HomeMy WebLinkAboutPublic Works April 12 20051
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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
Public Works and Safety Committee
April 12, 2005
Committee Chair Barbara Brenner called the meeting to order at 1:10 p.m. in
the Council Chambers, 311 Grand Avenue, Bellingham, Washington.
Present: Absent:
Sam Crawford L. Ward Nelson
Also Present:
Dan McShane
Seth Fleetwood
Laurie Caskey- Schreiber
COMMITTEE DISCUSSION
1. PRESENTATION REGARDING LAKE CIRCULATORS, A POTENTIAL
OPTION FOR HELPING TO CLEAN UP LAKE WHATCOM (AB2005 -174)
Chris Knud- Hanson, SolarBee Pump Systems, Inc., stated he is a limnologist
and a member of the North American Lake Management Society. He submitted a
Power Point presentation (on file) and read from the presentation outline and
natural food production in lakes. A lot of the oxygen produced in the upper waters
are produced photo - synthetically by the algae. The algae can either be consumed
by zooplankton or can decompose. Oxygen can be consumed by decomposition.
A lake or body of water will lose heat to radiation if the air is cooler than the
water body. Water will warm from solar energy if the air is warmer than the water.
When lakes don't freeze over during the winter, there is one long period of mixing.
Fall through spring, the temperature is the same top to bottom. There is little
resistance to mixing. It will mix until late spring when the surface water heats up
enough so that the lake doesn't mix all the way to the bottom. In the summer, on
the top level of water mixes. The rest remains isolated the rest of the summer,
until fall. The epilimnion is the water above the thermocline. The hypolimnion is
the water below the thermocline. In Lake Whatcom, the thermocline is around 12
meters.
He read the presentation on the SolarBee up -flow circulators. An impeller in
the dish draws up water through the tube. A bottom plate prevents water from
being brought up from the bottom. The water enters into the unit laterally. The
dish spreads the water back out laterally. There are three solar panels and three
floats. The unit can be anchored to the bottom of the lake.
Public Works and Safety Committee, 4/12/2005, Page 1
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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 asked if it is important to get below the thermocline, and could
they make the hose that deep. Knud- Hanson stated it is important, and they try to
stay above the thermocline, not below it. They can make the hose as long as they
want. The dish promotes long distance circulation. The large machine moves
about 10,000 gallons per minute, with very little lift. The water is not moved out of
the lake. The depth is not an issue. The temperature is an issue.
Caskey- Schreiber asked if it will break the stratification. Knud- Hanson stated
it depends on the application. The focus is on the blue -green algae.
Caskey- Schreiber asked if he advocates for having an intake closer to the
surface to not suck up the sediment. Knud- Hanson stated they will suck up
sediment regardless. In the summer, it could bring up anoxic water that is nutrient
rich. That could fertilize the upper waters, which is the opposite of what they're
trying to do.
He read the difference between wind versus SolarBee mixing. Wind doesn't
mix the water column. The SolarBee continuously moves the water column up
from the depth and distributes it outward in a continuous motion.
He read the presentation regarding lakes and reservoirs and the four distinct
problems addressed with SolarBees.
Brenner asked the difference between blue -green algae and other types of
algae. Knud- Hanson read the presentation regarding blue -green algae bloom
control. The blue -green algae don't reproduce quickly, but one nice sunny day can
create a bloom. These things have been trying to regulate their buoyancy during
the wind and rain. When the weather calms, they come to the surface. They come
to the top, photo- oxidize, die, then float to the surface. The surface scum is mainly
dead blue -green algae. Nothing eats it so it sits there. The big factor is that it is
not eaten.
He showed examples of the blue -green algae. These have a very time with
the water circulation because the circulation disturbs their habitat. He continued to
read the presentation on blue -green algae control. The nitrogen and phosphorus
coming into the lake will go into the edible algae if they remove the blue -green
algae. The water clarity will improve. The productivity improves all the way up the
food chain. This happens regardless of the nutrient concentration, even in
wastewater lagoons.
He showed a diagram of the blue -green algae bloom control using the
SolarBee. At a rate of 10,000 gallons per minute, 3,000 gallons go up the intake
laterally and 7,000 gallons is induced flow going up the sides. The spacing for the
large machine is about 50 acres. Oxygenated water is being dragged down to the
depth of the intake. Sediments are also getting oxidized. There is no buildup of
blue -green algae to smother the sediments. This circulating pattern controls the
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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.
blue -green algae. They've seen this happen consistently in over 80 water bodies.
