 2020 Download

Phosphorus results 2009 – 2020 Download

Woody Trask

10/23/2020

Sunrise mist

Posted on August 31, 2020 by danawl

The water measured 70 degrees Fahrenheit and the air 46 this morning creating mist rising from the surface. It looked to me like the sun was boiling the water.

August Pond Flowers

Posted on August 27, 2020 by danawl

Native Swamp Loosestrife growing along the edge of Taylor Pond hang over the water.

Close-up of the bright lavender flowers of loosestrife.

Broad-leaved Arrowhead. Note the floating arrow-shaped leaves and three-petaled flowers.

Fragrant Water-Lilly, late in the season but still spectacular. The lower leaf is patterned with insect burrows.

Buttonbush, aptly named for its unique flowers, colonizes the wetland swamps around the pond and attracts hordes of bees.

Pickerelweed with purple flowers live in shallow water, an emergent Fragrant Water-lily in the foreground.

Spotted Touch-me-not thrives in shaded wetlands.

Bullhead-lily with large floating leaves and an emergent yellow flower lives in shallow water all around the pond.

Sunrise Photos

Posted on August 23, 2020 by danawl

by Wylie Mitchell

TAYLOR POND VALUATION UPDATE

Posted on August 23, 2020 by danawl

by Barbara Mitchell

The City of Auburn, Assessing Division has been engaged in a review of waterfront Taylor Pond property values. This multi-year appraisal process includes an analysis of sales and property inspections. As of April 1, 2020 the analysis was not complete. As such there will be no market adjustments made for the upcoming tax year as a direct result of the study.

Although there will not be any overall market adjustments for the upcoming tax year, edits to value were necessary for some properties following inspections. These adjustments were for new additions, demolitions, decks, garages, miscellaneous outbuildings, additional bathrooms, condition changes or other corrections that were discovered during the inspections or subsequent to permit work.

The Taylor Pond study includes 196 total parcels. Only 28% of properties saw a value increase. For the most part, any adjustments were minor – often they were less than 1% of the improvement value. Value reductions were posted for 29% of properties and 43% of properties saw no change in value. The Assessing Division intends to notify all Taylor Pond property owners whether or not their value changed in a letter prior to commitment, although the COVID-19 outbreak hampered efforts to do this. They hope to notify individual property owners before July 1, 2020.

Homeowners should also be aware that the homestead exemption is being raised from $20,000 to $25,000 this year. This means that many Taylor Pond year round property owners (who have a homestead exemption) will likely see their taxes decrease, even if the property value increases – because very few increased more than $5,000.

Property Value	Number of Properties
REDUCED	57
NO CHANGE	84
INCREASED*	55

*These increases were overwhelmingly minor, from 0.02% to 14.17%. Only three properties had an improvement value increase greater than 10%.

Source: www.auburnmaine.gov

PRESIDENT’S REPORT

Posted on August 23, 2020 by danawl

by Dana Little

Taylor Pond Association (TPA) is dedicated to protecting the quality of water in and life on the pond. Thanks to the vigilance and partnership of property owners, we continue to report that both are very good! As a community and as stewards of this valuable natural resource, we can take pride in our collective work…and then redouble our efforts to do even better next year. Your individual work–avoiding pesticides and fertilizer, preventing runoff, being responsible boaters, and respecting wildlife habitat–is ongoing and critical to pond health.

WATER QUALITY

Central to our mission is monitoring the quality of water in Taylor Pond. Woody Trask manages testing and provides the annual water quality report, where we are reminded that invasive aquatic plants represent the most imminent danger to our enjoyment of the pond. A pond filled with invasive plants can make swimming and boating unpleasant, even impossible. Last year Michael Heskanen and I toured the entire lake looking for these aliens, and are happy to report that none were found from the surface. This summer, we are looking for volunteer swimmers and divers to expand this surveillance underwater. And as always, it is critical for boaters to thoroughly inspect their boats before launching.

