Bainbridge Currents for Sept 12, 2015


Tom Kreyche
 


Steve - yes, you are correct it's about 15 mi CCW to Agate from Ft. Ward...Tom


From: "Steve Bennett"
To: "tkreyche" , "SoundRowers"
Sent: Thursday, September 10, 2015 9:03:31 AM
Subject: Re: [SoundRowers] Bainbridge Currents for Sept 12, 2015


Tom,
Nice work.  I defer to your analysis. You have caught my error:  I either foolishly or mistakenly equated the flood at Agate and Rich. Slack at Rich is over an hour later at noon.  The tide is at ebb in Rich until then. 
I think the Counter-Clockwise distance to Agate Bridge from Fort Ward is 15 miles, however.
 
Steve


Steve Bennett
 

Tom,
Nice work.  I defer to your analysis. You have caught my error:  I either foolishly or mistakenly equated the flood at Agate and Rich. Slack at Rich is over an hour later at noon.  The tide is at ebb in Rich until then. 
I think the Counter-Clockwise distance to Agate Bridge from Fort Ward is 15 miles, however.
 
Steve

From: "'Tom Kreyche' tkreyche@... [SoundRowers]"
To: 'Steve Bennett' ; SoundRowers@...
Sent: Wednesday, September 9, 2015 10:47 PM
Subject: RE: [SoundRowers] Bainbridge Currents for Sept 12, 2015

 
Steve,
 
Here’s my revised analysis based on a start at Ft. Ward at about 9:45 and a 4 hour racer. This disagrees with yours a fair bit, except we’re both suggesting CW would be best if the predicted N wind sticks.
 
Any other opinions?
 
…Tom
 
Overview
This estimate is for Saturday September 12, with racers starting from Fort Ward. Without considering wind, CCW may be more favorable since racers will spend less time fighting the current in Rich Passage. CCW may also have a slight advantage with the current through Agate Passage. However winds are forecast to be out of the N, which would tip the balance towards CW direction. The 9-mile E side of the island is exposed and a downwind leg is preferred.
 
Counter-Clockwise
A 3kt ebb will push racers to a quick exit from Rich Passage. On the S and SE end of the island a weak ebb will be beneficial. By the time racers reach Agate Passage (11 miles from the start) at about 11:15 a.m., they will be aided by a weak but building flood of 1.5 to 2kt. The current will aid racers on the NW side of the island, and transition to hindering them on the SW side as the flood into Rich Passage takes effect. A 2kt flood tide will hinder the entrance into Rich Passage with it weakening to 1kt near Ft. Ward.
 
Clockwise
Racers will immediately face a 3kt ebb through Rich Passage, and will also be hindered around the SW side of the island. The W and NW should be mostly slack. The entrance into Agate Passage is about 15 miles from the start - it is slack at 10:47 and builds rapidly to flood. Early arrivals will see slack or a light flood, but later arrivals will face 1.5 by 11:30 a.m. A weak flood will aid racers on the E side of the island and back into Rich Passage. One strategy would be to work hard the first part of the race to get out of Rich Passage and through Agate early, then cruise downwind on the E side of the island.
 
Tidal Currents
Agate Passage N End - Flood Direction, 230 True, Ebb (-) Direction, 032 True
Max Current -2 kt (ebb) at 7:44 a.m.
Slack Water 10:45 a.m.
Max Current +1.7 kt 2:03 p.m.

Agate Passage S End - Flood Direction, 216 True, Ebb (-) Direction, 037 True
Max Current -3.9 kt (ebb) at 7:56 a.m.
Slack Water 10:48 p.m.
Max Current 4.2 kt (flood) 2:10 p.m.

Rich Passage W End - Flood Direction, 238 True. Ebb (-) Direction, 055 True
Max Current -3.4 kt (ebb) at 9:05 a.m.
Slack Water 11:29 a.m.
Max Current +3.2 kt (flood) at 2:55 p.m.

Rich Passage Off Pleasant Beach
Max Current  -3.1 kt (ebb) at 9:26 a.m.
Slack Water 11:59 a.m.
Max Current 1.7 kt (flood) at 2:48 p.m.
 
 
 

From: Steve Bennett [mailto:bennett_seattle@...]
Sent: Wednesday, September 09, 2015 4:43 PM
To: tkreyche@...; SoundRowers@...
Subject: Re: [SoundRowers] Bainbridge Currents for Sept 12, 2015
 
So then, with the start now at Fort Ward, our hat is cocked; the tables turned.  Here's my new read:
 
Leaving Fort Ward, clockwise, within an hour of slack, a 5 hour racer should arrive at the Agate Pass Bridge with a favorable current of 2 kt, and slower paddlers will benefit even more.  Had he opted for counter-clockwise he would be fighting 3.5 kt at the bridge.  There'll likely  be no contrarians this year.
 