They've never seen the reverse happen.
The original machine was for wastewater lagoons, sludge control, ammonia
control, and other benefits. As a side effect, they found that the unit controlled the
blue -green algae and other contaminants. The form of nitrogen is important to the
milfoil and other plants. It turns out, these plants only use ammonia instead of
nitrate. The circulation oxygenates the sediments and turns ammonia into nitrate.
It effectively starves the plants of nitrogen. They are controlling aquatic plants
through nutrient control, and controlling blue -green algae through habitat control.
He read about the symbiotic relationship between blue -green algae and
aquatic macrophytes.
Caskey- Schreiber stated they are taking oxygen from the air and putting it
into the lake. There are high nitrogen levels in the air. She asked if that changes
the formula. Knud- Hanson stated those blue -green algae that can fix nitrogen only
do it when there is a depletion in the water.
April Markiewicz, Bellingham, stated that in a lake system, phosphorus and
nitrogen go into the system. There is regular green algae that feed off the
phosphate and nitrogen. The phosphate becomes limiting and nitrogen is left in the
water. The blue -green algae use that nitrogen from the water and the air. The
green algae are in stasis. They have no phosphate. The ratio of the phosphate and
nitrogen is not conducive to them growing. Regular air, with 78 percent nitrogen,
incorporates a lot more nitrogen into the water and back to the green algae. With
the continued influxes of phosphate into the lake from development and
stormwater runoff, there becomes more nitrogen and phosphorus in a ratio
conducive to the blue -green algae, but not the green algae. In essence, the
productivity shoots way up in any lake system. For Lake Whatcom, they are trying
to decrease productivity, which is already too high. The oxygen levels in the upper
limnion are at nine to 11 milligrams per liter, even in September. There is no
oxygen depletion in the entire upper limnion. Studies have shown that the lake is
fully circulated and oxygenating. A system like this would be more detrimental by
incorporating more nutrient into the system.
Knud- Hansen stated the nitrogen in the air is not a factor for non - blue -green
algae.
Markiewicz stated significant studies show that incorporation of air into a lake
will increase significantly the nitrogen concentration that leads to fish poisonings.
It eliminates a lot of the blue -green algae, but it's not an issue in this lake. They're
trying to control productivity, which is an issue in this lake.
Knud- Hansen stated a bigger issue is where the productivity is going. The
nitrogen affecting fish is right. However, atmospheric nitrogen has no impact on
alga speciation. It's more about the ammonia. Productivity will be controlled or
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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.
limited by the availability of the element in least supply relative to the needs,
whether it's temperature or nutrient limitations. Generally it's nitrogen or
phosphorus. Ammonia can come in through nitrogen fixation. Through blue -green
composition, it becomes a nitrogen source indirectly. Lake Whatcom is still
phosphorus limited, but not all lakes are. Thirty years ago, the problem was only
phosphorus. Now, with the effects of increased population, nitrogen has become a
problem as well. He continued to read the presentation on the fishery benefits.
There is a difference between production and productivity. Productive is the rate at
which biomass is being created. Production is what they see at one point in time.
One of the most productive ecosystems is a coral reef, but the production is low.
They're seeing a reduction in the algal biomass, which improves water clarity, but
the productivity may increase.
If they lower the intake below the thermocline, which is not a consideration
for Lake Whatcom, it will bring cooler and denser water up the uptake. However,
the cooler and denser water will fall back down. It is not as effective for blue -green
algae control in lakes bigger than 15 acres. It's a way of getting oxygen to deeper
waters without destroying the thermocline, but it's a slow process. For drinking
water reservoirs, the SolarBee intake is above the thermocline, except near the
drinking water intake. Near the drinking water intake, the SolarBee intake is set
lower to keep that water oxygenated to prevent manganese and iron from getting
into it. He read the presentation about the inorganic chemical release prevention.
Lowering the SolarBee has a way to bind phosphorus and keep it in the sediments
without chemicals, such as alum.
Caskey- Schreiber asked if the circulator would stir up the phosphates at the
bottom of the lake for feed to the blue -green algae when it uptakes water from the
bottom. Knud- Hanson stated it's a timing issue. The SolarBee would be set up in
the winter or spring. They can't install it during the middle of summer.
