Cathlapotle Submerged Cultural Resources Survey

Mud and Weeds in the Shallows

2008-08-21T08:17:00.000-07:00

On August 3rd we returned to Ridgefield, this time to examine Carty Lake, and perhaps to do some SCUBA diving. The water levels do lower during the summer months, and Carty Lake was only about three feet deep. This seemed rather low for SCUBA diving. Plus, the lake was chock full of plant life, creating a dense underwater forest that would make diving even more difficult. The wapato plants (Sagittaria latifolia) were finally visible with their arrow-shaped leaves poking out of the water. Wapato grows in lakes and ponds, and produces a small potato-like bulb that was prized by Natives along the lower Columbia. Captain William Clark (of Lewis and Clark fame) described Carty Lake and wapato collection when he visited in 1806:

"...in this pond the nativs inform us they Collect great quantities of p[w]appato, which the womin collect by getting into the water, Sometimes to their necks holding a Small canoe and with their feet loosen the wappato or bulb of the root from the bottom from the Fibers, and it imedeately rises to the top of the water, they Collect & throw them into the Canoe, those deep roots are the largest and best roots."

Wapato, however, was not a real problem for diving. It was two other plant species that dominated Carty Lake at this time of year. A sample of the two species are shown below.

After some time we decided to head over to Blackwater Lake. The last time we were there (about a month earlier) the water level was about six feet deep. Perhaps this might be a better place to SCUBA dive, or so we thought.

To our great surprise Blackwater Lake was only a foot deep, having lost five feet of water over the previous month. Not only was the water level low, the lake bottom was a soft squishy mud nearly three feet deep. Below is an image of Chuck exploring the muddy depths equipped with waders and a poking stick amidst the wapato.

If Carty Lake was too shallow for SCUBA diving, then Blackwater Lake was even worse. But, we had rented the SCUBA gear, and it would have been a pain to return to Carty Lake to dive there, so Cameron decided to SCUBA dive in one foot of water in Blackwater Lake. It was a rather hilarious and pathetic-looking "dive" in such shallow water, but it was no fault of Cameron's. He tried his best in what amounted to a shallow, muddy, weed-choked swamp. Below is an image of Cameron "diving" in SCUBA gear in Blackwater Lake.

Our hope is that conditions will be better in the Autumn when water levels are higher and the weeds die down.

---Chuck

Island Anomaly Solved?

2008-07-13T12:46:00.000-07:00

After looking at even more maps I've come to a reasonable solution for why an island appears at the end of Gee Creek in one of the maps as well as an explanation for the "mystery" island in Blackwater Lake. [See post below for my initial quandary].

My conclusion is that when the water level is very high an island is created at the mouth of Gee Creek. In fact, this island is called Squaw Island according to a map from the Washington State Department of Ecology. And this same map also shows the "mystery" Island in Blackwater Lake, as did the Clark County map. [click image to enlarge].

The island that I thought was submerged in Blackwater Lake is not submerged at all. Rather, the water level was not quite high enough in the lake to create the island, and thus it appeared to us as part of the stable land mass. If the water level were higher, this land mass would have been cut off from the lake shore, and we'd have seen this "mystery' island in Blackwater Lake. The satellite map below shows the "mystery" island when the water levels are lower, and it's not a true island. [click image to enlarge].

When we did a cursory examination in March 2008 the water levels were much lower than they were when we visited during the past month. The water levels were so much higher recently that I had a hard time imagining them getting even higher. But on further reflection, we recently noticed high water marks on some of the vertical cliff walls along parts of Gee Creek. Some of these high water marks were a few feet higher than the water level of the Creek itself.

So, I think the anomaly has been solved thanks to more maps, a bit of thinking, and good jolt of memory. Simply put, the water levels can rise much higher than we imagined, creating both Squaw Island at the mouth of Gee Creek, and the "mystery" Island in Blackwater lake. But truth be to tell, I'd still like a closer look at Squaw Island because, as the saying goes, seeing is believing.