Also for your planning:
 
·         It is 15 miles from Fort Ward to the Agate Pass Bridge counterclockwise.
·         It is 11 miles from Fort Ward to the Agate Pass Bridge clockwise
·         Halfway is at about the middle of the big bay that extends from Agate Point to Point Monroe (which is just around the corner to the north from Fay Bainbridge)


    Any other thoughts ?
 
Steve




Tom Kreyche
 

Steve,

 

Here’s my revised analysis based on a start at Ft. Ward at about 9:45 and a 4 hour racer. This disagrees with yours a fair bit, except we’re both suggesting CW would be best if the predicted N wind sticks.

 

Any other opinions?

 

…Tom

 

Overview

This estimate is for Saturday September 12, with racers starting from Fort Ward. Without considering wind, CCW may be more favorable since racers will spend less time fighting the current in Rich Passage. CCW may also have a slight advantage with the current through Agate Passage. However winds are forecast to be out of the N, which would tip the balance towards CW direction. The 9-mile E side of the island is exposed and a downwind leg is preferred.

 

Counter-Clockwise

A 3kt ebb will push racers to a quick exit from Rich Passage. On the S and SE end of the island a weak ebb will be beneficial. By the time racers reach Agate Passage (11 miles from the start) at about 11:15 a.m., they will be aided by a weak but building flood of 1.5 to 2kt. The current will aid racers on the NW side of the island, and transition to hindering them on the SW side as the flood into Rich Passage takes effect. A 2kt flood tide will hinder the entrance into Rich Passage with it weakening to 1kt near Ft. Ward.

 

Clockwise

Racers will immediately face a 3kt ebb through Rich Passage, and will also be hindered around the SW side of the island. The W and NW should be mostly slack. The entrance into Agate Passage is about 15 miles from the start - it is slack at 10:47 and builds rapidly to flood. Early arrivals will see slack or a light flood, but later arrivals will face 1.5 by 11:30 a.m. A weak flood will aid racers on the E side of the island and back into Rich Passage. One strategy would be to work hard the first part of the race to get out of Rich Passage and through Agate early, then cruise downwind on the E side of the island.

 

Tidal Currents
Agate Passage N End - Flood Direction, 230 True, Ebb (-) Direction, 032 True

Max Current -2 kt (ebb) at 7:44 a.m.

Slack Water 10:45 a.m.

Max Current +1.7 kt 2:03 p.m.


Agate Passage S End - Flood Direction, 216 True, Ebb (-) Direction, 037 True

Max Current -3.9 kt (ebb) at 7:56 a.m.

Slack Water 10:48 p.m.

Max Current 4.2 kt (flood) 2:10 p.m.


Rich Passage W End - Flood Direction, 238 True. Ebb (-) Direction, 055 True

Max Current -3.4 kt (ebb) at 9:05 a.m.

Slack Water 11:29 a.m.

Max Current +3.2 kt (flood) at 2:55 p.m.


Rich Passage Off Pleasant Beach

Max Current  -3.1 kt (ebb) at 9:26 a.m.

Slack Water 11:59 a.m.

Max Current 1.7 kt (flood) at 2:48 p.m.

 

Sources
http://www.deepzoom.com/index.html
https://tidesandcurrents.noaa.gov/currents15/tab2pc2.html#17

 

 

From: Steve Bennett [mailto:bennett_seattle@...]
Sent: Wednesday, September 09, 2015 4:43 PM
To: tkreyche@...; SoundRowers@...
Subject: Re: [SoundRowers] Bainbridge Currents for Sept 12, 2015

 

So then, with the start now at Fort Ward, our hat is cocked; the tables turned.  Here's my new read:

 

Leaving Fort Ward, clockwise, within an hour of slack, a 5 hour racer should arrive at the Agate Pass Bridge with a favorable current of 2 kt, and slower paddlers will benefit even more.  Had he opted for counter-clockwise he would be fighting 3.5 kt at the bridge.  There'll likely  be no contrarians this year.

 

Also for your planning:

 

·         It is 15 miles from Fort Ward to the Agate Pass Bridge counterclockwise.

·         It is 11 miles from Fort Ward to the Agate Pass Bridge clockwise

·         Halfway is at about the middle of the big bay that extends from Agate Point to Point Monroe (which is just around the corner to the north from Fay Bainbridge)



    Any other thoughts ?

