Page 192 - Des Moines - Zoning, Planning and Design Ch 134, 135

135-3. lArGe-ScAle DeVelOPMeNt
Streets and Blocks
135-3.2 Streets and Blocks
3.2.1 BlOcKS AND AcceSS
Each development shall contribute to an
interconnected system of streets and blocks through
the following requirements.
A. Maximum Block Size. Streets shall be located to
result in the following block requirements.
1. For MX and DX districts, maximum block face
length shall be no more than 400 feet in length.
2. For all other districts, maximum block face
length shall be no more than 600 feet.
3. The maximum perimeter of any block shall be
1,600 feet. 2
4. Blocks may be split at the development
boundary between the submitted development
and an abutting site.
a. The function of the full block shall be
considered to allow completion on the
abutting site.
b. The partial block shall meet and the
full block shall be able to meet the
requirements of this section, 135-3.2.
c. Blocks shall be located on the site to allow
full completion, so that rears of parcels do
not front a street.
5. Streets shall connect and continue existing
streets from adjoining areas.
6. Type 1 design exceptions for block size and
street location may be applied for per XXX and
under the following conditions:
a. The inclusion of a CX district requires
a deeper block to allow parking on the
interior.
b. Natural constraints, such as waterways,
slopes, or other natural features, exist
precluding the location of a new street.
c. Abutting development conditions affect the
develop-ability of the applicable site.
d. Study of the extension of the system of
streets and blocks illustrates an adjustment
to the requirements of the site.
B. Access Points. An access point is a new street
connecting to an existing street or a new street on
an abutting site.
2 Recommend expanding this to 1800 feet with the MX
district block face separate requirement..
135-3-6
DRAFT
1. A minimum of two access points shall be
provided for each development.
2. A minimum of one access point is required per
every 1,600 feet of the perimeter of the Large-
Scale Development. A type 1 design exception
may be applied for a reduction in the number of
access points on the perimeter.
3. Temporary dead end streets or stub streets are
permitted at an abutting property boundary to
allow for future connection.
c. Block and lot configuration. The shape of blocks
and lots shall be generally rectangular in order to
accommodate typically rectilinear buildings, but may
vary due to natural features or site constraints.
1. Blocks shall typically be two lots deep with the
exception of blocks containing open space.
2. Double frontage lots shall be avoided; the rear
of lots shall not front streets. Refer to 135-3.3
for primary street designation and frontage
requirements for lots.
3. Blocks shall be fronted with lots or buildings
on at least two faces, preferably on the longest
street faces.
4. All lots shall have full width frontage along a
street unless otherwise specified in building type
requirements.
5. Flag lots are prohibited.
6. The configuration of the blocks shall consider
alley inclusion required per 135-3.2.3.
7. Blocks may include existing lots within an
existing district.
8. Lots and blocks shall be oriented for maximum
feasible energy efficiency, depending on the
building type. For example, block orientation
along an east-west longitudinal axis will
encourage development of long buildings
oriented along an east-west axis, with smaller
east and west facing facades, able to take
advantage of passive solar technology.
3.2.2 StreetS
A. cul-de-Sacs and Dead end Streets. Cul-
de-sac and dead end streets require a type 1
design exception and are permitted only when
necessitated by natural features or site constraints,
including but not limited to rail corridors, waterways,
or highways. If allowed, pedestrian connections
through the cul-de-sac may be required.
DRAFT AUGUST 3, 2017