Horse Creek DamolitionHorse Creek Damolition

Presenters:Matt Stoecker, Stoecker

Ecological and

Thomas B. Dunklin Productions

Presenters:Matt Stoecker, Stoecker

Ecological and

Thomas B. Dunklin Productions

Horse Creek

Santa Barbara

Sisquoc River Steelhead Barrier Assessment and

Recovery 2003

Sisquoc River Steelhead Barrier Assessment and

Recovery 2003 Funded by the Coastal Conservancy Identified migration barriers Historic steelhead documentation/current observations Habitat assessment Prioritize barriers for fish passage projects

Funded by the Coastal Conservancy Identified migration barriers Historic steelhead documentation/current observations Habitat assessment Prioritize barriers for fish passage projects

Key FindingsKey Findings

Santa Maria R. was 2nd largest steelhead run in SB Co. Twitchell Dam (1950’s) blocked 264 miles, Cuyama R. Majority spawners used Sisquoc R. (Shapovalov, 1945) Over 203 miles historically accessible in Sisquoc River. Abundant high quality spawning and rearing habitat. Historic documentation and current wild O. mykiss

population. 31 anthropogenic barriers identified, plus natural

barriers. Horse Creek Dam blocks the most habitat at 19 miles Most limiting factor to Sisquoc steelhead is reduced

surface flow for migration on the Santa Maria River caused by inadequate releases from Twitchell Dam and excessive groundwater withdrawal

Santa Maria R. was 2nd largest steelhead run in SB Co. Twitchell Dam (1950’s) blocked 264 miles, Cuyama R. Majority spawners used Sisquoc R. (Shapovalov, 1945) Over 203 miles historically accessible in Sisquoc River. Abundant high quality spawning and rearing habitat. Historic documentation and current wild O. mykiss

population. 31 anthropogenic barriers identified, plus natural

barriers. Horse Creek Dam blocks the most habitat at 19 miles Most limiting factor to Sisquoc steelhead is reduced

surface flow for migration on the Santa Maria River caused by inadequate releases from Twitchell Dam and excessive groundwater withdrawal

Historic Steelhead Documentation

Historic Steelhead Documentation

Sisquoc River 1916 (above) “ The stream is so full of mountain trout. I am

confident that we saw in some places more than 500 at one sight….and had no difficulty capturing all we wanted with our hands.” Stephen Bowers 1879

Sisquoc River 1916 (above) “ The stream is so full of mountain trout. I am

confident that we saw in some places more than 500 at one sight….and had no difficulty capturing all we wanted with our hands.” Stephen Bowers 1879

Current Steelhead Documentation

Current Steelhead Documentation

Sisquoc R. Habitat

Sisquoc R. Habitat

Sisquoc R. Steelhead Survey 2005

Sisquoc R. Steelhead Survey 2005

Adult Steelhead over-summering 6 feet down in a cave under this bedrock ledge.

Adult Steelhead over-summering 6 feet down in a cave under this bedrock ledge.

Funded by DFG

Looking up Horse Creek Canyon

Looking up Horse Creek Canyon

Dam

Sisquoc River

Horse Ck. DamHorse Ck. Dam Built 11/3/1969 after

Wellman Fire Sacrete bags on

concrete footing, with re-bar

Dam crest 62 feet Dam height 10 feet

(5’ Dam, 5’ perched) Filled with sediment Stream gage, never

used

Built 11/3/1969 after Wellman Fire

Sacrete bags on concrete footing, with re-bar

Dam crest 62 feet Dam height 10 feet

(5’ Dam, 5’ perched) Filled with sediment Stream gage, never

used

Horse Creek Habitat and Barriers

Horse Creek Habitat and Barriers

21.8 mi2, 1000-5000’ elev

Dam 850 feet upstream from Sisquoc River

19 miles of habitat (poor to good) upstream of dam to natural barriers.

Both perennial and intermittent reaches.

No trout observed, Arroyo Chub present.

21.8 mi2, 1000-5000’ elev

Dam 850 feet upstream from Sisquoc River

19 miles of habitat (poor to good) upstream of dam to natural barriers.