 

Steve


Steve Bennett
 

So then, with the start now at Fort Ward, our hat is cocked; the tables turned.  Here's my new read:

Leaving Fort Ward, clockwise, within an hour of slack, a 5 hour racer should arrive at the Agate Pass Bridge with a favorable current of 2 kt, and slower paddlers will benefit even more.  Had he opted for counter-clockwise he would be fighting 3.5 kt at the bridge.  There'll likely  be no contrarians this year.

Also for your planning:

·         It is 15 miles from Fort Ward to the Agate Pass Bridge counterclockwise.
·         It is 11 miles from Fort Ward to the Agate Pass Bridge clockwise
·         Halfway is at about the middle of the big bay that extends from Agate Point to Point Monroe (which is just around the corner to the north from Fay Bainbridge)

    Any other thoughts ?

Steve



From: Steve Bennett
To: "tkreyche@..." ; "SoundRowers@..."
Sent: Tuesday, September 8, 2015 11:33 AM
Subject: Re: [SoundRowers] Bainbridge Currents for Sept 12, 2015

Thanks Tom, for a more thorough analysis than you would have gotten from me.   I totally concur with your call.  Here is my read:
If a 5 hour Marathoner took the counter-clockwise route, she would face almost no current at the Agate Pass Bridge with the Slack occurring at 10:47. At Point White, about half-way, she would have a supporting current of 1.5 kt, building through the pass.

If however, she opted for the clockwise route, she  would be fighting that same 1.5 kt current when she hit Point White, and facing an uphill 4 kt current at the Agate Pass Bridge.  Not a big choice this year.
Look forward to seeing you all on Saturday.  We'll have the usual soup and bread at the finish, also a nice selection of commemorative hats, thanks to Stoneway Concrete.

Tide charts attached, I think.

Steve


From: "tkreyche@... [SoundRowers]"
To: SoundRowers@...
Sent: Monday, September 7, 2015 6:10 PM
Subject: [SoundRowers] Bainbridge Currents for Sept 12, 2015

 
Here's my take on the tidal currents for next Saturday's race. I'm interested to hear other opinions.

...Tom Kreyche

Sources
http://www.deepzoom.com/index.html
https://tidesandcurrents.noaa.gov/currents15/tab2pc2.html#17

Overview
Without taking wind into consideration, a CCW direction will almost certainly be more favorable. If there is a South wind, CCW will certainly be preferred since the East side of the island is more exposed to the wind and it will be a downwind leg. Racers may wish to consider a CW direction if there is a strong North wind. This would take advantage of a downwind leg on the East side of the island, but racers would face opposing the tidal currents.

Counter-Clockwise
With a 9:30 a.m. start time, racers will enter the Passage at around 9:50 a.m. They will face a 1 kt ebb tide at the North end, at the same time there is 2 kt ebb at the South end. The current will be decreasing rapidly so the trip through the Passage should get easier rather than more difficult. During the leg along the West side of the Island, there will be a transition from a weak ebb at the N end to a weak flood towards the S end. Earlier arrivals at Rich Passage will take better advantage of the weak .5 to 1 kt ebb, since it weakens fairly rapidly and goes slack at 11:29 a.m. to noon.

Clockwise
This is less favorable than counter-clockwise. Racers headed South on the East side of Bainbridge will be facing a weak ebb tide. Rich Passage goes slack at 11:29 a.m. to noon – earlier arrivals will also face a weak ebb through the Passage. A greater problem occurs approaching Agate Passage, where the flood will be increasing rapidly and peaking at 4.2 kt at 2:10 p.m. Racers will typically be facing a 3 kt or greater flood. The earlier arrival the better.

Tidal Currents
Agate Passage N End - Flood Direction, 230 True, Ebb (-) Direction, 032 True
Max Current -2 kt (ebb) at 7:44 a.m.
Slack Water 10:45 a.m.
Max Current +1.7 kt 2:03 p.m.

Agate Passage S End - Flood Direction, 216 True, Ebb (-) Direction, 037 True
Max Current -3.9 kt (ebb) at 7:56 a.m.
Slack Water 10:48 p.m.
Max Current 4.2 kt (flood) 2:10 p.m.

Rich Passage W End - Flood Direction, 238 True. Ebb (-) Direction, 055 True
Max Current -3.4 kt (ebb) at 9:05 a.m.
Slack Water 11:29 a.m.
Max Current +3.2 kt (flood) at 2:55 p.m.

Rich Passage Off Pleasant Beach
Max Current  -3.1 kt (ebb) at 9:26 a.m.
Slack Water 11:59 a.m.
Max Current 1.7 kt (flood) at 2:48 p.m.







