General History
“…Throughout history the Sandy River has had two mouths, the upper one entering the Columbia River and the lower one. In 1931 a dike/dam was built to block the main upper (easternmost) channel, allowing all flow to enter the Columbia at the lower mouth. That is today’s Sandy River. The arms of the Sandy surround and are included in a wooded wetland with ponds, sloughs, bottomlands, woodlands, and prairies, known as the Sandy River Delta. In 1991 the U.S. Forest Service acquired approximately 1,400 acres of the Sandy River delta and began restoration. Grazing was terminated, wetlands and ponds dredged, non-native vegetation removed and native vegetation was established. Future restoration plans may include removal of the 70-plus-year-old dike/dam…”
[Columbia River Images – columbiariverimages.com]
“… The Sandy River Delta is a former pasture infested with reed canary grass, blackberry and thistle. The limited over story is native riparian species such as cottonwood and ash. The shrub and herbaceous layers are almost entirely non-native, invasive species. Native species have a difficult time naturally regenerating in the thick, competing reed canary grass, Himalayan blackberry and thistle. A system of drainage ditches installed by past owners drains water from historic wetlands. The original channel of the Sandy River was diked in the 1930’s, and the river diverted into the “Little Sandy River”. The original Sandy River channel has subsequently filled in and largely become a slough…”
[Bonneville Power Administration – Sandy River Delta Habitat Restoration Project, 2001 Annual Report”]
“… The Sandy River Delta was formed by mudflows originating on Mount Hood and flowing down the Sandy River to the Columbia. The most recent of these mudflows was about the year 1800. By 1900, the delta had been reworked by floods on the Columbia, as well as a constant stream of sediment coming down the Sandy River as the river cleared its channel. The larger part of the river flowed under the railroad and highway bridges and about a half mile north. At that point, it veered east and entered the Columbia River almost two miles east of where it does today. A secondary, smaller channel existed where today’s current channel exists. In 1904, a large flood partially blocked the secondary channel and it began to run dry during the fish runs. In an effort to help fish runs, a dam was built in 1931 that completely blocked the main eastern channel. In this way the river was forced in its entirety into the former secondary channel. The original dam was a 750 foot wide, five foot high barrier constructed of piling. In 1938, the dam was improved to a 10 foot high structure filled with riprap. In time, continuing erosion filled the old river channel with sediment. Today the dam is nearly buried in sediment and only the top is visible, used as a road by power line maintainers and a trail by the rest of us….”
[Portland Hikers Field Guide – http://www.portlandhikersfieldguide.org]
Excerpt: The Journals of Lewis & Clark
Clark, November 3, 1805 …
The Fog So thick this morning that we could not See a man 50 Steps off, this fog detained us untill 10 oClock at which time we Set out, accompanied by our Indian friends who are from a village near the great falls, previous to our Setting out Collins killed a large Buck, and Labiech killed 3 Geese flying. I walked on the Sand beech Lard. Side, opposit the canoes as they passed allong. The under groth rushes, vines &c. in the bottoms too thick to pass through, at 3 miles I arrived at the enterance of a river which appeared to Scatter over a Sand bar, the bottom of which I could See quite across and did not appear to be 4 Inches deep in any part; I attempted to wade this Stream and to my astonishment found the bottom a quick Sand, and impassable— I called to the Canoes to put to Shore, I got into the Canoe and landed below the mouth, & Capt Lewis and my Self walked up this river about 1½ miles to examine this river which we found to be a verry Considerable Stream Dischargeing its waters through 2 Chanels which forms an Island of about 3 miles in length on the river and 1½ miles wide, composed of Corse Sand which is thrown out of this quick Sand river Compressing the waters of the Columbia and throwing the whole Current of its waters against its Northern banks, within a Chanel of ½ a mile wide, Several Small Islands 1 mile up this river, This Stream has much the appearance of the River Platt: roleing its quick Sands into the bottoms with great velocity after which it is divided into 2 Chanels by a large Sand bar before mentioned, the narrowest part of this River is 120 yards—on the Opposit Side of the Columbia a ?large Creek? [NB: Small river called Seal river] falls in above this Creek on the Same Side is a Small prarie. extensive low country on each Side thickly timbered.
The Quick Sand river appears to pass through the low countrey at the foot of those high range of mountains in a Southerly direction,— The large Creeks which fall into the Columbia on the Stard. Side rise in the Same range of mountains to the N. N. E. and pass through Some ridgey land— A Mountain which we Suppose to be Mt. Hood is S. 85° E about 47 miles distant from the mouth of quick sand river This mtn. is Covered with Snow and in the range of mountains which we have passed through and is of a Conical form but rugid— after takeing dinner at the mouth of this river we proceeded on passed the head of a Island near the lard Side back of which on the Same Side and near the head a large Creek falls in, and nearly opposit & 3 miles below the upper mouth of quick Sand river is the lower mouth, [for?] This Island is 3½ miles long, has rocks at the upper point, Some timber on the borders of this Island in the middle open and ponney [NB: pondy]. Some rugid rocks in the middle of the Stream opposit this Island. ?proceeded in? [NB: proceeded on] to Center of a large Island in the middle of the river which we call Dimond Isld. from its appearance, here we met 15 Indn men in 2 canoes from below, they informed us they Saw 3 vestles below &c. &c. we landed on the North Side of this Dimond Island and Encamped, [6] Capt. L walked out with his gun on the Island, Sent out hunters & fowlers— below quick Sand River the Countrey is low rich and thickly timbered on each Side of the river, the Islands open & Some ponds river wide and emence numbers of fowls flying in every direction Such as Swan, geese, Brants, Cranes, Stalks [NB: Storks], white guls, comerants & plevers &c. [7] also great numbers of Sea Otter in the river— [8] a Canoe arrived from the village below the last rapid with a man his wife and 3 children, and a woman whome had been taken prisoner from the Snake Inds. [NB: on a river from the South which we found to be Mulknoma] on Clarks River [9] I Sent the Interpreters wife who is a So So ne or Snake Indian of the Missouri, to Speake to this Squar, they Could not understand each other Sufficiently to Converse. This familey and the Inds. we met from below continued with us Capt Lewis borrowed a Small Canoe of those Indians & 4 men took her across to a Small lake in the Isld. Cap L. and 3 men Set out after night in this Canoe in Serch of the Swans, Brants Ducks &c. &c. which appeared in great numbers in the Lake, he Killed a Swan and Several Ducks which made our number of fowls this evening 3 Swan, 8 brant and 5 Ducks, on which we made a Sumptious Supper. We gave the Indian—who lent the Canoe a brant, and Some meat to the others. one of those Indians, the man from the village near the lower Rapids has a gun with a brass barrel & Cock of which he prises highly— note the mountain we Saw from near the forks proves to be Mount Hood