(Clerk's Note: End of tape one, side A.)
McShane asked whether added alum relates to iron releases. He asked if it
prevents an iron and manganese release. Knud- Hanson stated it doesn't. It's a
function of oxidation reduction potential. Alum and other lake management
techniques address the symptoms.
McShane stated the alum will grab the phosphorus, but the iron can still be
released. Knud- Hanson stated sediments are often high in iron anyway. The issue
is whether the iron becomes soluble again. The alum will bind up the phosphorus
that would have otherwise gone to the blue -green algae, which have otherwise
decomposed, settled on the bottom, and made iron more available. Indirectly there
would be a positive effect.
Knud- Hanson continued the presentation about air bubbler comparison.
When installed deep, they do the same thing as a SolarBee. Wastewater operators
install air bubbler, but it creates a great amount of horsepower. An air bubbler is
Public Works and Safety Committee, 4/12/2005, Page 4
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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 form of an aerator. Part of the intent is to get oxygen to the lower waters, but
it's not efficient. The trouble is that bubbles rise, so they really don't effect the
sediments. He continued the presentation on an example from East Gravel Lake 4
in Thornton, Colorado, including the 2003 temperature profiles and the total
algae /blue -green algae monthly average from 2001 to 2004. The SolarBee was
installed in the Spring of 2003.
Bruce Roll, Assistant Director, asked if the system in Thornton, Colorado
experienced a change in the trihalomethanes (THM) potential and a decrease in the
distribution system. Knud- Hanson stated he doesn't know, for Thornton. The next
example from Palmdale, California, measured THM's. Anecdotally, they are seeing
a reduction in THM's. They are being caused by decomposing blue -green algae. By
eliminating the amount of organic suspended solids, they're seeing a reduction of
THM's. There hasn't been a study specific for THM. The drinking water utilities has
provided the data.
Roll stated Lake Whatcom basin three is over 300 feet deep and does not
have as severe an oxygen issue at this point. He asked where the drinking water
intake should be to insure that the water is the most consistent, high quality water
with the least amount of influences from the more productive portions of the lake.
Knud- Hanson stated it's a trade off with how much water they need. If need were
not the main issue, keep the drinking water intake above the thermocline to
eliminate any problem with hydrogen sulfide, iron, or manganese. The thermocline
is a function of wind exposure. A small, protected lake will have a shallow
thermocline.
Markiewicz stated it is a thermal boundary. Warmer water that is lighter
floats on top of colder, denser water. Therefore, the thermocline is a little zone
between the two. It can be depressed by a vetch of wind coming through. The
depth of the thermocline has to do with temperature. Knud- Hanson stated he
disagrees. On a warm spring day, the radiation from the sun goes into the water
column about one meter. That's all. What distributes that heat is wind mixing.
How far that heat goes down depends on the wind energy that is there.
Markiewicz stated the wind moves the heat through the epilimnion layer, but
the level of it is stable over time. Through all three basins, it's 12 to 15 meters.
Knud- Hanson stated that a very small, deep lake would have a thermocline that is a
lot higher than a lake like Lake Whatcom.
Markiewicz stated they are saying the same thing, from different
perspectives. She doesn't see how a circulator will do that much good for Lake
Whatcom. It won't prevent pollution. Blue -green algae is a problem, but not a
major problem. The money that would be spent on circulators could be better
spent on trying to prevent pollutants from entering the lake. Don't have a system
that might potentially add more nutrients by the influx of nitrogen into the water
and pull contaminants into the upper limnion, causing fish kills or re- suspending
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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.
mercury or other nutrients. Circulating the upper limnion is not an issue for Lake
Whatcom.
Knud- Hanson continued the presentation on an example from Lake Palmdale
in California. There are recreation activities in this lake, which has seven
SolarBees. In Lake Whatcom, blue -green algae dominates the algal population
during the summer. It is a concern. It was a much greater concern in Lake
Palmdale. The goal was to maintain a chlorophyll threshold at 15 micrograms per
liter. In 2002, they weren't able to do that. They put in about $65,000 worth of
copper sulfate, and they still weren't able to knock down the algae because it
resisted and adapted to the toxicity. The problem got worse. When the SolarBees
were installed, the chlorophyll level dropped. He showed the graphs on chlorophyll
and temperature and zooplankton levels and a data summary for Palmdale Lake.