Steve Bennett
 

Thanks Tom, for a more thorough analysis than you would have gotten from me.   I totally concur with your call.  Here is my read:
If a 5 hour Marathoner took the counter-clockwise route, she would face almost no current at the Agate Pass Bridge with the Slack occurring at 10:47. At Point White, about half-way, she would have a supporting current of 1.5 kt, building through the pass.

If however, she opted for the clockwise route, she  would be fighting that same 1.5 kt current when she hit Point White, and facing an uphill 4 kt current at the Agate Pass Bridge.  Not a big choice this year.
Look forward to seeing you all on Saturday.  We'll have the usual soup and bread at the finish, also a nice selection of commemorative hats, thanks to Stoneway Concrete.

Tide charts attached, I think.

Steve


From: "tkreyche@... [SoundRowers]" To: SoundRowers@...
Sent: Monday, September 7, 2015 6:10 PM
Subject: [SoundRowers] Bainbridge Currents for Sept 12, 2015

 
Here's my take on the tidal currents for next Saturday's race. I'm interested to hear other opinions.

...Tom Kreyche

Sources
http://www.deepzoom.com/index.html
https://tidesandcurrents.noaa.gov/currents15/tab2pc2.html#17

Overview
Without taking wind into consideration, a CCW direction will almost certainly be more favorable. If there is a South wind, CCW will certainly be preferred since the East side of the island is more exposed to the wind and it will be a downwind leg. Racers may wish to consider a CW direction if there is a strong North wind. This would take advantage of a downwind leg on the East side of the island, but racers would face opposing the tidal currents.

Counter-Clockwise
With a 9:30 a.m. start time, racers will enter the Passage at around 9:50 a.m. They will face a 1 kt ebb tide at the North end, at the same time there is 2 kt ebb at the South end. The current will be decreasing rapidly so the trip through the Passage should get easier rather than more difficult. During the leg along the West side of the Island, there will be a transition from a weak ebb at the N end to a weak flood towards the S end. Earlier arrivals at Rich Passage will take better advantage of the weak .5 to 1 kt ebb, since it weakens fairly rapidly and goes slack at 11:29 a.m. to noon.

Clockwise
This is less favorable than counter-clockwise. Racers headed South on the East side of Bainbridge will be facing a weak ebb tide. Rich Passage goes slack at 11:29 a.m. to noon – earlier arrivals will also face a weak ebb through the Passage. A greater problem occurs approaching Agate Passage, where the flood will be increasing rapidly and peaking at 4.2 kt at 2:10 p.m. Racers will typically be facing a 3 kt or greater flood. The earlier arrival the better.

Tidal Currents
Agate Passage N End - Flood Direction, 230 True, Ebb (-) Direction, 032 True
Max Current -2 kt (ebb) at 7:44 a.m.
Slack Water 10:45 a.m.
Max Current +1.7 kt 2:03 p.m.

Agate Passage S End - Flood Direction, 216 True, Ebb (-) Direction, 037 True
Max Current -3.9 kt (ebb) at 7:56 a.m.
Slack Water 10:48 p.m.
Max Current 4.2 kt (flood) 2:10 p.m.

Rich Passage W End - Flood Direction, 238 True. Ebb (-) Direction, 055 True
Max Current -3.4 kt (ebb) at 9:05 a.m.
Slack Water 11:29 a.m.
Max Current +3.2 kt (flood) at 2:55 p.m.

Rich Passage Off Pleasant Beach
Max Current  -3.1 kt (ebb) at 9:26 a.m.
Slack Water 11:59 a.m.
Max Current 1.7 kt (flood) at 2:48 p.m.





Debbie Natelson
 

Thanks Tom!  Great analysis.  So nice of you to share.  I have a sched conflict and may not be able to make this years Bainbridge race :( -- but have a great one all who do get to do one of my favorite races.  Always a challenge, no matter which way you go. 

Debbie

On Mon, Sep 7, 2015 at 6:10 PM, tkreyche@... [SoundRowers] <SoundRowers-noreply@...> wrote:
 

Here's my take on the tidal currents for next Saturday's race. I'm interested to hear other opinions.


...Tom Kreyche


Sources
http://www.deepzoom.com/index.html
https://tidesandcurrents.noaa.gov/currents15/tab2pc2.html#17


Overview

Without taking wind into consideration, a CCW direction will almost certainly be more favorable. If there is a South wind, CCW will certainly be preferred since the East side of the island is more exposed to the wind and it will be a downwind leg. Racers may wish to consider a CW direction if there is a strong North wind. This would take advantage of a downwind leg on the East side of the island, but racers would face opposing the tidal currents.


