It may seem early in the season to be thinking about water levels but not for us! We need to know what to expect in the months to come to be ready for what may, or may not, happen. Summer water levels tell us how much pier our customers will need and where to install boat lifts. With extreme highs come shoreline damage, extra pipe for longer legs and big, damaging waves. With extreme lows, not enough pier to get adequate depth, higher demand for pier sections and extra work setting boat lifts. We’ve seen both of these issues within the past ten years. So what can you expect for this coming summer?
In order to know where our water levels will be this summer, you have to look at the condition of the lakes in the winter. Our current ice concentration on the Great Lakes remains below normal. If you look at the pictures in reference A, you will see the difference between the ice formation in late January 2022 and 2023.
So why is ice important you might ask? The amount of ice and snow formed over the winter directly affects the water levels in our lakes and streams come summertime. Without snow, we don’t have the snowpack melt needed to refill our aquifers in spring. On average, the melt from the snowpack is responsible for one third of the ground water we see in spring. Even though we may not have much snow in our specific area, we benefit greatly from the connection of the Great Lakes. Heavy snow fall in southern Canada melts and fills Lake Superior which in turn flows into Lake Huron which is hydraulically connected to Lake Michigan. The more snow the better too because the ratio of snow to water is only 12:1, meaning you need about 12” of snow to generate 1” of water. As snowmelt fills our lakes and streams, ice protects them from evaporation and outflow. Statistically we have lost 30% of ice coverage on the Great Lakes since 1970. Reduced ice cover leads to increased evaporation and lower water levels, as well as an increase in water temperature and sunlight penetration. This has caused lake ice to form later than usual, about a day to a day and a half per decade. The rising surface water temperature has also affected “ice off” or the thaw dates for ice on the Great Lakes.Earlier ice off dates, which is currently about 24 days sooner since studies began in the early 1900’s, means the lake absorbs more heat over spring and summer perpetuating the late ice formation. Another effect of the warmer surface water, reduced ice cover, and increased evaporation is a corresponding increase in precipitation over nearby land, especially “lake effect” snow. This precipitation is depositing the water evaporated from the western lakes over eastern states starving the aquafers of the wester lake’s bordering states. A smaller role ice coverage plays is in the outflows of rivers and streams from the western lakes into the eastern lakes as they deposit into the Atlantic. The ice coverage helps reduce the flow of water between the lakes and without it, more water is flowing and depositing into the Atlantic throughout the winter without being replenished by icepack or precipitation.
Now that we know the condition of the lakes in winter, what can we expect this coming summer? Stay tuned for next months blog to find out what we are predicting for water levels in summer and what you can do to stay ahead of it.
Is a sway brace used on your dock? If not, does your dock sway as you walk on it? There are several reasons this can happen to any dock or pier.
There are main TWO reasons for dock movement.
You need to distinguish between the two types of movement. Is it an up and down movement, or is it a side to side movement?
First, Let’s tackle the Up and Down movement.
When installed, PWS makes sure the legs are firmly on the bottom. This typically makes the dock stable for most people.
Yet, over time, storms can wash out or move the sand or rocks under the footpads. Sand is more susceptible to this action.
It’s the same effect that erosion has on the shoreline. First, it washes away sand and small stones from under the footpad. Then, it continues to work on the remaining stones and rocks. When enough materials are removed, there is nothing left to support the leg.
At this point, you may experience the sensation of up and down movement as you walk.
How do we prevent it from happening?
There is no way to completely prevent washing out of the footpads. If we disturb the lake bottom too much, it weakens the tightly packed base. Disturbing the lake bottom makes it easier for the wave action to wash the sand away. The sand (or small stones) are loosely packed and have small openings in them.
The only “cure” is to reset the legs firmly on the bottom. We notice this frequently occurs after strong storms. The “white caps” you see are moving the water under the surface also.
The second type of movement is actual “sway.”
“Sway” is the side-to-side movement when the dock is set higher above the water.
The current water level is still above average even though it is down from 2019 and 2020. This is evidenced by the continued erosion happening up and down the shoreline.
PWS raises your dock up to protect it from high wave action during the summer. When the frames are adjusted higher, the pier becomes less stable. Walking on the dock will cause a side-to-side movement because the center of gravity is higher.
Think of a simple fishing pole. When the pole moves at the bottom, the movement is amplified at the top of the pole. The higher the frames are raised, the more side movement will occur.
A sway brace on the legs reduces the sway side sway. You’ll feel more secure as you walk the length of your dock.
Does every set of legs need sway braces?
No.PWS will make recommendations based on the heights and lengths of your dock or pier. Often, we add a single brace on a pair of legs. Next, we alternate the position in the opposite direction on the next set of legs.
One brace is attached near the bottom of one leg and clamped higher up on the opposite leg. This depends on the height of the legs.
It may involve a crew member having to submerge in the water to reach the bottom of the leg. In spring, that is not something anyone wants to do.
Does it matter if I have an aluminum or steel frame?
A steel frame is less likely to need braces than an aluminum frame due to its own weight. Different configurations are available for aluminum frames, but the principle is the same.
Braces are available for new installations, as shown here. There is an add-on version (independent components) for existing frames. They can be added to existing dock legs if needed. Either version will help stabilize your dock in deeper water.
Will sway braces help your dock?
Call Jerry at 920-493-4404 for more details.
Where is Pier & Waterfront Solutions?
Located at 7325 St. Hwy 57, it’s 3 miles south of Sturgeon Bay and 1 mile past the intersection of Cty MM (heading north). Look on the right side, one mile north, at the next corner (Idlewild Road and Hwy 57).
Is PWS OPEN?
Pier & Waterfront Solutions remains “open.” We have implemented measures to help ensure the safety of our employees and visitors.PWScontinues to work to maintain the trusted service that you have come to expect.
PWS implemented these preventive measures:
1. Conducting as much business as possible by email, text, or phone.
2. Site visits will continue. When in-person contacts are necessary, we will follow “social distancing” guidelines.
3. Our display yard is always open for you to examine at your leisure. All displays have a numbered, red tag on them. If you want more information or pricing, please reference that number.
What can YOU do to help us?
1. Please conduct as much business as possible via emails, messaging, and emails. This step protects everyone involved.
2. When you see our crews installing equipment, please practice “social distancing.” Remain at a safe distance.
Thank you for allowing us to work with you.
YES – PWS is OPEN and waiting for you!
Please call, message, or email PWS with any questions.