Here is some ice load information gathered from various sources. Please note that not everyone agrees on the safe ice thicknesses for various loads and that there are many variables to consider when determining if the ice is safe for the load you want to put on it. This post is just for general information purposes.
From the Army Corp of Engineers:
Every winter it becomes very important to know when the ice is safe to use. Here are some guidelines for determining the safety of freshwater ice. The following table of safe loads is valid ONLY for ice that is clear and sound, with no flowing water underneath. It is not reliable for stationary loads. When in doubt, stay off the ice !
It is highly recommended that you familiarize yourself with the Safety on Floating Ice Sheets information by CRREL.
Loads on Ice
|Required Minimum Ice Thickness in inches
||Description of Safe Moving Load
||One person on skies
||One person on foot or skates
||A group of people walking single file
||A single passenger automobile
||A 2-1/2 ton truck
||A 3-1/2 ton truck
||A 7 to 8 ton truck
Safe loads for clear solid ice are indicated below:
|Thickness of Ice
||Load or Activity
|< 1 3/4
||One person cross county skiing
||One person on foot or skates
||Snowmobile or smaller ATV, groups of people walking single line
||Person ice fishing, good for walking individual
||A small car
||A 2 1/2 tons truck
||A 3 1/2 tons truck
||A 7 – 8 tons truck
Note that ice strength is influenced by many factors
- age – newer black ice is stronger than old milky
- distance to shore – ice close to shore is weaker than ice farther out
- river outlets and inlets – ice close to outlets and inlets is weaker
- obstructions like rocks, trees and plants
- water currents
- cover of snow
This information must be used a general guide – keep off the ice if you are not absolutely sure.
12-4 Straight Slough Open Water Marking Map: red circles are open water, yellow lines are where willow markers with BLUE reflectors were spaced 15 feet apart. Straight Slough is 1,000 feet wide at the lower end and 1,200 feet wide at the upper end
Today an 11 person BSAR team marked off both ends of Straight Slough to discourage travel through that area. There are still three open holes in Straight Slough. This is more than we have ever seen in the Slough – especially in December.
Because of the unusual number of open holes, at Thursday night’s BSAR planning meeting it was agreed that it would be better to mark across the entire width of both the lower and upper ends of Straight Slough than to try to mark each individual hole. This is the first time that BSAR has completely marked off any part of the River in the Bethel area. We hope that this will send a clear message that the Slough should be avoided completely – for now.
Marking across the 1,000′ wide lower end
Marking across the 1,200′ wide upper end
BSAR would like to remind People that BLUE REFLECTORS MEAN OPEN WATER – STAY AWAY.
Part of the team: L-R Norman Japhet, Doug Lee, Charles Guest, Jack Beaver
Good work by a good crew. With the major danger in the Bethel area taken care of, BSAR will begin reaching out to our neighboring villages to assist them with open water marking in their areas. Any village SAR teams needing help, please contact BSAR.
Thank you to all that came out to help today.
CLOSE CALL CLOSE TO HOME: Boaters dragging for a snow machine that went into an open hole at the lower end of Straight Slough on December 1st. You can see Bethel in the background
Despite BSAR’s efforts to get the word out about the dangers of early season winter travel on the River, the word never reaches everyone and there’s some that don’t listen anyway.
On December 1st a snow machine with one adult and two children on board drove into the open hole at the lower end of Straight Slough.
We are very thankful that all three made it out of the water. The snow machine was lost.
BSAR will be working over the next few days to get this very dangerous area marked. Volunteers are needed.
Please help us get the word out: Travelers must avoid Straight Slough. Traffic above Bethel should use the trail around Joe Pete’s Bend to Church Slough.
Also with truck traffic opening up on the River, BSAR did some additional ice measuring along the route from Bethel to Napaskiak.
Ice thickness was consistently 10″ – 12″ thick. The top 2″ is snow ice which has less strength than good clear ice.
This thickness is considered marginal for trucks by experienced travelers. You can get away with it but please travel with extreme caution.
December 2 – Marginal Conditions for truck travel: Sample of ice taken right on the truck trail by Nick O. Nick’s old fish camp: this area was 11″ thick minus 2″ of snow ice = 9″ of good ice
Safe travels from BSAR
*Please note that this report is not an advisory that it is safe to travel. It is for informational purposes only.