Counter-Clockwise

With a 9:30 a.m. start time, racers will enter the Passage at around 9:50 a.m. They will face a 1 kt ebb tide at the North end, at the same time there is 2 kt ebb at the South end. The current will be decreasing rapidly so the trip through the Passage should get easier rather than more difficult. During the leg along the West side of the Island, there will be a transition from a weak ebb at the N end to a weak flood towards the S end. Earlier arrivals at Rich Passage will take better advantage of the weak .5 to 1 kt ebb, since it weakens fairly rapidly and goes slack at 11:29 a.m. to noon.


Clockwise

This is less favorable than counter-clockwise. Racers headed South on the East side of Bainbridge will be facing a weak ebb tide. Rich Passage goes slack at 11:29 a.m. to noon – earlier arrivals will also face a weak ebb through the Passage. A greater problem occurs approaching Agate Passage, where the flood will be increasing rapidly and peaking at 4.2 kt at 2:10 p.m. Racers will typically be facing a 3 kt or greater flood. The earlier arrival the better.


Tidal Currents
Agate Passage N End - Flood Direction, 230 True, Ebb (-) Direction, 032 True

Max Current -2 kt (ebb) at 7:44 a.m.

Slack Water 10:45 a.m.

Max Current +1.7 kt 2:03 p.m.


Agate Passage S End - Flood Direction, 216 True, Ebb (-) Direction, 037 True

Max Current -3.9 kt (ebb) at 7:56 a.m.

Slack Water 10:48 p.m.

Max Current 4.2 kt (flood) 2:10 p.m.


Rich Passage W End - Flood Direction, 238 True. Ebb (-) Direction, 055 True

Max Current -3.4 kt (ebb) at 9:05 a.m.

Slack Water 11:29 a.m.

Max Current +3.2 kt (flood) at 2:55 p.m.


Rich Passage Off Pleasant Beach

Max Current  -3.1 kt (ebb) at 9:26 a.m.

Slack Water 11:59 a.m.

Max Current 1.7 kt (flood) at 2:48 p.m.





Tom Kreyche
 

Here's my take on the tidal currents for next Saturday's race. I'm interested to hear other opinions.


...Tom Kreyche


Sources
http://www.deepzoom.com/index.html
https://tidesandcurrents.noaa.gov/currents15/tab2pc2.html#17


Overview

Without taking wind into consideration, a CCW direction will almost certainly be more favorable. If there is a South wind, CCW will certainly be preferred since the East side of the island is more exposed to the wind and it will be a downwind leg. Racers may wish to consider a CW direction if there is a strong North wind. This would take advantage of a downwind leg on the East side of the island, but racers would face opposing the tidal currents.


Counter-Clockwise

With a 9:30 a.m. start time, racers will enter the Passage at around 9:50 a.m. They will face a 1 kt ebb tide at the North end, at the same time there is 2 kt ebb at the South end. The current will be decreasing rapidly so the trip through the Passage should get easier rather than more difficult. During the leg along the West side of the Island, there will be a transition from a weak ebb at the N end to a weak flood towards the S end. Earlier arrivals at Rich Passage will take better advantage of the weak .5 to 1 kt ebb, since it weakens fairly rapidly and goes slack at 11:29 a.m. to noon.


Clockwise

This is less favorable than counter-clockwise. Racers headed South on the East side of Bainbridge will be facing a weak ebb tide. Rich Passage goes slack at 11:29 a.m. to noon – earlier arrivals will also face a weak ebb through the Passage. A greater problem occurs approaching Agate Passage, where the flood will be increasing rapidly and peaking at 4.2 kt at 2:10 p.m. Racers will typically be facing a 3 kt or greater flood. The earlier arrival the better.


Tidal Currents
Agate Passage N End - Flood Direction, 230 True, Ebb (-) Direction, 032 True

Max Current -2 kt (ebb) at 7:44 a.m.

Slack Water 10:45 a.m.

Max Current +1.7 kt 2:03 p.m.


Agate Passage S End - Flood Direction, 216 True, Ebb (-) Direction, 037 True

Max Current -3.9 kt (ebb) at 7:56 a.m.

Slack Water 10:48 p.m.

Max Current 4.2 kt (flood) 2:10 p.m.


Rich Passage W End - Flood Direction, 238 True. Ebb (-) Direction, 055 True

Max Current -3.4 kt (ebb) at 9:05 a.m.

Slack Water 11:29 a.m.

Max Current +3.2 kt (flood) at 2:55 p.m.


Rich Passage Off Pleasant Beach

Max Current  -3.1 kt (ebb) at 9:26 a.m.

Slack Water 11:59 a.m.

Max Current 1.7 kt (flood) at 2:48 p.m.