--Chuck Sullivan

A Gee Creek Anomaly

2008-07-12T19:38:00.000-07:00

On 6 July 2008 we paddled the canoe down Gee Creek to the Columbia River. The Creek itself is a winding, meandering stream, and at this time of year it’s about 30-40 feet wide, and is strewn with fallen trees, making navigation a bit tricky. Arriving at the Columbia river came as a surprise since it’s hidden from view by trees, and it’s not until Gee Creek takes a final sharp turn to the left that the mighty Columbia springs into view. Here the river is over half a mile wide. It was hard to resist the temptation to paddle out into the Columbia if only for 100 feet or so, and, needless to say, we couldn’t resist the temptation.

One of the first things we noticed was the waves flowing into the mouth of Gee Creek, as though we were in the wake of ship that was passing by. But there was no ship passing by. This was a natural wake created by the river. The waves were about 5 to 6 inches high, and they continuously rolled toward us one after another. Five to six inch high waves might not sound like much, but we were three men tightly stuffed into a 14 foot canoe with our supplies and gear, and our excitement at paddling out of the mouth of the creek turned dead serious when we realized that the rules for navigating Gee Creek did not apply here. I recall Cameron saying “I think we should turn around. These kind of waves can easily capsize a canoe like this.” And turn around we did, and we quickly paddled back inside the safe harbor of Gee Creek. [click image to enlarge].

The mighty Columbia comes into view

Having looked at various maps, and having read some things about Gee Creek, I came to wonder if Gee Creek had always emptied into the Columbia River at the same place where we had encountered the waves. I found a reference to survey notes of the General Land Office based on a U.S. Geological Survey of 1853 stating that Gee Creek enters into the Lewis River. The Lewis River does meet up with the Columbia just north of the mouth of Gee Creek. In fact, the Lewis River is so close to Gee Creek that if the creek were to continue in a northerly direction for about 500 feet, then instead of emptying into the Columbia it would empty into the Lewis River.

Now my curiosity is such that I’d like to visit the mouth of Gee Creek again to see whether the elevation around the area is low enough that Gee Creek once could have entered into the Lewis River.

Consider the satellite image below. Route C is the present mouth of Gee Creek where it enters into the Columbia. Route A could be the remains of an old creek bed where Gee Creek would have emptied into the Lewis River. And Route B is perhaps another dry bed where Gee Creek once took a winding bend before spilling back into the Columbia. It may be that Gee Creek once followed Route A, but because of sediment from the Lewis river that route became blocked. Then perhaps Route B became the way for Gee Creek to evacuate its water. And perhaps over time, erosion forced Gee Creek to break through at Route C, which is clearly the most economical route for the river to take. [click image to enlarge].

It may also be that in times of high flooding Gee Creek empties through all three of these routes at once. I was led to this view by examining the map below where a small island appears that is not in the satellite image. This small island is what remains after Gee Creek empties at all three routes at once. [click image to enlarge].

I’m not sure what to make of this map since I’ve noticed an anomaly that I can’t explain. The map shows a small island just southeast of Blackwater Island, but we discovered no such island when we paddled there recently. There could be an island that is now under water due to the high water levels around Blackwater Lake. If this island exists it would only appear when water levels are low. However, the map also has an island at the mouth of Gee Creek that would only appear when the water levels are high. It wouldn’t make sense for the water level to be low in Blackwater Lake but high at the mouth of Gee Creek since these water bodies are connected. It may be that the data for the map was collected over a period of time, so that the data for Blackwater Lake was taken when water levels were low, and the data for the mouth of Gee Creek was taken when levels were high. The data for this map was plotted 15 June 2006, and the following disclaimer on the map itself might explain a lot:

Note: Information shown on this map was collected from several sources. Clark County accepts no responsibility for any inaccuracies that may be present.

Well, I guess this means that we’ll just have to return to the mouth of Gee Creek to do some thorough exploring in order to discover what no map or satellite image can reveal.

--Chuck Sullivan

Depth and Swamp Thing

2008-06-26T13:57:00.000-07:00

With all necessary permits finally in hand, we went out to Ridgefield on Saturday, June 18th. Our goals were to take depth soundings of Blackwater Lake (the location of our first underwater survey) and to simply explore. Using Todd and Jen's new MadRiver Canoe, we explored the entire lake and part of Gee Creek and took approximately 20 depth soundings. The current depth of the lake is 6 to 7 feet, and Gee Creek is 8 to 9 feet. The water is presently 3 to 4 feet higher than it would be most of the year due to the Spring flood. We can expect the depth to drop 3 to 4 feet later in the Summer.