Two open holes in front of Wassilie B. Evan’s camp. There are 30 open holes in Kuskokwaq Slough alone
Summary: Today BSAR members flew with Earl Samuelson to survey 60 miles of the Kuskokwim from Napaskiak to Tuluksak. With warm temperatures, strong southerly winds, and rain stalling winter again the Lower Kuskokwim River is no place to be traveling right now.
Over 50 open holes were counted along 50 miles of the River. In addition the recent storm has brought deep overflow to all parts of the Lower River affected by the tide.
MAJOR DANGER: Open holes at the upper, middle, and lower end of Straight Slough. This is looking upsream from the lower end
The darkness of open water: These large open holes are formed when the flowing ice jams in a narrow or shallow channel upstream
SMALL BUT DEADLY: The remainder of what was once a large hole. There are many of these smaller open areas scattered all throughout the River. A little cold weather will finish closing them up
Looking downstream at the upper end of Kuskokwaq Slough. This open hole is just around the bend from where we lost 3 people in 2014 (yellow arrow)
Closing: It was good to get up in the air with Earl again. We’ve missed working with him since he retired from the Alaska State Troopers last winter.
As you can see from these pictures no inter-village main river travel is recommended at this time. The glare ice with water on top makes it even harder to see the dozens of open water holes that are out there right now. A little cold weather will heal up the smaller ones then Kuskokwim SAR groups will start working on the bigger ones that will stay around for awhile.
Please be patient and if you must travel use the back trails.
And please don’t let anyone travel that has been drinking.
Thank you and Happy Thanksgiving from BSAR.
*This report is not an advisory that it is safe to travel. It is for informational purposes only.
Sample of ice from mid-channel near the Crowley fuel dock
With cooler temperatures and fresh snow People are getting anxious to get started on their usual winter activities.
A BSAR team did an initial assessment of ice conditions in the immediate Bethel area today.
The area assessed was from the upper end of Oscarville Slough to the lower end of Church Slough. This is what they observed:
Mid Channel straight out from the upper end of Oscarville Slough – 8″. There appears to be a well-traveled trail to Oscarville and Napaskiak using Oscarville Slough.
Bethel waterfront from Crowley to Brown Slough averaged 10″
The mouth of Straight Slough – 8″
10″ of mostly good clear ice along the Bethel waterfront
DANGER: STRAIGHT SLOUGH IS WIDE OPEN AT BOTH THE UPPER AND LOWER ENDS
Open water danger at the lower end of Straight Slough
Main River crossing to lower end of Church Slough – 8″ – No established trail through Church Slough at this time.
The safest and most heavily traveled routes from Bethel to the nearby villages is still by the back (overland) trails.
No open water is marked at this time and these dangerous areas are extremely hard to see in low light/low visibility.
As conditions improve Kuskokwim SAR trams will be working to mark the holes and established safe trails.
Additional updates will be provided as more information comes in. We hope to do an aerial survey before Thanksgiving.
Thank you & safe travels from BSAR
*Please note that this in not an advisory that it is safe to travel. It is for informational purposes only.
A New Role for BSAR: Hasty Team Delivers Fire Pumps to Upriver Communities: L- R Eric Pavil, Sam Samuelson, Norman Japhet, James Mute & Clarence Morgan
With wildfires threatening communities from Kalskag to Stony River and state firefighting resources stretched beyond capacity, BSAR responded to the call for additional fire fighting equipment by delivering four fire pumps and hundreds of feet of hose as far as Red Devil.
The BSAR hasty team made the 560 round trip from Bethel to Red Devil in less than 24 hours. They traveled through many miles of visibility less than 1/2 mile from the heavy smoke and areas where fire was actually burning right along the Riverbank.
These dedicated men traveled throughout the day and night stopping only for a short time in Red Devil to deliver the fire fighting equipment and eat. They finally took a short rest in Napaimute on the down bound trip early Friday morning.
Great work by a great crew.
The People Upriver wish to extend a big thanks to BSAR – especially Mike Riley, Earl Samuelson, Sam Samuelson, Norman Japhet, Clarence Morgan, Eric Pavil, and James Mute.
BSAR takes a quick look at the miles and miles of burned riverbank below Crooked Creek