In this lake, there has been improved fish spawning.
He continued the presentation on composite conclusions for the application of
SolarBees in freshwater lakes and reservoirs. With nutrient input, warm surface
waters are the preferred habitat of blue -green alga's. Because of their toxins, they
affect biodiversity in the water column. They don't see any other species of algae.
When the blue -green algae species is not edible, there are surface scum and odors.
They sink to the bottom and decompose, which adds biochemical oxygen and
promotes anoxia, fish kills, and sediment release of iron, manganese, iron, and
hydrogen sulfide. The decomposition also adds ammonia nitrogen to sediments
that promote macrophytes. Blue -green algae can add nutrients to the lake in
several ways. All these problems will occur, even if copper sulfate is added. The
trick is to try and prevent them from growing.
He continued to read the presentation on the lake process with SolarBees,
which horizontally and vertically circulate the epilimnetic waters. They disrupt the
blue -green algae habitat and oxidize littoral sediments. When the biomass is eaten
in the upper water column, it doesn't settle to the bottom to decompose. The less
organic matter at the bottom, the more oxygen they can save. They are indirectly
addressing the oxygen problem in the lake. Circulation is healthy for anything, to
prevent stagnation.
There are benefits to public health and economics in other ways. He read
the presentation on the additional lake management benefits of the SolarBee
circulation.
McShane asked if the SolarBee has any effect on the oxygen flow below the
thermocline. Knud- Hanson stated it does, indirectly. By reducing the biomass
going to the bottom of the lake, the rate of oxygen depletion is reduced.
McShane stated they are creating a more productive system on the upper
part of the lake. As long as there is outflow or some sort of production being
removed from the lake, it will reduce loading during that period of time. He asked
if the SolarBee would turn on after the thermocline is set. Knud- Hanson stated that
Public Works and Safety Committee, 4/12/2005, Page 6
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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.
if they can get in the lake by early spring or summer, they're okay. It depends on
how deep the light penetrates. They can't get in a SolarBee during the middle of a
bloom. If the SolarBee intake is set at about the level of the thermocline, it can
almost establish the thermocline itself. It can play some role in the depth of the
thermocline.
McShane asked if it can play a role in the temperature below the
thermocline. Knud- Hanson stated they can. They would need more units. It is
likely not cost effective to do that. If it's on during the day, it can cool the surface
water and reduce evaporation. They can play with the temperature that way.
Generally, it's not something they do. In most cases, the real problem is blue -
green algae blooms. Phosphorus is not a problem. It's a necessary dietary item.
The problem is with the plants that take up that food. The blue -green algae have
found ways to out - compete other algae for that food. When that happens, the
consequences are oxygenation and loss of biodiversity. Redirect that phosphorus
to edible algae so it is no longer a problem. It's tough to control phosphorus
coming into the lake.
Caskey- Schreiber stated there is value in this kind of system for lakes or
reservoirs with internal loading problems. Lake Whatcom has external loading
problems, so she's not sure this system is a viable way to treat Lake Whatcom.
She asked the largest lake or reservoir SolarBee has treated, and at what cost for
installation and maintenance. Knud- Hanson stated external loading is what comes
in from the watershed. Internal loading is the phosphorus that gets into the water
column during the summer when the bottom water goes anoxic. For most lakes,
that internal loading doesn't come into play until the lake turns over. For Lake
Whatcom, the summer blooms is due to external loading. The stormwater inputs
are a major source of nutrients during the summer.
The largest lake with SolarBee units is about 500 acres. At 50 -acre spacing,
ten units are required. The units are about $40,000 each, installed. Maintenance
is virtually zero. He recommends one unit per 50 acres. Basin one is a better place
to start in Lake Whatcom. He would not consider them for basin three at all. It's
too big. They can affect portions of a lake. They are installed in high- target and
high -use areas. Blue -green algae are generated among the shorelines. The main
body of a lake is a low priority. Generally, the machine is designed to last for 25
years or longer. The new magnetic motor does not have brushes, so no
maintenance is required. There is an electronic board that monitors SolarBee
operating data. Because the new model solar panels are so efficient, the SolarBee
has an on -board battery. The machine runs off the battery, not the solar panels.