PROPERTY VALUES & POND HEALTH

We work with local and state officials responding to inquiries, and advocate for the health of our pond. Read Barbara Mitchell’s update on Auburn’s reevaluation of Taylor Pond properties and the status of planned improvements to the Hotel Road Taylor Brook culvert for flood mitigation. Please consider taking advantage of the LakeSmart program –a free evaluation of your property, suggestions for improvements that will keep the pond healthy and a possible $500 matching grant to make those improvements.

BECOME A VOLUNTEER

Please consider volunteering with Taylor Pond Association, which depends on the time and talents of many. There are many ways to serve, including attending public meetings, water quality monitoring, advocacy, education or Board membership. TPA maintains a website www.taylorpond.org where you can read more about the organization and its activities. Learn more about lake stewardship in general, and how you can be involved, online at either the Lake Stewards of Maine (www.mainevlmp.org) or the Maine Lakes Society (mainelakessociety.org). Both are holding their annual conferences virtually this year, providing these excellent education opportunities to a broader audience (see page 11).

ANNUAL MEETING & COVID-19

Our Annual Meeting is scheduled for August 23 at Taylor Pond Yacht Club, pending COVID-19 developments and our ability to offer a safe meeting format. We will keep you updated via email. As noted on the invoice sent in May, dues are optional this year in response to the economic hardship of the pandemic and therefore a reminder invoice is not enclosed in this newsletter. Your support of our mission, however you are able to show it, is always highly valued. Thank you.

MIDGES & MAYFLIES

Posted on August 23, 2020 by danawl

by Dana Little

What are those swarms of insects found hovering in the air near the pond? Midges make up most of these groups. The small flies look like tiny mosquitoes but do not bite. They smear our windshield on a summer night’s drive, swarm over our head as we walk near the pond, cluster near bushes and collect around our porch lights at night. Most of their life they live in the water and only emerge as adult flies when the water warms up. Midges first appeared this year in early May, signaling that mayflies would soon appear.

Mayflies emerge as the pond water warms further. The first hatch I observed this year occurred in mid-May. Although called mayflies, adults appear all summer long, each species emerging at different times. It has been claimed that there are 162 species that live in Maine. When perched they hold their wings over their back like two praying hands. The adult female lays eggs in the water. The eggs hatch into the larval stage, the nymph. To mature, the nymph lives in water for up to three years. When signaled by rising water temperature, thousands of nymphs come to the water’s surface where their skin splits and the adults emerge, ready to form a swarm.

Recently emerged Mayfly (2 inches long), resting on an Alder Leaf

Swarms of midges and mayflies can be so large that weather radar will pick them up. Estimates of swarm sizes range up to 80 billion individuals. In past springs along Lake Erie, snow plows were used to scoop them off the roads. As reported in National Geographic recently, scientists have found that the numbers of mayflies around Lake Erie have declined by 50%. The cause is thought to be water pollution which kills the nymphs.

Males predominate in swarms, whether midges or mayflies. They cluster together, flying rapidly up and down, waiting for females. Once they mate the female immediately flies to the water and lays her eggs to begin the cycle again. Mayflies belong to the group of insects called Ephemeroptera, the name of which is derived from the Greek words ephemeros (lasting only a day) and ptera (wings). Whereas the aquatic nymph stage lasts up to three years, the flying adult may live only a few hours or days.

Both mayflies and midges provide food for wildlife. Midges eat algae and decaying plants in the water and thereby remove phosphorus, improving the health of the pond. Abundant mayflies in a pond are also a sign of good water quality. Like midges, they remove phosphorus from the pond, and do not bite. So please welcome the annual emergence of midges and mayflies.

SHORELINE IMPROVEMENT GRANTS SUPPORT TAYLOR POND WATER QUALITY

Posted on August 23, 2020 by danawl

It’s Summer…finally! Whether your idea of summer on Taylor Pond includes boating, floating, paddling, fishing, sailing, or simply relaxing in a deck chair on solid ground, you count on its clean water and accessible shoreline to get the most out of every, precious summer day. We all do. Of all the issues on TPA agendas over the years, none is more consistent and more important than water quality. It is no accident that our water is clear; it’s thanks to the stewardship of us all.

