stream protection for the city of los angeles · courtesy eco-village from the los angeles public...
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Stream
for the city of
Los Angeles
Fall 2009
Protection
A Discussion
Streams?
What
streams?
In Council District 2
La Tuna Canyon
Photo: Jessica Hall
In Council District 3
Bell CreekPhoto: Jessica Hall
In Council District 3
Dayton Creek at Orcutt Ranch
Photo: Jessica Hall
In Council District 4
in Hollywood Hills in Los FelizPhotos: Jessica Hall
From the UCLA Geography Fairchild Air Photography Collection
In Council District 5
Flight #H-73 11/29/1929
Stone Creek
Photo: Jessica Hall
In Council District 5
Hoag Canyon
Photos: G. Haines
GoogleEarth
In Council District 11
In Brentwood, near Wilshire
Photo: Jessica Hall
In Council District 11
Bundy CreekPhoto: Natural Channel Design
In Council District 12
Brown’s CanyonPhoto: Natural Channel Design
Photo: Natural Channel Design
In Council District 12
Limekiln Creek
Photo: Natural Channel Design
In Council District 14
in Lincoln Heights
Photos: Jessica Hall
In Council District 15
At Peck Park, San Pedro
Photo: Natural Channel Design
In Council District 15
The Bixby Slough/Wilmington Drain
Photo: Jessica Hall
In Council District 1
Arroyo de las Pasas
gone
From the UCLA Geography Fairchild Air Photography Collection
In Council District 1
Arroyo de las Pasas
gone
From the UCLA Geography Fairchild Air Photography Collection
In Council District 9
Compton Creek
gone
From the Los Angeles Public Library
From the Los Angeles Public Library
In Council District 10
Ballona Creek
gone
In Council District 10
Arroyo La Brea
gone
“Forty-five acres of ground, now a
waste…will be reclaimed for use - when
this slough...is filled in. The live stream
of this creek now flows through the
Sacatela No. 3 storm drain, leaving no
excuse for the gullies and ravine which
now exist.”
- Los Angeles Times, 1930Courtesy Eco-Village
From the Los Angeles Public Library
In Council District 13
Sacatela Creek
gone
Throughout LA City
The norm
Dry Wash
Intermittent
Perennial
Wetlands
Early 20th Century Streams
94 miles
312 miles
148 miles
9 sq. miles
Historic Streams in
Los Angeles area
Over 90% loss of
streams & wetlands
Map: Jessica Hall
replenish beaches
soil fertility
building materials
water quality
flood protection
drinking water
recreation
property values
microclimate
carbon sequestration
biodiversity & habitat
economic welfare
BenefitsStream functions
groundwater recharge
sediment transport
flood storage
stormwater conveyance
habitat
Image: Jessica Hall
Natural streams work for us - for free!
Types of Streams
Photo: Jessica HallPhoto: Jessica Hall
Usually look dry
Only have water during rainy season
Important for water quality, recharge &
habitat
Ephemeral Streams Intermittent & Perennial Streams
Usually wet or moist
Runs year round or part of year
Most people’s idea of a stream
Caballero Creek, CD 3 Caballero Creek, CD 3
HIGH
TERRACE:
Rarely flooded
CHANNEL:
Carries low flows;
bedload sediment
GEOMORPHIC
FLOODPLAIN:
Commonly
flooded
LOW TERRACE:
Infrequently flooded
Streams have one or more channels, a floodplain and terraces.
Slide data
from Stream
Assessment
&
Restoration
Design
Workshop,
by Tom
Moody, PE,
Natural
Channel
Design, Inc.
Parts of a stream
Photo: Natural Channel DesignAliso Creek, CD 12
Natural Streams Protect Water Quality
Streamside plants and
organisms remove and
break down pollutants like
nitrogen and total
suspended solids.
Photo: Jessica Hall
Wonderland Creek, CD 5
Natural streams support biodiversity
LA lost its salmonids with
channelization of LA and
San Gabriel Rivers.
West Coast commercial
salmon fishery at point of
collapse.
Maintaining local fisheries
maintains food security.
And biodiversity supports you and me.Photo: Jessica Hall
Photos courtesy Wendy Sue Rosen
Loss of streams = loss of habitat
Mandeville Canyon, CD 11
Helianthus nuttallii parishii
Los Angeles Sunflower
http://www.geocities.com/royvandehoek/losangelessunflower.htm
Potentilla multijuga
Ballona Cinquefoil
Loss of streams = extinctions
Co
urt
esy P
asad
ena
Muse
um
of
His
tory
Arroyo Seco 1885
streams are human habitat
streams are human habitat
Photo: Jessica Hall
Floodplain After Filling
Slide from: No Adverse Impact, Association of State Floodplain Managers
Protected floodplains protects property
Slide from: No Adverse Impact, Association of State Floodplain Managers
Protected floodplains reduce liability
Slide from: No Adverse Impact, Association of State Floodplain Managers
as measured by:
• increased flood peaks & flood stage
• flood velocity
• erosion and sedimentation
The City of Los Angeles is
also obligated to prevent
increases in flood peaks and
stream velocities under its
MS-4 Permit.
Protecting floodplains reduce liability
Stream Buffer Benefits:Provide Economic Value
• Minimizes Flood Mitigation
• Increases Property Values
– $10,000 or more in Virginia
(Tippett et al., 1999)
– Values of Homes Increase as far as 3 Blocks from the Stream (Vince Graham, ION Development)
– Property Values 32% Higher for Locations Adjacent to a Greenbelt Buffer in Boulder, Colorado (Correll et al. 1978).
