Oregon Coastal Salmon Restoration Initiative

Issue Background:

Water quality is important to salmonid survival. Water quality is usually thought of in terms of the water quality standards the state has adopted under the federal Clean Water Act (CWA) (33 U.S.C. 466 et seq.). Under Section 303(c)(2)of the CWA, water quality standards are comprised of the designated beneficial uses to be protected and narrative or numeric criteria that are designed to prevent impairment of the beneficial uses. Oregon has designated anadromous fish passage, salmonid fish spawning and rearing, and resident fish and aquatic life as beneficial uses to be protected in coastal basins (OAR Chapter 340, Division 41). To protect these and other beneficial uses, Oregon has also adopted specific numeric and narrative criteria that address thermal conditions (temperature), chemical parameters (e.g., dissolved oxygen, pH, toxic substances), physical conditions (e.g., sedimentation), biological conditions, and nondegradation of high quality waters (OAR Chapter 340, Division 41). All of these standards work together to provide the thermal, chemical, physical and biological conditions salmonids and other aquatic life require to survive and thrive in coastal waterbodies.

It is important to recognize that the primary objective of water quality standards is protection of the designated beneficial uses. All aquatic life requires a set of physical, chemical, thermal and biological conditions that are appropriate to their life cycles. This means a properly functioning aquatic ecosystem is necessary to avoid impairment of beneficial uses. If Oregon's water quality standards don't provide the necessary level of protection, they need to be revised to address the problem. Under Section 303(c)(1) of the CWA, Oregon is required to review and update as necessary its water quality standards at least once every three years. The requirement to protect beneficial uses also means that physical habitat elements such as riparian vegetation, channel morphology, and stream flows play an important role in meeting Oregon's water quality standards and as such must be protected and restored as necessary to avoid beneficial use impairment.

Water quality conditions in coastal waterbodies have been monitored and analyzed by DEQ and others for many years. DEQ has recently gathered and analyzed all readily available information on coastal water quality during the preparation of its 1994/96 303(d) list of water quality limited waterbodies. A summary of the results of that effort is provided in Table 1. There are approximately 18,137 miles of streams in the coastal basins. Of that number, 6,086 stream miles (33.5%) have been assessed by DEQ using available water quality information. Of the 6,086 stream miles assessed, 3,035 stream miles (49.9%) were found to be water quality limited, and 2,345 stream miles (38.5%) need additional data or were of potential concern. Only 706 stream miles (11.6%) of those assessed were found to be meeting all state water quality standards. It is clear from this information that water quality is a significant factor that needs to be addressed in order to halt the decline and achieve restoration of coastal salmonid populations.

Background on Factors for Decline:

The water quality related factors that have caused the decline of salmonids in coastal basins have been identified based upon water quality monitoring data and the professional judgment of state agency staff of the conditions in coastal waterbodies that are impairing salmonids. Also, the recommendations of the Botkin and National Research Council (NRC) Reports were considered in identifying factors for decline.

Not all identified factors for decline are of equal weight in contributing to the decline of coastal salmonids. A review of the parameters listed in Table 1 from left to right across the columns follows:

Aquatic Weeds:
Nuisance aquatic weeds may be considered a problem in coastal lakes in some situations, based on impacts to recreation and to salmonid production. Dense weeds may indicate a problem with excess enrichment, they provide cover for predatious exotic fish, they may contribute to decreased oxygen concentrations during periods of decomposition, and they may alter the planktonic food chain.

Biological Criteria:
Biological criteria is a state water quality standard that relates to the overall health of biological communities in stream reaches. The biological condition of a stream is measured by sampling specific aquatic communities and determining if they are healthy, or show signs of impairment compared with representative undisturbed streams. A variety of aquatic communities can be measured to evaluate biological condition. Benthic macroinvertebrate and fish assemblages are the most common aquatic communities sampled for assessing the biological condition of streams.

In recent years DEQ has undertaken several studies to determine the current status of conditions in coastal streams. In 1992 and 1993, 36 reference sites were sampled to determine the biological condition at undisturbed stream sites. Between 1994 and 1995, 57 randomly selected stream sites in the Oregon coast range were sampled for chemistry, habitat, macroinvertebrates and fish assemblages. This sampling was funded by EPA's REMAP program.

The REMAP project sampled first through third order (wadable) coastal streams at randomly located sites throughout the Coast Range. Because sites were randomly selected the results can be used as an estimate of the general status of first through third order coastal streams. While 57 sites is a minimal number of data points for estimating the overall status of coastal streams, it is the best data set currently available to evaluate the current status of streams. With additional funding, DEQ is proposing to sample 150 random sites on a five-year rotating cycle (30 sites per year; sites re-sampled every five years).

Preliminary results of the benthic macroinvertebrate data from the REMAP study have been used to estimate the current status of biological conditions in coastal streams. The invertebrate assemblage from each site was assessed using a set of "biometrics" which are based on diversity, trophic structure and pollution sensitivity of specific species. The metrics are scored, and a total "bio score" is calculated for each site. This score represents the biological condition of the stream based on the macroinvertebrate community. The percent frequency chart below shows the range of total metric scores for the REMAP sites.

Total scores ranged from 10 to 46. Based on these results and reference site data:

• scores from 35 to 46 represent undisturbed communities,
• scores from 25 to 35 indicate some disturbance, and
• scores less than 25 indicate more severe disturbance or impairment.

Based on scores less than 25, one would estimate that 35 percent of first through third order coastal streams are impaired. This is a rough estimate, but it is DEQ's best estimate of the current status of biological condition in wadable coastal streams. Fish assemblage results are also being analyzed and will be used to calculate similar