A Possible Answer to Alkaline Lake Water
We have been trying to make sense of the
alkaline water that showed up in our last
Watershed Water tests of Patterson Lake. We
have received some solid information and had
one “Ah ha”.
Ted Manning found on his cottage wall when he
bought the property a 1961 map from Lands &
Forest (L&F) Kemptville giving a depth profile
of the lake and species and location of timber
and aquatic plants, and fish species in the lake.
It was taped together in sections. Ted took
sectional photos of it, spent considerable time
splicing them together, and then sent us a copy.
Wow! As a small size it was so-so, but at 150%
enlargement the information will be a godsend
for our Lake Management Plan.
put the file up on our website in the LMP
section as 1961L&F.jpg.
I phoned Ministry of Natural Resources (MNR)
at Kemptville to see if I could buy or obtain a
better copy. In due course, a copy came of a
1969 L&F map of the lake which give the depth
profiles, but no distribution of aquatic or timber
species. But the notes that came with it were a
revelation. I will print it entirely below, but
here is the important part on alkalinity.
“The water is slightly alkaline with a pH of 8.3
at the surface. The water is clear with a Secchi
disc reading of 17.5 feet.”
In the testing done at a commercial water
testing lab by one of our lake neighbours this
summer, the results showed the water to have
a pH of 8.3 – which is an exact match of the
1969. It has not changed. It was slightly
alkaline in 1969 and it is slightly alkaline now.
(By the way, the Secchi reading of 17.5 feet is
the same as we have now so the clearness has
The notes that came along from the water
testing lab said that some southern Ontario
lakes were alkaline while some northern
Ontario lakes were acid.
Well OK. So why in the world would a lake in
the Canadian Shield be alkaline?
On the Thanksgiving Sunday, the multi-talented research staff of 151 Lakeside Rd had
an interesting discussion around the living
room about pH of our lake. One thing led to
another and Trevor Dee (our Son-in-Law) told
of finding a very bright green rock covered
with algae off Marys Island. He brought it
back (he is a rock hound and polisher). He
could not clear the junk off it so he took it
home and cut it in two. He looked at it and
thought it looked like marble, so he cut a few
pieces and put them in for tumbling in the
polisher. It turned out to be marble – white with
grey streaks. Marble is compressed limestone
and dissolved limestone is alkaline.
You will all have seen the rocks with holes in
them around the islands. If what were in those
holes was marble and it dissolved out over the
millennia, then that would give the alkalinity to
the lake. It is the best answer I have to date.
I Googled “marble rocks” and printed the
answer below. (Metamorphism in rocks is
defined as “a pronounced change effected by
pressure, heat, and water that results in a more
compact and more highly crystalline condition”
– Webster’s Dictionary).
What Type of Rock Is It? Metamorphic
What Does It Look Like? Often pure white. It
may be streaked or patchy grey, green, tan, or
red. Marble is fine grained to very coarse
grained and crystals are usually easy to see.
The rock is soft; it will not scratch glass
(quartzite may look like a fine grained marble,
but easily scratches glass). The powdered
marble will often fizz with white vinegar. If it
does not fizz, it may be dolomite marble.
What Minerals Make Up the Rock? calcite, or
dolomite (dolomitic marble); Sometimes:
graphite, pyrite, mica, tremolite, and a few
How Was It Formed? Marble forms from the
metamorphism of limestones.”
Just to finish this part off, I Googled “alkaline
water” and got all kinds of health related
products from China. That was interesting, but
what was more interesting was the widely used
definition of slightly alkaline to be a pH of less
that 9. Many of the products were around 9 or
Notes from 1969 L&F Map
Surface Area 368 acres
Volume 4.863 acre feet
Height above sea level 659 feet
Perimeter 7 miles
Maximum depth 62 feet
Mean Depth 13.3 feet
Origin of Name
The lake was known as Patterson Lake as early
as 1862. The earliest record of it as Patterson
Lake is 1904.
At the time of the survey this lake was
thermally stratified with a surface layer, about
10 feet deep at a temperature of 76°F. The
oxygen levels ranging from 10 to 7 parts per
million, were relatively high for a stratified
The water is slightly alkaline with a pH of 8.3
at the surface. The water is clear with a Secchi
disc reading of 17.5 feet.
The total dissolved solids reading is moderate
at 110 parts per million. This, together with a
high percentage of water being in the littoral
zone, and a large production of aquatic plants
indicates a reasonably productive lake.
Fish Species Present
Yellow pickerel, smallmouth bass, northern
pike, bluegill, yellow perch, rock bass,
pumpkinseeed, white sucker, golden shiner,
Angling success on Patterson Lake is fair for
yellow pickerel, northern pike and smallmouth
bass and good for panfish. Yellow pickerel
fishing is particularly good during the early
morning and evening hours.
Access and Facilities
Hotel, motel, and camping facilities are
available in and around Perth.
To reach Patterson Lake leave Highway 7 at
Perth and travel north on County road No. 1,
13.9 miles to County road No. 8 at Watson’s
Corners. Drive west on No. 8 5.6 miles, then
turn north onto the fifth concession line of
Dalhousie Township. The south-west corner of
Patterson Lake is 2 miles north on this
Survey Dates July 15-16 1968 – June 3, 1969
The above information is valid as of June 1969.
Conditions subject to change.
