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Performed for the Van Duzen Watershed Project Funded by: Friends of Eel River &

Comments on Van Duzen River and Yager Creek Sediment TMDL with Recommendations for Implementation Action and Monitoring. Performed for the Van Duzen Watershed Project Funded by: Friends of Eel River & California State Water Resources Control Board By Patrick Higgins

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Performed for the Van Duzen Watershed Project Funded by: Friends of Eel River &

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  1. Comments on Van Duzen River and Yager Creek Sediment TMDL with Recommendations for Implementation Action and Monitoring Performed for the Van Duzen Watershed Project Funded by: Friends of Eel River & California State Water Resources Control Board By Patrick Higgins Consulting Fisheries Biologist

  2. Executive Summary • Fisheries discussions ignore extinction risk for species such as coho. • Water quality targets are scientifically derived and suitable for gauging recovery, but no systematic monitoring has followed to determine trends. • No projected trajectory for recovery of fisheries or water quality or schedule of compliance. • Upland sediment reduction strategy is insufficient and lacks discussion of prudent risk limits for watershed disturbance. • Emphasizes “past land use” practices and downplays the significance of logging-related damage since 1985. • Changes in flow caused by roads and logging is ignored despite potential for more frequent damaging floods and decreased summer base flows. • Elevated water temperature is not addressed. • A decade after the technical TMDL the State has no implementation plan.

  3. Van Duzen TMDL Sub-basins Lower Van Duzen (129 sq. mi.) : Grizzly Creek downstream to the Eel River, including tributaries and Yager Creek except for headwaters of NF, SF and MF. Very high timber harvest rates and high road densities since 1985. Middle Van Duzen (202 sq. mi.): Van Duzen from Grizzly Creek to the South Fork, the lower South Fork, and the upper North, Middle and South Forks of Yager Creek. Mélange terrain, inner gorge failures. Upper Van Duzen (92 sq. mi.): Headwaters of the mainstem Van Duzen River, upper South Fork and West Fork Van Duzen River. Mélange terrain with ranching and ranch roads.

  4. According to PWA (1999), the largest contribution of sediment from landslides in the Van Duzen River watershed is from unstable sandstone terrain, followed by active and dormant earthflows, stable mélange and stable sandstones, respectively.

  5. The Middle Van Duzen sub-basin had the highest overall sediment yield, followed by the Upper basin, but management related sediment from landslides was highest in the Lower basin. Data from PWA (1999) and the VD TMDL (EPA, 1999).

  6. Shortcomings of PWA Sediment Budget • Only 1% of the watershed sampled (3200 ac. of 275,000 ac) • No surface erosion calculated from logging roads, skid trails or temporary roads • No bank failures ascribed to cumulative effects. • While 63% of stream xings in the Lower Basin had diversion potential, no schedule or mechanism for remediation. No inventories in Middle and Upper Basins. • “Disconnecting” roads hydrologically is theoretical. Road densities, crossings and near stream roads must be reduced. • Reducing fill failures at specific locations will not solve problems due to cumulative watershed effects. • Should have recommended that all culverts be sized for 100 year flood events. Why wouldn’t you want to prevent all failures? • Calls for decreased road building on unstable slopes, but does not address logging there or put any measure in place to stop destabilizing activities.

  7. Cumulative Watershed Effects “Generally speaking, the larger the proportion of the land surface that is disturbed at any time, and the larger the proportion of the land that is sensitive to severe disturbance, the larger is the downstream impact. These land-surface and channel changes can: increase runoff, degrade water quality, and alter channel and riparian conditions to make them less favorable for a large number of species that are valued by society. The impacts are typically most severe along channels immediately downstream of land surface disturbances and at the junctions of tributaries, where the effects of disturbances on many upstream sites can interact.” Dunne et al., 2001

  8. Van Duzen Downstream of Yager Creek • Excess Sediment • Increased Peak Discharge • Increased Bank Erosion • Loss of Valuable Agricultural Land • Loss of pool frequency and depth, in fact lower Van Duzen goes dry in summer and fall

  9. Timber Harvest • Van Duzen TMDL does not quantify timber harvest • Contributions of logging to cumulative effects are ignored • No limit proposed for logging. • Reeves et al. (1993) found that >25% harvest in 30 years lead to decreased Pacific salmon species diversity • Swanson et. Al. (1998) found 20-30% vegetation removal lead to catastrophic channel change • PL logging rates often exceed 50-80% in a 20 year period and logging hasa continued since TMDL

  10. Timber harvest permit data are only recorded since 1991, when accellerated logging began in 1985 and cumulative effects from those years are likely persistent, especially road networks.

  11. Approximately half the Dairy Creek Calwater Planning Watershed, in the Lower SF Van Duzen was logged with tractors from 1991-2003 posing considerable risk of cumulative watershed effects.

  12. The USFS (1996) Interior Columbia River basin criteria for ecological and hydraulic risk from road densities

  13. PL (1998) HCP data show that road densities in the Lower Van Duzen River watershed are all above levels recognized as properly functioning condition.

