stream protection for the city of los angeles · courtesy eco-village from the los angeles public...

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


Bell CreekPhoto: Jessica Hall


Dayton Creek at Orcutt Ranch

Photo: Jessica Hall


in Hollywood Hills in Los FelizPhotos: Jessica Hall

From the UCLA Geography Fairchild Air Photography Collection


Flight #H-73 11/29/1929

Stone Creek

Photo: Jessica Hall


Hoag Canyon

Photos: G. Haines

GoogleEarth


In Brentwood, near Wilshire

Photo: Jessica Hall


Bundy CreekPhoto: Natural Channel Design


Brown’s CanyonPhoto: Natural Channel Design

Photo: Natural Channel Design


Limekiln Creek



in Lincoln Heights

Photos: Jessica Hall


At Peck Park, San Pedro



The Bixby Slough/Wilmington Drain

Photo: Jessica Hall


Arroyo de las Pasas

gone

From the UCLA Geography Fairchild Air Photography Collection


Compton Creek

gone

From the Los Angeles Public Library



Ballona Creek

gone


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



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


Protected floodplains reduce liability


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




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




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





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: 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?

stream protection for the city of los angeles · courtesy eco-village from the los angeles public...

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