• Increases Tourism
Slide content from: Stream Setbacks and Buffers: Adding Value to Your Community through Stormwater and Natural
Resource Conservation, for the Johnson County Stormwater Management Program & Mid-America Regional Council,
By: Black & Veatch, Inc., Tetra Tech EMI, and Patti Banks Associates.
Protecting streams enhances property values
$150,000
$175,000
$195,000
$195,000
Slide content from: Stream Setbacks and Buffers: Adding Value to Your Community through Stormwater and Natural
Resource Conservation, for the Johnson County Stormwater Management Program & Mid-America Regional Council,
By: Black & Veatch, Inc., Tetra Tech EMI, and Patti Banks Associates.
Protecting streams enhances property values
Managing streams
Not all streams are mapped accurately
Photos: Guangyu Wang
Arroyo del Jardin de los Flores, CD 4
CEQA and the Clean Water Act require mitigation not
protection for filling a stream.
1976. Kenter Creek, CD 11. 2004. Kenter Creek, CD 11
Managing streams
State and Federal laws do not stop streams from being destroyed.
Map and Aerial: Microsoft Terraserver
Creek in the Los Angeles River headwaters (CD 12) at risk.
Whoever bought this creek can legally fill it or line it in concrete.
Managing streams
State and Federal laws do not stop streams from being destroyed.
Photo: Jessica Hall
Kenter Creek, CD 11
•Construction to
edge of banks
•Grading in
streambed
•Check dams and
other construction in
stream channel
•No stream buffer
•Diversion of flows
Erosion
Bank instability
Poor water quality
Sedimentation
Habitat loss
•Stream originally
“unmapped”
Managing streams
Local jurisdictions should be the front lines of stream protection.
ISSUES RESULTS
Photo: Jessica Hall
Stone Canyon Creek, CD 5June 4, 2006
Managing streams
Photos: Jessica Hall
Local jurisdictions should be the front lines of stream protection.
Whoever bought this creek can legally fill it or line it in concrete.
Las Virgenes Creek - $1.5 m $2,800/linear foot
Dry Canyon Creek - $500k $900/linear foot
Managing streams
Protecting streams costs less than restoring them
Stream protection: mapping & city Plan Check
•Adding City streams to
Navigate LA
•Ensuring plan check includes
consultations with:
California Department of
Fish & Game
US Army Corps of
Engineers
Regional Water Quality
Control BoardAtwater Creek, CD 4
Photo: Jessica Hall
•Creating a Stream
Identification Zone
Buffer Architecture• Three-zone buffer is preferred
• Progressive zones allow more intensive uses
• 100 foot minimum recommended
• Johnson County Model:
– Streamside zone (25 ft.)
– Middle zone (50 ft.)
– Outer zone (25 ft.)
Stream protection: using buffer zones
Slide content from: Stream Setbacks and Buffers: Adding Value to Your Community through Stormwater and Natural
Resource Conservation, for the Johnson County Stormwater Management Program & Mid-America Regional Council,
By: Black & Veatch, Inc., Tetra Tech EMI, and Patti Banks Associates.
Variations on the Theme
• Shawnee, Kansas:
– Two zone buffer
– 25-yr floodplain plus 90 feet
– No habitable structures allowed within buffer
• Liberty, Missouri (tentative):
– Either 100 feet top-of-bank or 100-yr floodplain, whichever is greater
– Uses within buffer may be limited to recreational trails
Slide content from: Stream Setbacks and Buffers: Adding Value to Your Community through Stormwater and Natural
Resource Conservation, for the Johnson County Stormwater Management Program & Mid-America Regional Council,
By: Black & Veatch, Inc., Tetra Tech EMI, and Patti Banks Associates.
Stream protection: using buffer zones
California Variations on the Theme• Berkeley, CA:
– Buffer includes culverted (piped) streams
– No structures with roofs allowed within buffer
– 30’ setback from stream centerline
• Oakland, CA:
– 2 levels of protected zones: a 20’ and a 100’ setback from top of bank
– Creates 4 classes of permit depending on proposed work within each zone.
– Permittees must submit a thorough Creek Protection Plan with their building submittals.
• Sonoma County, CA
– 50’ setback of streams in urban and upland areas (proposed to be widened to 100’),
– 100’ setback in lowland streams
– 200’ along the Russian River.
• Coastal Zone, Coastal Commission, CA
– 100’ setback from edge of riparian canopy
Stream protection: using buffer zones
Stream protection: ordinancesOakland, California
Berkeley, California
San Diego County, California
Santa Cruz, California
Napa, California
Austin, Texas
La Grande, Oregon
Charlotte, North Carolina
Mecklenberg, North Carolina
Cannon Township, Michigan
Peabody, Massachusetts
Joliet, Illinois
Fairfax County, Virginia
Kings County, Washington
Washoe County, Nevada
The State of New Jersey has
proposed a 300’ Riparian Buffer
along “Category 1” streams.
The State of New Jersey
Photo: Jessica Hall
Stream protection: questions and discussion
Photo: Jessica Hall
Los Angeles River, CD 6
•Stream Mapping
•Stream Identification Zone
•Stream Buffers
•Stream Protection Ordinance
Stream Protection Concepts
•Others?
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