  14. Near-stream roads and road crossings pose the greatest cumulative effects risk due to chronic fine sediment yield and catastrophic failures during storms, respectively.

  15. Increased Peak Flows and Decreased Base Flows • When 25% of the area of a basin was impacted by timber harvest and roads, flow increases of 50% resulted (Jones and Grant, 1996). • Roads act as extension of stream courses that can result in major flow increases that can be very damaging to stream channels. • Groundwater interception also decreases sub-surface storage that supports summer baseflows (Montgomery and Buffington, 1993). • No more than no more than 15-20% of a watershed should be in a hydrologically immature state at any given time (Spence et al., 1996) • The combination of reduced base flows and extreme aggradation has actually caused many basin streams like Yager Creek to lose surface flow entirely in later summer and fall, the worst case scenario for fish.

  16. Yager Creek 1997 aerial photo shows streamside landslide likely triggered by high flows and excess sediment transport at bend at upper center.

  17. Large Woody Debris Recruitment Problem • When channels are sediment rich, large wood can help meter sediment and sort substrate into useable spawning gravels • Logging in inner gorges, steep headwaters and unstable areas can reduce large wood recruitment by more than half (Reeves et al., 2003) • Lower NF Yager at left with large wood recruitment greatly reduced due to riparian logging

  18. CDFG found a very high failure rate of instream restoration structures in Grizzly Creek and several other North Coast streams likely due to CWE from logging and roads (increased peak flows, sediment and bedload mobility).

  19. Aquatic Habitat Data • Pool Frequency • Pool Depth • Embeddedness • Aquatic Macroinvetebrates (EPT, Richness, % Dominance • Fine Sediment (<0.85 mm, <4.7 mm) • Median Particle Size Distribution (D50) • Turbidity • Pool Volume (V-star) • Temperature

  20. Pool Frequency by Length

  21. Average Maximum Pool Depth

  22. Embeddedness

  23. Fines < 0.85 mm

  24. Aquatic Macroinvertebrates (EPT)

  25. Median Particle Size (D50)

  26. Median Particle Size (D50)

  27. Turbidity (Klein, 2003)

  28. Turbidity Wolverton Gulch Cummings Creek

  29. Temperature (MWAT)

  30. Temperature (Min, Max, Ave)

  31. June 9, 1877 the Humboldt Times: “Indians, said to be from Hoopa, are fishing in Van Duzen, not far from the bridge. They are successful and the salmon trout they catch are a splendid fish, fat and in fine condition.”

  32. “Fishermen are sweeping the river with seines from its mouth to the Van Duzen. It looks to us as though salmon would be scarce, if not entirely extinct, in Eel River in a few years, with the present way of fishing.” (HT, November 8, 1879).

  33. Coho Extinction Risk HIGH • Coho absent in almost all tributaries of the Van Duzen • Other Eel River sub-populations also greatly diminished; therefore, little chance for replenishment due to “press disturbance”. • Very high risk of extinction due to elevated sediment, loss of pools, loss of LWD, high summer water temperatures, elevated turbidity. • Stock will likely be lost, if freshwater habitat is not improved by the next switch of the Pacific Decadal Oscillation (PDO) cycle in 2015-2025 (Collison et al., 2003)

  34. Steelhead Extinction Risk Summer: VERY HIGH Winter: Declining but LOW risk • Van Duzen summer steelhead now approximately 100 adults • Very high risk of extinction due to elevated sediment, loss of pools, high summer water temperatures, poaching. • Summer steelhead stock will likely be lost, if freshwater habitat is not improved by 2015-2025 (Collison et al., 2003) • Winter steelhead habitat declining: loss of deep pools for older age juvenile rearing, high winter turbidity, high summer water temperature • Winter steelhead spawn late and have plastic life history; therefore, extinction risk is low.

  35. Fall Chinook Extinction Risk Moderate Spring Chinook Extinction Risk Extirpated? • Aggradation and reduced flows create problems for passage. • Shifting bedload due to CWE decreases egg and alevin survival • Limited freshwater rearing is selective advantage • Shrinking estuary due to sediment reduces growth and survival of juvenile chinook

  36. Sturgeon Extinction Risk VERY HIGH Extirpated? James Smith caught a sturgeon in the Van Duzen which weighed 125 pounds and was 6 feet 2 inches long. (HT, April 7, 1883). “More than one hundred large sturgeon have been killed in one deep place in Eel River, near the mouth of Van Duzen, in the last month (HT, August 6, 1877).”

  37. Cutthroat Trout Extinction Risk Extirpated? • Van Duzen and Eel River are furthest southern range • Very intolerant of increased water temperature • Juveniles prefer pools, similar to coho, and pools have diminished. • No cutthroat found in the Eel River since 1991 (Stitz Creek)

  38. Yager Creek electrofishing survey results from 1991 CDFG habitat typing survey. Dominance of warm water adapted California roach shows advanced habitat degradation.

  39. Juvenile northern pikeminnows can be distinguished by the strong, purple lateral line midway down the fish’s sides. Introduced to Pilsbury Reservoir circa 1985, this predator thrives in warm water.

  40. Setting Prudent Risk Limits to Disturbance

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