Tillamook River Basin
 
Photograph of Upper Tillamook by Demeter Design
 

Tillamook River Watershed

The Tillamook River is the southern-most watershed in the Tillamook Bay basin. The total river length is 17 miles with a waterhsed drainage area of approximately 61 square miles (36,395 acres). The Tillamook River comes out of the low coastal hills southwest of the town of Tillamook. Most of the Tillamook River watershed is in private ownership, split between private forest, agriculture and a mix of rural and urban residential. Only 14% of the watershed is public land.

The Tillamook is the only Tillamook Bay basin not dominated by steep stream channels. Low-gradient channels account for over 30% of the drainage network in the Tillamook subbasin. The lowland floodplains are extensive and are a particularly dominant feature. The lower Tilamook basin is dominated by pasture land with some residential properties. The upper basin enters forested hills dominated by private forest lands. The lower 1 mile shares a channel with the Trask River. The geology the is comprised of sedimentary and volcanic rocks.

   Photograph of the Upper Tillamook River by Demeter Design
Photograph of Fish Ladder on Tillamook River by Demeter Design
Habitat
The Tillamook basin consists of cleared pastureland in the lowlands and forested uplands. The City of Tillamook has intake dams on both Fawcett and killam creeks which have been partial barriers. In 2005, work was completed to imrove fish passage at the Killam Creek dam in association with work to improve and raise the dam level. Enhancement projects have also been completed on Bewley Creek and Killam Creek over the past five years. The lower river is confined by a set of low levees. During high flow events, water will overtop these structures resulting in lowland flooding.
Fish Species Present
Chinook Salmon (spring/fall runs) Coho Salmon Chum Salmon Steelhead (summer/winter runs) Cutthroat Trout (resident/sea-run) Lamprey (brook/pacific) - A few sturgeon and shad use portions of the tidewater reach. A majority of the Tillamook River system has been selected as a core salmonid area. Coho salmon are found throughout the watershed, using the upper mainstem and most of the larger tributaries for spawning. - Chinook: Fall Chinook use extends into the upper mainstem for spawning and into the eastern tributary streams. Bewley creek is the only western tributary known to support spawning fall chinook in the lower reach of the stream. Juvenile chinook rear within the lower reach below the mouth of Bewley creek. Spring chinook are not commonly found to be productive in the Tillamook basin. Chum salmon distribution extends throughout much of the mainstem and lower portions of many of the tributaries. Chum have been noted through much of Bewley creek. Steelhead: Winter steelhead spawning distribution extends throughout the entire basin. Summer steelhead are not commonly found to be productive in the subbasin. Cutthroat trout are found throughout the entire subbasin as sea-run and resident populations. Other native fish species present include sculpin spp. and stickleback. Green Sturgeon can be found within the tidewater reach. Some other aquatic Species of Concern include the northern red-legged frog, Columbia torrent salamander and the tailed frog.		   Photograph of Giant Salamander by Demeter Design
Photograph of the Tillamook Rainforest by Demeter Design
Issues affecting watershed health include channelization of lowland reaches through extensive channel modifications, passage barriers, disconnection of river from floodplains and wetlands, lack of off-channel habitat for winter refuge and rearing of coho salmon and cutthroat trout, erosion, pollution, livestock impacts, lack of LWD and LWD recruitment potential, lack of channel complexity in stream channels, and degraded riparian and floodplain habitat.
Vegetation in the watershed has changed greatly since pre-settlement. Historically, vegetation included a large amount of late-successional forest, with priairies, swamps, marshes and tidally-influenced forest in the lowlands. Uplands were mostly a mix of western hemlock, western red cedar, douglas fir, grand fir, noble fir and sitka spruce. Since then land has been cleared and harvested, wetlands drained and pastures created.   Photograph of wetland in upper Tillamook River by Demeter Design
 
Water Quality
The high intensity of water use in the Tillamook subbasin may be a factor influencing water temperatures, and may be affecting patterns of bacterial contamination. The City of Tillamook operates water intake dams on Fawcett and Killam creeks. Temperatures in most tributaries exceed 70F degrees during July and August. Although winter and spring flows in most tributaries provide for the utilization of spawning and rearing areas, low summer flows limit fish production in the basin. During major flood events, flood water can cover more than 2,300 acres throughout the Tillamook lowlands. The Tillamook River was documented as the most severely contaminated river. According to the EPA the Tillamook River routinely has the highest bacteria concentrations of the five rivers. Storm-Based Monitoring has quantified bacteria loads to the bay from four main tributary rivers of the Tillamook Bay watershed. Contamination from agricultural, industrial and domestic sources, including failing septic tanks, contribute to water quality problems in the Tillamook. Focusing on corrective actions along this river would result in the most "bang for the buck" in terms of improving water quality.
 
 
503-322-0002
tbwc@oregoncoast.com
605 Garibaldi AvenueGaribaldi, OR 97118
 
Website by Demeter Design 2008