I'm interested in diving the Oregon Coast, but after a bit of research a lot of the dives seem to need some pretty good conditions to be able to dive them. I found the Stonewall Banks Buoy (20 nautical miles west of Newport) and it seems like probably a good one to use for dive planning.
So, what I'm needing help with is this:
What are GOOD conditions? What are GREAT conditions? What are lousy conditions? What do I need to pay particular attention to? (ie: wave height, average or dominant wave period?)
I am soooo confused!
Before I make the 2-3 hour drive out there, I want to know if it's gonna be good or not.
And is this the buoy you'd use to plan a dive at Tillamook Bay or Netarts, or should you use a different one?
- Janna
Janna Nichols My underwater photo galleries REEF Citizen Science Program Manager
Seen any cool critters lately?
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I can give you a general primer from a predicting the surf standpoint. Buoys will give you three relevant pieces of information, direction, wave height and wave period.
Direction is where it is coming from, obviously, and if it is a swell (an organized train of waves) the coastal features will determine whether the swell is hitting a particular area. Wintertime sees waves from the west or north, so a headland that shelters something from the north will shelter an area from a northerly swell. Summertime is southerly swells (from the storms in the southern hemisphere) so the opposite is the case. Swells are generated by storms blowing over the ocean surface for a period of time, the waves radiate out from the storm and organize (train) as they go. This is why you can have big waves on sunny, calm days (optimum surfing conditions). I'll focus on that because if the buoy says it is uber windy and the data indicates disorganized seas, then it probably is an obvious don't dive day.
In terms of wave height and period, there are a couple relationships to keep in mind. First is that longer periods (measured in seconds) equal more organized swells, which have more energy, and will equal bigger breaking waves on shore. A decent swell is in the 14-20 second range, monster swells are 20 plus. As a well-organized swell approaches, you'll see the long period waves first, then the meat of the swell will be a few seconds less. I've surfed epic swells in California in the 25 foot/25 second range that produced 40-50 foot waves on the coastline (measured from trough to crest).
Wave height must be read in conjunction with wave period. You can get decent swells that produce big surf but only have 4-6 foot heights in the open ocean (and relatively long periods-that is where the energy is). Likewise, a disorganized sea will have 6 to 12 foot wave heights and a short period (less than 12 seconds) indicating these waves are locally generated (which will be corroborated by the wind data at the buoy).
Oregon coastal diving seems to be fairly dicey in the winter to begin with. You can have surf pick up quickly, like in the middle of the dive, so you need to look offshore and see what is coming. Some of the surf forecast services can be a good resource there. I've literally seen the buoys pick up and have paddled out to flat seas in California, only to get out of the water with 10-12 foot surf all around me. Doing that in dive gear would not be fun.
Anyways, that is my brain dump on buoys, having spent the majority of my first 28 years glued to buoy reports. I'm sure the Oregon coastal divers will have more info.
One general guideline for diving with swells is that you don't want the height (in ft) to exceed the period (time). This would be for offshore sites, not beach sites. Those are what buoys are measuring and unfortunately they don't necessarily relate well to the breaking wave issue at a specific shore site. You'll need to know the sites down there and which buoy relates best. The MoCal folks have this stuff down to a science, not sure if the same types of local knowledge are widespread in the OR dive community.
Sorry - nothing useful to add regarding buoy data. I want to ask a vaguely related question... what is Stonewall Bank like? Anyone got a dive report or photos to share? I have to think it might be absolutely amazing.
“When one tugs at a single thing in nature, he finds it attached to the rest of the world.” -- John Muir
It's a Yelloweye Rockfish Conservation Area (YRCA)
"Within the Stonewall Bank YRCA it is UNLAWFUL to fish for, take or retain lingcod, Pacific halibut, flatfish, rockfish, greenling, cabezon, skates, and other marine fish species falling under the Marine Fish bag limit of 6 as of Jan. 1, 2008.
It is unlawful to fish for or take and retain any species while possessing on board any species not allowed to be taken in the area.
The YRCA, located approx. 15 miles west of Newport, consists of the high-relief area of Stonewall Bank (also known as the "Rock Pile") defined by the waypoints listed on the adjacent map. "
- Janna
Janna Nichols My underwater photo galleries REEF Citizen Science Program Manager
Seen any cool critters lately?
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Am I to look at Dominant Wave Period or Average Wave Period? They are quite different it would seem.
Thanks for all your help so far! Keep the ideas coming...
- Janna
Dominant is usually going to be the underlying swell. If the average is significantly different from it, that means there is a wind swell on top of it, which makes sense given the ~20 knot winds reported at the buoy.