Both perennial and intermittent reaches.

No trout observed, Arroyo Chub present.

Horse Ck. Upstream of the DamHorse Ck. Upstream of the Dam

Also Upstream in Horse Creek

Also Upstream in Horse Creek

Channel Assessment Study 2005

Channel Assessment Study 2005 Funded by American

Rivers/NOAA Fisheries Michael Love and Assoc.

and Stoecker Ecological Longitudinal Profile

2,200’ 7 channel cross

sections 2 downstream, 1 at

dam, 4 upstream Wolman pebble count of

stored sediment 250’ u/s

Funded by American Rivers/NOAA Fisheries

Michael Love and Assoc. and Stoecker Ecological

Longitudinal Profile 2,200’

7 channel cross sections

2 downstream, 1 at dam, 4 upstream

Wolman pebble count of stored sediment 250’ u/s

Plan MapPlan MapPlan Map

Longitudinal Profile Survey

Sediment Deposit Upstream of Dam

Sediment Deposit Upstream of Dam

Horse CreekHorse Creek

Cross Section at DamCross Section at Dam

Downstream Reference Channel

Downstream Reference Channel

Anticipated Removal Outcome

Anticipated Removal Outcome

Channel incision 2,321’ upstream 15,400 cubic yards of sediment u/s mobilized

(Annual Sisquoc R. 255,000-367,000 yd3)4-6% increase in one year, but will take more

Sediment released relatively course (gravel and cobble) Wolman pebble count.

Minimal to no negative impacts downstream Unobstructed wildlife/fish passage and

improved habitat and surface flow upstream

Channel incision 2,321’ upstream 15,400 cubic yards of sediment u/s mobilized

(Annual Sisquoc R. 255,000-367,000 yd3)4-6% increase in one year, but will take more

Sediment released relatively course (gravel and cobble) Wolman pebble count.

Minimal to no negative impacts downstream Unobstructed wildlife/fish passage and

improved habitat and surface flow upstream

The Preferred AlternativeThe Preferred Alternative Removal Obsolete Not consistent with

Wilderness and Wild Scenic management

Most effective fish and wildlife passage

Restore surface flows and channel complexity

Inexpensive vs. fishway

Removal Obsolete Not consistent with

Wilderness and Wild Scenic management

Most effective fish and wildlife passage

Restore surface flows and channel complexity

Inexpensive vs. fishway

Explosives Staged release of sediment

not necessary No danger to people Difficult access Inexpensive vs. heavy

equipment Reduced impact to bank and

channel DFG and CCC technical

support and explosives (ammonium nitrate) available for project

Interest in gaining experience/knowledge with this technique

Explosives Staged release of sediment

not necessary No danger to people Difficult access Inexpensive vs. heavy

equipment Reduced impact to bank and

channel DFG and CCC technical

support and explosives (ammonium nitrate) available for project

Interest in gaining experience/knowledge with this technique

Detonation Cords Going Off

Detonation Cords Going Off

Coastal Conservancy, Los Padres Nat. Forest, American Rivers, NOAA Fisheries, Dept. Fish and Game, California Conservation Corps, Community Environmental Council, Sisquoc Ranch, Thomas B. Dunklin Productions/Joan Dunning, Stoecker Ecological, Forest Watch

Coastal Conservancy, Los Padres Nat. Forest, American Rivers, NOAA Fisheries, Dept. Fish and Game, California Conservation Corps, Community Environmental Council, Sisquoc Ranch, Thomas B. Dunklin Productions/Joan Dunning, Stoecker Ecological, Forest Watch

Un-Dam it and they will come!Un-Dam it and they will come! Matt Stoecker Matt@StoeckerEcological.com

Photo/Assistance thanks: Bob, Doug, Jim Stoecker Thomas Dunklin Michel Love Shaw Allen Kevin Cooper Tony Llanos Donna Toth

Matt Stoecker Matt@StoeckerEcological.com

Photo/Assistance thanks: Bob, Doug, Jim Stoecker Thomas Dunklin Michel Love Shaw Allen Kevin Cooper Tony Llanos Donna Toth