Cameron--courageously without his wetsuit--decided to do some snorkeling around and he learned that the current visibility is a chlorophyll-y 2 to 3 feet, and at the bottom 1 foot the water turns black. And the lake bottom is a fine black muck. As can be seen in the picture to the left, Cameron had to contend with a copious amount of weeds. This does not bode well for our hopes to find submerged artifacts in this portion of the refuge. It will be a challenge SCUBA diving and snorkeling in thick weeds, and it will be an even greater challenge finding artifacts in black muck and murky water.

Gee Creek looked more promising. The water is constantly moving so hopefully the sedimentation will be less mucky and there will be an increased chance that we can spot exposed artifacts . Blackwater Lake is fairly stagnant so it is more likely that any artifacts that may be down there are buried under who-knows-how-many feet of black muck.

All Systems are Go

2008-06-09T17:06:00.000-07:00

We've finally obtained all the necessary permits. Our next trip out (perhaps this weekend) will be to do depth soundings, so we'll have some idea of the depth of the first lake we'll be exploring. This will involve paddling out in a canoe and periodically dropping a weighted rope (marked in meter increments) overboard.

We've made a map of our corner of the lake using a standard archaeological grid design, and it would seem that between 10-20 strategically placed depth soundings should give us a good indication of the lay of the lake bottom.

Equipment and Supplies

2008-03-23T14:59:00.000-07:00

We have begun to acquire the equipment and supplies we will need for the survey. Todd and his wife Jen bought a canoe this week (see below picture), which will be essential for providing surface support with SCUBA operations and for transporting us and our gear around the lakes. Chuck recently picked up some nylon rope, insect repellent and waders. Below is a list of equipment and supplies that we will continuously update.

Things we have:

Canoe (Todd/Jen)

Rope (Chuck & Cameron)

Marker flags (Chuck)

Deet (Chuck)

GPS (Cameron)

Spyglass (Cameron/Todd)

First Aid Kit (Cameron)

1 pair waders (Chuck)

4 Life jackets (Todd)

Dry bags: 1 large, 1 medium, 2 small (Todd)

Some old towels (Todd)

Underwater search lights (Todd-1 main, 1 wristmount / Cameron-1 wristmount)

Hand soap or waterless hand cleaning solution (Chuck)

Plastic bowls, plastic cups, eating utensils (Chuck)

Five gallon water container (Todd)

Inflatable raft & pump (Todd)

Video Camera (Cameron)

Digital Camera w/ underwater housing (Jen/Todd)

Printed maps, plus mapped search plan [with plastic folder] (Chuck)

Things we need:

Lightweight table with 3 small folding chairs (Todd/Chuck)

Shade canopy

Printed maps, plus mapped search plan [with plastic folder] (Chuck & Todd)

Food menu items (Chuck)

Two-way radios (Cameron)

Anchor (Todd)

Things we need to make

Video Camera Housing (Cameron)

Getting Ready

2008-03-20T08:08:00.000-07:00

Over the past few weekends we have explored some of the shore areas of the "Middle Lands" portion of the refuge, looking for places to carry out SCUBA operations and set up a work station. We found two great places to work from: one on the north end of the lake and the other on the south end. Both sites will allow relatively easy access to the water. Below is a picture of the north end of the Middle Lands lake with Cameron in the foreground, sketching the shoreline. Click image to enlarge.

And the picture below is of the south end of the lake. Cameron and Chuck are noting observations.

Below are a few pictures of some interesting rock formations my wife Jen came across. The top photo is of some boulders and rocks that appear to have been arranged by humans. A colleague of Cameron's in the Department of Anthropology at Portland State University believes the rocks could be an old hunting blind. If it is in fact a hunting blind built by humans, the question then is whether Cathlapotle people or Euro-Americans built it. More on this later. Click image to enlarge