In my opinion the directions are wrong – the 5th
will take you into the south-east corner and not
the south-west. I left all the information in
imperial measurements to make the day for
Dave MacCrimmon – Lorne
Any Other L&F Maps?
If there are other pre-1990 L&F or MNR maps,
or really any old information data about
Patterson Lake, we would really appreciate it.
All we need is the data itself and the name of
the reference source. If we use it, we will give
full credit to the original source.
Annual General Meeting
We had a smaller turnout to our AGM, but it
was a very productive meeting.
We accepted the audited financial statement,
and held elections to the Board. All of the
previous Board were elected, and we will
confirm everyone in their same positions at our
next Board meeting.
We put in place the new set of by-laws, and I
was very pleased to have it moved by Kathleen
Sullivan and seconded by Ken Potter, the two
other workers on the committee. It is a good set
of articles and by-laws. This set is up on the
website and that is the official set. It does not
exist in any other format except the website
format. Anyone wishing hard copy can simply
The meeting was over in an hour, and we had
time at that point for everyone to introduce
themselves. The meeting was opened for a
general discussion on anything that was
bothering the members. Speeding boats too
close to shore came up again.
The 2007-2008 membership dues were set at
$20 per property owner. If you have not paid
the dues for this year, we would really
appreciate it. Next summer we will start our set
of Lake Management Plan meetings and will
have to rent a hall.
If the support is sufficient, I would like to have
our own domain name registered (I would try
www.pattersonlake.ca) and have it hosted, but
that costs about $150 per year. At present I am
hosting it on www.bowerman.ca, but I don’t go
on forever. As well we are sending the
newsletter out to all property owners regardless
of whether they paid dues or not. We hope to
convince our lake neighbors that it is the best
$20 they will spend this year.
Please send your cheque to our Treasurer:
313 Hinchey Ave
Ottawa, ON K1Y 1M1
For those who have already paid, your receipt
in included in this mailing.
The Septic Office and Patterson Lake
In the last newsletter I noted Jamie Saunders
and the Sewage System Re-Inspection Program
that operates from the MVC headquarters. I
also noted that Lanark Highlands is not part of
the program. I emailed Leonard Echlin and
received the following reply to Leonard from
We do not have a reinspection program.
Tay Valley Twp. contracts with the Rideau Valley
Conservation Authority to do a fixed number of
targeted reinspections each year. We have talked
about this at Council in the past but there has been
no appetite to proceed.
This is an issue that we can discuss
budget as it has financial implications.
In my judgement I would like to see it put in
place as it is one more tool that can be used to
keep our lakes clean. I will continue to follow
A Time to Brag
The regulars at 151 Lakeside Rd started the
Thanksgiving weekend a day earlier and we
went up on October 5th. The water at that point
was about 21° at the dock. That is good enough
to swim. So the well insulated, not so well
insulated, and completely uninsulated residents
went in for a swim. It was really a summertime
swim. About one metre down the water was
about 18° so if you kept near the surface, it was
That is the latest that I have ever been in for a
swim. It may speak volumes about global
Lake Management Plan
I mentioned earlier that we will start our data
gathering for the lake as it is now. When that
process is finished, we will be able to look back
at earlier records to see how things have or have
The things that leap out first are things like fish,
aquatic plants, trees, and birds. We have an
immense amount of talent around the lake and
the hope is to use that talent to do the program.
Paying someone to do it is a waste in my
judgement. I think our lake neighbours as well
will want to see their name in the report as a
symbol to our grands and great-grands that we
cared for and loved this lake.
We haven’t got all the details worked out yet but
a good guess will be that the various interest
groups will meet together, most likely at the
Watsons Corners Hall, next year, break into
groups and work on the areas of interest. I
would think we will start off with the four listed
above. We will grow from there.
As a start, I have listed below the fish, aquatic
plants, and timber from the 1961 L&F map.
Smallmouth Bass, Yellow Pickerel, Northern Pike, Bluegill, Perch, Rock Bass,
Pumpkinseed, White Sucker, Walleye
Chara, Milfoil, Sweet Gale, White Water Lily, Yellow Water Lily, Smartweed, Curly-leaf
Pondweed, Narrow-leaf Pondweed, Bulrush Cattail, Bladderwort, Tape Grass
Birch, Cedar, Elm, Maple, Oak, White Pine, Spruce.
I noted earlier that the 1961 map had the
distribution in and around the lake for the
aquatic plants and timber. I would hope we
could look at what it is today.
Connie and I are long time birders and we have
a list of the birds that we have seen at Patterson
Lake. However, it is in our cottage log book
and not available for this newsletter.
If we have others interested in rocks, reptiles,
amphibians, algae, lichen, or whatever, please
let me know. The most knowledgeable
amphibians watchers I know are my grandkids
so don’t forget to ask the young ones about
their interest. It would be a hoot to sit and
watch a group of young people produce a list of
frog species for the lake.
I will finish off this newsletter by reporting that
the lake level is very low at this time, and
indeed, I have to go back to 1995 to find a
lower level, and that was in September. We
usually have about 10″ above the bottom of the
culvert instead of our present 1″. We are in
good shape for the winter freeze-up with a low
enough water level to reduce the risks of high
water damage in the spring. But I have to add
that the weather is completely unpredictable.
This Newsletter was written by Lorne
Bowerman. As usual, Connie did the proof
reading and polished it up a bit. Comments,
suggestions, or articles are welcome.