Water Sampling from my Sea Kayak

posted Aug 25, 2014, 8:40 AM by Richard Sevenich   [ updated Aug 25, 2014, 9:04 AM ]
The Lake Pend Oreille Waterkeeper is a non profit organization whose main focus is the health of Lake Pend Oreille in North Idaho. Among its myriad activities is a Water Quality Monitoring Program which depends on local volunteers to gather lake water samples on the 3rd Tuesday of five months, June through October. My schedule allowed me to volunteer for those months in 2014. Sampling is rescheduled if the weather is rough or rainy, because in both cases it is difficult to measure the turbidity of the water and establish a desired sampling depth. My sampling site assignment was a point in the Pend Oreille River off Tank Hill in the nearby community of Dover. [ I rather nastily refer to Tank Hill (with its scattering of new, LARGE houses) as Cape Ostentatia. Some might say that this indicates envy.] I chose to use my sea kayak for this sampling activity, a 2003 Boreal Design Ellesmere. Her name is Bianca.

Adding an Outrigger to my Kayak

Bianca is 17 feet long with a beam of 22 inches. Although this is quite ideal for sea kayaking, it is much less so for water sampling, where one must lower moderately heavy objects such as a Secchi disk or a largish water sampling apparatus over the side. Obviously, the water sampling activity compromises the stability of the kayak. This note details simple temporary modifications which significantly enhance the kayak's calm water stability by adding a home-made outrigger.

[Note: Kayak stability is an interesting topic by itself. In fact, in very rough water with an expert paddler, this kayak would be much more stable without the outrigger. However, water sampling is done in relatively calm water where the outrigger adds stability for the sampling tasks. For example, in deploying the Secchi disk to assess turbidity, the kayaker must lower the somewhat heavy disk over the boat's side and lean out far enough to view the disk as it descends, say, 30 feet. For stability it is preferable to edge a kayak rather than lean, but this is not practical here.]

The core of the modification is to jury rig a double outrigger, converting the boat from a kayak to a trimaran. What gear did I need for this modification?
  • an extra paddle (I carry one any way)
  • two paddle floats ( I already carry one)
  • two straps (of the sort used to attach boats to roof racks)
Of course, I must also carry the water sampling kit. To hold the kit items, I purchased a bag from a local Army Surplus store, choosing one which provided a way to attach it to my deck rigging while also having an opening easily accessible from the cockpit.

The First Attempt

The longer strap (red in subsequent photos) is about 9 feet long. It is doubled and buckled to itself. It is then passed under the kayak and used to attach the spare paddle to the deck as shown in the first two photos below.




Next the two paddle floats are attached to the ends of that paddle resulting in a double outrigger providing the desired stability:
This was a workable first attempt. The outrigger was placed far enough forward on the deck so I could paddle the 2.5 miles out to the sampling site with the outrigger already deployed. However, the kayak is awkward to paddle with the outrigger in place. Even in calm water, the outrigger would dig in now and then, making the kayak swerve.

The Second and Final (Successful) Attempt

In the next attempt, I moved the outrigger to a position just in front of the cockpit so it could be deployed after I had paddled the 2.5 miles to the sampling site. Obviously, passing the red strap under the kayak would not be feasible once on the water. The solution was to attach the strap to the kayak before launching, using the shorter blue strap to hold it in place as shown below.

 
Once at the sampling site, the outrigger would be assembled as shown in the final two photos:


The final photo above shows that I also replaced the 'working side' paddle float with the more buoyant inflatable style (yellow).

A question remains, “How does one assemble the outrigger once at the sampling site?”. The following items must be within reach:
  • the two piece spare paddle
  • the two paddle floats
The subsequent assembly process is as follows:
  • inflate the first paddle float and attach it to the blade of one part of the paddle
  • insert the non-blade end through the red strap loop on the right side of the kayak (loosen the red and blue straps as necessary)
  • attach the second paddle float to the blade of the other part of the paddle
  • insert the non-blade end through the red strap loop on the left side of the kayak (loosen the red and blue straps as necessary)
  • join the two parts of the two piece paddle to make the single paddle
  • tighten the red and blue straps so that the outrigger is firmly in place
Caution: Never completely unbuckle the straps during the process above.

Miscellaneous

Do I really need a double outrigger; wouldn't an outrigger just on the sampling side be adequate? Yes, a single outrigger would likely do - as long as I don't get clumsy and accidentally lean the wrong way while struggling with the assortment of sampling gear. So, my choice is the conservative double outrigger.

I could use only my primary paddle for this job and not even bring the spare, but the primary paddle provides a way to maneuver a bit, once the outrigger is in place. Further, I attach a leash to my primary paddle, so I can lay it in the water along the non-sampling side the boat to keep it out of the way while sampling – yet it remains readily available.

I removed the drip rings from the spare paddle, because they just get in the way when assembling or disassembling the outrigger.

My kayak has a day hatch, reachable from the cockpit. Before launch I put several ice packs in the hatch, creating a cooler. Once on the water, I can place samples in this cooler when appropriate, thereby preserving them for the 2.5 mile paddle home.

Once the sampling activity is done and the samples stored, I disassemble the outrigger, stowing its various parts. Although not really necessary, I also remove the red and blue straps and stash them in the kayak for the return trip.

The bag I purchased from Army Surplus (to hold the water sampling kit) was chosen from the usual motley selection available at such stores. There wasn't another exactly like it, but there were others that would have worked as well. It is not waterproof, but it is ugly. Shopping at Army Surplus stores is every boy's dream.
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