What we have here (for today, a dominant period of 11 seconds and an average of 7 seconds) is a small swell with a fairly significant wind chop on top of it.
For a shore dive site you are mostly concerned with dominant. For a boat dive on a bank or pinnacle you want a balance between height+period of dominant. For local wind driven waves 15knots is a reasonable max. You can still dive in 20kn but if its already blowing 20 you probably want to skip diving cause if it picks up to 25 its starting to get dangerous (for divers nevermind the boat).
Sounder wrote:Under normal circumstances, I would never tell another man how to shave his balls... but this device should not be kept secret.
whatevah wrote:Sorry - nothing useful to add regarding buoy data. I want to ask a vaguely related question... what is Stonewall Bank like? Anyone got a dive report or photos to share? I have to think it might be absolutely amazing.
No doubt it would be amazing, but it is also deep, most of it is beyond rec depths. There are some stuff a lot closer that should be great diving. I'm thinking Johnson Rock off Ona Beach. The top of the rock is about 30 fsw and it's sitting in about 10 or 12 fathoms, not 50 fthms like Stonewall.
I've been meaning to post some of the research (ok rumors, really) I've gathered about Oregon coast dive sites. I'll do that this week.
OreCoastDiver wrote:
I've been meaning to post some of the research (ok rumors, really) I've gathered about Oregon coast dive sites. I'll do that this week.
Please do, an Oregon coast trip might be a fun one next summer.
whatevah wrote:Sorry - nothing useful to add regarding buoy data. I want to ask a vaguely related question... what is Stonewall Bank like? Anyone got a dive report or photos to share? I have to think it might be absolutely amazing.
No doubt it would be amazing, but it is also deep, most of it is beyond rec depths. There are some stuff a lot closer that should be great diving. I'm thinking Johnson Rock off Ona Beach. The top of the rock is about 30 fsw and it's sitting in about 10 or 12 fathoms, not 50 fthms like Stonewall.
I've been meaning to post some of the research (ok rumors, really) I've gathered about Oregon coast dive sites. I'll do that this week.
Please do - I have to think there is some great diving off the Oregon coast but there seems to be little available information. BTW - there are 13 fathom soundings for some parts of Stonewall Bank - that's well within reach for most of us to explore.
“When one tugs at a single thing in nature, he finds it attached to the rest of the world.” -- John Muir
Don't forget the depth datum in the US is mean low water. (mean lower low water in Canuck land - almost all in meters up there too). Realistically, plan on a 13 fathom sounding being a ~90ft dive or deeper depending on how isolated it is.
Sounder wrote:Under normal circumstances, I would never tell another man how to shave his balls... but this device should not be kept secret.
One of the things I tried to figure out this summer is if there is a correlation between drops in water temp. at the Stonewall Bank buoy and upwelling events on the central coast. I think there is. The reason that would be useful is because at the front end of those events, like the first 48 hours, there is good visibility as the clear, colder nutrient-rich waters well up from the deep. After a day or two, the visibility gets really bad because the nutrients cause an algae bloom.
So, the water temp., as measured at Stonewall Banks, would be a steady 52 and suddenly drop to 48. The water would be blue and fairly clear for a day or two and then turn to brown grunge. If there was a buoy closer to shore it would be a better indicator of the upwelling events. These events occur during the summer when the NW wind machine gets going.
CaptnJack wrote:Don't forget the depth datum in the US is mean low water. (mean lower low water in Canuck land - almost all in meters up there too). Realistically, plan on a 13 fathom sounding being a ~90ft dive or deeper depending on how isolated it is.
I hadn't forgotten. I would love to dive it sometime but it is hard to justify the trip when the OCNMS is so much closer. Maybe we'll hear more about Oregon Coast sites that could be bundled into a worthwhile trip. Looking at the charts doesn't show me much unfortunately. I have to think there are a bunch of interesting pinnacles to explore but they're not marked - at least not at the scale I have available.
“When one tugs at a single thing in nature, he finds it attached to the rest of the world.” -- John Muir
dang wish there was a couple of bouy's a lil closer inshore to the northen OR coast, the two closest seem to be NDBC station 46029 wich is 78 NM SSW of Aberdeen WA http://www.ndbc.noaa.gov/station_page.p ... n=46029and NDBC station 46089 84 NM WNW of Tillmook http://www.ndbc.noaa.gov/station_page.php?station=46089. So for diving say three arch rocks or out of Pacific City wich would be the better bouy to go off of, station 46089 out of Tillmook or station 46050 out of Newport but closer to shore ?