The only problem is getting the bugs out of the computer board, which the
company repairs at its own cost. The SolarBee is not maintenance -free, but it's
close.
Caskey- Schreiber asked if they are lit up at night for boating traffic. Knud-
Hanson stated they can be equipped with Coast Guard approved beacons and lights
that meet state and federal requirements.
Public Works and Safety Committee, 4/12/2005, Page 7
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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 asked for Mr. Knud - Hanson's advice on how the Council makes a
political decision on something like this. Some people will automatically be
opposed to this unit because they think it treats a symptom, not the problem. He
asked how the Council gets people out of that mindset if they say the main issue is
not phosphorus, but lake circulation.
McShane stated Lake Whatcom is listed as an impaired body under section
303(d) of the Clean Water Act. It's not just a political issue. Legal issues will have
to be addressed as well. The total maximum daily load (TMDL) study is about the
rate at which dissolved oxygen drops off in the lower part of the lake. The County
is faced with a TMDL permit. Other things may be added.
(Clerk's Note: End of tape one, side B.)
Crawford asked if this is a viable approach that government should take.
They hear that a stormwater fix for one neighborhood will cost $8 million. That's
just for one small area. He asked the process observed in the past for making
decisions on this. Knud- Hanson stated the process observed is different from what
he would recommend. Keep focused on the exact problem. The problem in these
ecosystems is the blue -green algae. The oxygen is a response to the blue -green
algae. It's a symptom of organic inputs to the bottom waters. They have an
oxygen deficit because organic matter is going to the bottom of the lake. Organic
matter is going to the bottom of the lake was produced within the lake. Nothing
eats the blue -green algae, so they will go down to the bottom of the lake.
Blue -green algae need light, temperature, nitrogen, phosphorus, and
oxygen. They can't control the light, temperature, and carbon. They can only
modify the availability of nitrogen and phosphorus. The way to control algae is to
limit phosphorus input to the lake. The phosphorus will still get in and cause some
deoxygenation. If oxygen is the problem, do something proactive to minimize the
amount of organic matter from going to the bottom.
Crawford asked if SolarBee offers a money -back guarantee. Knud- Hanson
stated there is a performance bond. Normally, SolarBee is brought in to clean up
very dirty water. The people around most of those lakes would like to have the 15-
feet of visibility that Lake Whatcom has.
Crawford stated he talked to an aeration company, but they lost interest
because there isn't much to fix. Knud- Hanson stated aeration can be part of the
problem. Aeration won't work with Lake Whatcom. In addition, aeration devices
have a lot of operating costs and noise.
There is some truth to construction not being an issue. There is also an
issue of turbidity and suspended solids. Focus on the issues that a mitigation
approach is supposed to address.
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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.
Fleetwood asked how long the SolarBees have been around. Knud- Hanson
stated they have been around since 1998. The company has been around since
1978, in the pump business.
Fleetwood asked if anyone has ever reported unintended consequences of
the SolarBee. Knud- Hanson stated in two cases, the photic zone got so clear that
the algae were growing underneath. The company realized the problem and
corrected it.
Fleetwood asked if there is a process to do a cost - benefit analysis to
determine if this is the best choice. Knud- Hanson stated his choice is to do it over
a 20- to 25 -year horizon, after the initial capital cost and including annual operation
costs. As energy costs go up, aeration gets more expensive. There are more
tabular comparisons available.
Crawford asked if Mr. Knud- Hanson could prepare a specific proposal for
Lake Whatcom. Knud- Hanson stated he would ask the Council what problem and
concerns should be addressed.
Crawford stated the Council is told that the depletion of dissolved oxygen is
the problem, specifically in basin one, somewhat in basin two, and possibly in the
future for basin three. Knud- Hanson stated SolarBee can fix it. Deal with the blue -
green algae first, as the primary source of oxygen- demanding substances going to
the bottom of the lake. The lack of oxygen at the bottom, in and of itself, is not a
problem. It becomes a problem when there is enough antioxidant to cause fish kills
and taste and odor problems. Ecologically, it's not a problem itself. SolarBee
would look at basin one first. There could be one SolarBee in deep water near the
intake, but don't do all of basin two. Clean up basin one first and see how SolarBee
works. The SolarBee would be used as preventative maintenance, so the water
clarity doesn't decrease further.