One of the best ways to maintain water quality is from the shore. TPA offers help to property owners who want to make their shoreline more lake friendly. Free property evaluations and matching grants up to $500 are available to members. Participation is completely voluntary. Property owners can opt out at any time (i.e. they are not required to implement any improvement suggestions and the property evaluation is purely educational, not regulatory).

Evaluations do advise property owners on Maine’s shoreland zoning law and include customized recommendations for property improvements that will keep the pond healthy such as:

Preventing rain runoff from directly entering the pond
Planting a buffer along the shore
Leaving grass at least three inches long when cutting
Avoiding pesticides and fertilizers and
Reducing lawn sizes

Homeowners (or road associations) who do want to apply for a matching grant (up to $500) will follow these steps:

An initial, free LakeSmart property evaluation
Make improvements as recommended in the written evaluation
Provide proof of associated costs
Not make changes to the property that would worsen its score
Have a follow up evaluation to ensure satisfactory work

To find out more or schedule a LakeSmart evaluation, call Kristi Norcross at 577-6408.

FLOODING: TAYLOR BROOK BRIDGE

Posted on August 23, 2020 by danawl

In 2017, TPA commissioned an engineering study of water levels and flooding issues on Taylor Pond. The study concluded that removing obstructions to the free flow of Taylor Brook under Hotel Road and Stevens Mill Extension could reduce the chance of flooding on the pond. In 2019 Maine Department of Transportation (DOT) made plans to improve the Hotel Road culvert, but the project has been delayed (more than once) due to escalation of project costs. The project is currently in the DOT work plan for construction in 2021, an unfortunate delay.
The good news is, once done it will reduce the chance of flooding. Instead of a limited culvert, this will be a bridge that allows water to pass freely down and fish to swim upriver. Research shows this is better environmentally and cost wise. It is more expensive to construct initially, but requires less maintenance and should have a much longer lifespan than a culvert.

Flooded home on Taylor Pond after hurricane Sandy.

2019 Water Quality Report

Posted on December 27, 2019 by danawl

By Woody Trask

This report summarizes the findings of the 2019 water quality monitoring program for Taylor Pond in Auburn, Maine (MIDAS ID#3750). Clarity readings and samplings were conducted monthly from June through September by Woody Trask with additional clarity readings taken May through September by Michael Heskanen.

Since 2004, Taylor Pond Association has been collecting its own water samples and performing most tests. Phosphorus analyses are conducted by the DHHS Health and Environmental Testing Laboratory in Augusta.

Result summary: Results were quite consistent with readings obtained for the past several years, with no result raising a potential concern.

The average 5 meter core sample phosphorus reading was up slightly from last year but was consistent with the historical average. The bottom (12 meter) phosphorus reading by contrast was much lower than last year and was well below the historical average. The average clarity of 5.0 meters was slightly less than last year. Water coloration was the same as last year and close to the historic average. Readings for pH and alkalinity were unchanged from past years. Conductivity was slightly higher. The average surface temperature was 23.6°C (74.5°F), 0.33°C (0.6°F) higher than last year and also 0.33°C higher than the average for the past six years. “Ice in” occurred on the 5^th of December 2018 (10 days earlier than 2017) and the “ice out” date was April 23rd (one day earlier than 2018). The historical average for ice out is April 14. The results of this year’s monitoring are given below and in a separate DO/Temperature report.

