FLOOD04031

• County: Statewide
• Community: State of Colorado
• Stream Name: All
• Basin: Statewide
• Title: Subdivision Design in Flood Hazard Areas
• Date: 9/1/1997
• Prepared For: State of Colorado
• Prepared By: FEMA
• Floodplain - Doc Type: Educational/Technical/Reference Information

the floodplain. Bonus provisions are used to achieve a
number of other purposes as ,veIl, most often
affordable housing. Density bonuses are most
effective in areas v\There the permitted density is very
1m'\' and greater increases can be allowed \vithout
compromising the lands that are being set aside
(Arendt 1994).

credit for portions of a subdivision that cannot be
developed because they are classified (according to the
ordinance's definition) as a sensitive area or buffcr,
which includes floodplains. \Vhatever dcvelopment is
allO\'\'ed is sited on land that is not environmentally
restricted. The credits are calculated on a sliding s~ale,
ranging from a 100 percent density credit in cases where

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In \Vashington County, Oregon, a developer \\'ho uses
the cluster option can build to one unit per eight acres,
vvhereas the density limit for conventional subdivisions
is one unit per 10 a~res. Clark County, V\.'ashington,
a11o\\'s clustered subdivisions to be developed at one unit
per fivc acres, plus an additional two dwellings for every
20 acres in the project; conventional developments are
limited to one unit per 20 acres (Salkin 1991).
King County, \Vashington, through its Sensitive
Areas Ordinancc, offers developers partial density

The> [ndiall Bend Wash in
Scottsdale, Arizona, i$ a four~milc-
Ion;.: green way designed 'to handle a
1 ()Q-year flood as a mealls of
protcctillg adjacent residential
neighborhoods from flooding. The
wash provides open space, grass,
golf C01lrses, hall fields, hiking and
bicycle trails, and picnic arcas. The
wash was completed in 1979 and is
a jOlllt pro/ccf of the U.S. Army
Corps of Engineers, fhe Maricopa
COllllt1! Flood Control District, and
tile City of Scottsdale.

10 percent of the property is in the floodplain to a 20
percent credit in cases where 90 percent of the property
is in the floodplain.
Fairfax County, Virginia, applies a special density
limit to parcels in which 30 percent or more of a parcel
is in the floodplain. In such cases, 50 percent of the
maximum permitted density is calculated for that area
of the parcel which exceeds 30 percent of the total area
of the parcel. For example, if 45 percent (45 acres) of a
laO-acre parcel's land area is in a floodplain and the

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