McShane stated he's impressed with the SolarBee presentation. Water
moves out of basin one and into basin two during the productive time in the
summer. He would be concerned about productivity being exported into basin two.
Knud- Hanson stated another case was a lake that had blue -green algae imported
from an adjacent lake. If they are treating basin one, the water going into basin
two won't be a problem. The productivity will likely increase because the blue -
green algae don't grow as fast. The actual biomass will decrease. The water from
basin one should have a lower biomass and the nutrients no longer become an
issue. In one case, SolarBees were used just around the intake. Unfortunately, it
didn't work. They learned from that experience that to really control blue -green
algae, they have to control the whole lake.
Fleetwood stated this device presumably seeks to create conditions that once
existed in nature. He asked if they would remain reliant on a SolarBee forever, or if
there would come a time when the SolarBee is no longer needed. Knud- Hanson
stated he's not sure about going back to nature. Blue -green algae have existed for
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two and a half billion years. A blue -green bloom is natural. It's increased over
time because of nutrient availability. If they cut off all the nutrient input, then they
won't need the SolarBee. Without making changes to nutrient loading, the
problems will return.
Brenner asked what would happen if they decide to use the SolarBee as an
interim solution while the County does long -term activities to reduce or eliminate
the loading sources. Knud- Hanson stated it depends on the politics and cost -
benefit. SolarBee units can be rented instead of purchased. It allows time to see if
the unit works. There is a one year minimum rental policy. If the unit is not doing
the job, the company doesn't want them in the lake, either.
Andrew Craig, Washington State Department of Ecology, asked for a copy of
the presentation. He liked the physical and biological approach. The concept is
thought - provoking. He asked about how effective is the plate placed at the bottom
of the SolarBee, which is supposed to prevent water from anoxic areas being drawn
up through the circulation. He asked if it is 100 percent reliable. He wouldn't want
to see a SolarBee replicate the bubble method. Knud- Hanson stated that if that
started to happen, they can just raise the intake. There is an immediate fix. The
Public Utility Commissions in San Francisco has a 90 million gallon tank that is
being successfully mixed, top to bottom and corner to corner.
Craig asked the degree of mixing that can happen between the epilimnion
and the hypolimnion. He asked if the timing varies by water body. Knud- Hanson
stated it has more to do with location and climate. The SolarBee should be in
before the blooms.
Craig asked if the volume of the water body makes a difference. Knud-
Hanson stated it does not, for blue -green algae. It has more to do with the depth
of the photic zone and the depth of the thermocline, than the depth beneath the
thermocline.
Robin Williams, Ferndale, stated she's seen the City's and County's feasibility
studies on different things. She asked the number of units necessary for basin one
and the least cost of each unit for one year. Knud- Hanson stated basin one is 450
acres. The morphology is not too dendritic. There could be nine or ten units total.
The rental cost is $900 per unit per month. There is an installation fee of about
$4,000 per unit. With that many units, there would be an installation discount.
David Langley, 1404 Northshore Drive, Bellingham, asked if many people
complain about the appearance of the equipment on the water bodies. Knud-
Hanson stated some people just don't like it. However, they found out about the
benefits, such as improving the ecology and the good fishing around the SolarBees.
There is initial discomfort, but the homeowners end up accepting it. They don't
make any sound unless there is something wrong with the motor.
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Langley asked the quantitative effect of 1,000 geese from this lake on the
growth of the blue -green algae. Knud- Hanson stated the geese do add nitrogen
and phosphorus. The SolarBees would be beneficial to the impact, in theory.
However, most studies show that the contribution of nutrients by geese is not as
big as people really think.
Joyce Langley, 1404 Northshore Drive, Bellingham, asked how to keep jet
skis and boats from hitting them. Knud- Hanson stated there are markers. It
wouldn't be any different from a buoy in a channel. There are a federal- or state -
approved light, warning signs, and reflectors on the unit.
Brenner thanked Mr. Knud- Hanson for the presentation.
OTHER BUSINESS
There was no other business.
ADJOURN
The meeting adjourned at 3:15 p.m.
Jill Nixon, Minutes Transcription
ATTEST:
Dana Brown - Davis, Council Clerk
WHATCOM COUNTY COUNCIL
WHATCOM COUNTY, WASHINGTON
Barbara Brenner, Committee Chair
Public Works and Safety Committee, 4/12/2005, Page 11