*Parameter*	*2019*	*Mean for Taylor Pond* *since 1975*	*Historical Mean for all Maine Lakes*
Color	20	21.04	28
pH	7.1	7.01	6.82
Alkalinity	20	17.0	11.9
Conductance, µS/cm	109	90.6	46
Total Phosphorous 5m core sample, µg/L	10.25vs. 9.5 in 2018	10.17	12
Total Phosphorousbottom grab, µg/L	15.25vs. 21.25 in 2018	24.91	(not published)
Secchi depth (meters) minimum	3.8 (on 9/18)vs. 4.8 in 2018	1.7 (minimum ever recorded)	0.5(0.9 in 2012)
Secchi depth mean (m)	5.0vs. 5.3 in 2018	4.68	4.81(5.2 in 2012)
Secchi depth max (m)	6.2 (on 6/9)vs. 6.5 in 2018	6.52 (maximum ever recorded)	15.5 (13.4 in 2012)
Trophic State (by Secchi disk)	36.8	49.50	45
Trophic State (by core Total Phosphorous)	37.7	42.84	(not published)

Color: Organic material that remains from dead plants and animals provides most of the water color. Lakes drained by areas with more coniferous forests tend to be brown in color due to the slow degradation of the leaves of these trees. Taylor Pond had a color measured at 20 in 2019, which is slightly higher than last year and lower than the mean for all Maine lakes of 28. When the color is greater than 25 a lake is considered “colored” and the transparency is reduced.

PH: A measure of the acid-base status of the pond. Taylor Pond had a pH of 7.1 in 2019 which is slightly higher than the mean of 6.82 for all Maine Lakes. Acid rain caused by industrial pollutants can cause the pH in lakes to drop below 6. This drop in pH kills off the healthy zooplankton (microscopic animals) leading to death of fish and overgrowth of algae. The pH of Taylor Pond has been very stable over the years.

Alkalinity: A measure of the capacity of the water to buffer against a change in the pH. Taylor Pond’s alkalinity in 2019 was 20 (the same as last year) compared to a mean for all Maine lakes of 11.9. This indicates that our pond is unlikely to have a problem with acidity. The level of alkalinity in Taylor Pond has remained constant and is not of concern.

Conductance: Conductance indirectly measures the relative number of dissolved ions in the water — the higher the concentration of ions the greater the conductance. Conductance is used as a rough estimate of the amount of pollutants which usually are present as ions. Although conductance is easy to measure it is not considered highly reliable. Taylor Pond’s conductance for 2019 was 109 compared to a historical mean of 90.6 and a mean of 46 for all Maine lakes.

Total Phosphorous: A phosphorus analysis provides the most reliable measure of the capacity of Taylor Pond to have an algal bloom. Algae in Maine waters tend to be limited by the phosphorous content of the water. If you provide enough phosphorous algae grows rapidly. Algae cause depletion of oxygen in the water which kills animal life, colors the water green and when it dies creates unpleasant odors. Taylor Pond’s phosphorous was done using a 5 meter core and bottom grab sampling technique. Taylor Pond’s core sample phosphorous readings this year averaged 10.25 µg/L which is comparable to the historical mean of 10.17 and lower than the 12 reported for all Maine lakes. In 2019 there were no 5 meter core results close to the 15 µg/L level that can initiate algal blooms. Lakes are categorized as oligotrophic (low level of biologic productivity), mesotrophic (intermediate) or eutrophic (high biologic productivity) based on how much phosphorous they contain. A lake with a phosphorous of less than 10 is considered oligotrophic, between 10 and 30 is considered mesotrophic and over 30 is considered eutrophic. The bottom grab sample average of 15.25 µg/L was lower than last year’s average and lower than the historical average.

Secchi Disk: Secchi disk readings provide the easiest method for measuring the clarity of the water. Algae, zooplankton (microscopic animals), natural water color and suspended soil all reduce the transparency of the water. Algae cause most of the change in transparency in Taylor Pond, but pine pollen at times is also a major contributor. The mean transparency for 2019 was 5.0 meters, slightly less than last year due to some low readings in September but higher than the historic average for Taylor Pond of 4.68 and higher than the historical average for all Maine lakes.

Trophic State: This is a measure of the biologic productivity of the pond — the higher the number, the more biologically productive the lake and typically the poorer the water quality. The scale ranges from zero to over 100. Ponds in the range between 40 and 50 are considered mesotrophic (moderately productive). Values greater than 50 are associated with eutrophy (high productivity) and values less than 40 are associated with oligotrophy (low productivity). Taylor Pond measured at 36.8 by Secchi Disk readings and 37.7 by phosphorous readings (considered the most accurate). Taylor Pond’s Trophic State as measured by the Secchi disk is lower than the state average of 45.

Dissolved Oxygen and Temperature Profiles: The amount of dissolved oxygen is measured at the surface and at one meter depth intervals monthly throughout the summer. Generally down to a depth of 5 meters the oxygen level remains at a high enough level to sustain all animals. Below 5 meters the oxygen levels early in the summer are high, but as the summer progresses the oxygen levels drop to levels (below 5 ppm) unable to sustain fish and other aquatic animals. Warm water fish (such as Sunfish, Perch, Pickerel and Bass) have no difficulty in Taylor Pond because they stay near the surface where the water is well oxygenated. Cold water fish (such as Trout and Salmon) need the deeper colder water, below 20 degrees Celsius, to thrive. By July or August, this colder, deeper water no longer contains enough oxygen for fish. In addition to the difficulty for fish, oxygen depletion near the bottom of the pond tends to release phosphorous into the water. This is demonstrated by the higher phosphorous levels found in the bottom grab samples by the middle of the summer. The oxygen depletion found below 4-8 meters is similar to what we have found in the past and continues to reflect the fragile state of Taylor Pond. The DO and Temperature profiles for 2019 are on a separate chart (attached).

Conclusions: The conclusions remain essentially unchanged from last year. The water quality of Taylor Pond is considered to be average compared to other Maine lakes. The potential for an algal bloom continues to be low to moderate, with the average Phosphorus of 10.25 µg/L for 2019 being in line with the historical average. Taylor Pond remains one of the 181 Maine lakes on the Maine Department of Environmental Protections Nonpoint Source Priority Watershed list. This list contains those lakes considered to be threatened or impaired by nonpoint source pollution from land use activities on the surrounding watershed. In addition the Stormwater Management Law considers Taylor Pond to be a lake “most at risk”.

METHODOLOGY: Samples are collected at the deepest point in the pond. This point has been determined previously and the historic location has been noted on maps available to the samplers along with GPS coordinates. This spot is reached by boat and verified each time by visual triangulation or GPS reading. In addition to visual triangulation an ultrasound depth meter is used before collecting core and grab samples. Grab samples are taken using a Van Dorn Water Sampler. Core samples are taken with a core sampler home-manufactured from a 50 foot flexible PVC tube. The method for grab samples at a specified depth and core samples are done according to the protocol of the Maine Bureau of Land and Water Quality, Division of Environmental Assessment.

COLOR: Performed on core samples using a Hach color wheel (CO 20-100) and units are in Standard Platinum Units (SPU).

PH: Performed on core samples using a Hach Bromothymol Blue test kit for pH.

CONDUCTANCE: Performed on core samples using a HM Digital, Inc. Model COM-100 water quality tester for EC/TDS/Temp. Conductivity is measured in uS/cm.

ALKALINITY: Performed on core samples using a titration method with a Hach color wheel measured in milligram per liter.

PHOSPHOROUS: Performed on core samples and bottom grab samples. Samples are collected in the field, refrigerated and sent to the DHHS lab by mail. Measurements are in parts per billion (ppb). The results are the average of four samples taken once a month from June to September.

SECCHI DISK: Performed using the method taught by the Maine Volunteer Lake Monitoring Program. Only certified users performed this task. Measurements of depth are in meters.

DISSOLVED OXYGEN: Performed in the field using a YSI 550A DO meter with 50 foot probe which measures temperature and dissolved oxygen from the surface to maximum depth. The sampler and meter is yearly certified by the Maine Volunteer Lake Monitoring Program as to method and accuracy. Measurements of dissolved oxygen are in milligrams per liter (mg/l). Water temperature is recorded at each depth tested.

TROPHIC STATE: Carlson’s Trophic State Index (TSI) is used in these calculations. For Secchi disk depth TSI = 60 – 14.41 x (Natural Log of Secchi disk depth in meters). For total phosphorus TSI = 14.42 x (Natural Log of total phosphorous) + 4.15.