HomeMy WebLinkAboutAgenda Bill 6.A-Attch14 09/20/20041 +
. � � � T L � � - , � � T � 7400 N. DUTTON AVE., SUITE 24
1 1 "v, SAN "IA ROSA
H O' 'M E S 1 ; rC CA�iFORN�A 954D:1 - 4.643
C r e a,, t t: n q TEL: 707528,-8703
FAx: 707:.528- 6125
July 20, 2UU4.
JayniAllsep
City Hall 4 t�
, �.EC
11 English Street -� %UJ
Petaluma, CA 94.95.2
, CUM'
UNIl�'�ut�rtWhMO I UtPARrM`ENi
Re: Riverview
Dear Jayni:
You will find attached the study of Lot 49 as a play area; There are several' problems
with the proposal, and "it;appears'to'"create several difficult situatioris.
Lot 49 has a significant slope and tree cover. In order, to create a. level play area, a six-
foot high retaining, wall will "be required at the corner. Access to. the front of:the "park
would. be through stairs, and "the handicap ;access° bedornes difficult due to the grade and
slope conditions: Since�the wall' creates• a substantial vertical- condition, a protective
fence will be required onFthe top of the wal'l.. Additional planting; and irrigation will be
restricted due'to the:ezte*nsiue"tree canopy. Any Use of the area would be limited due to
the "constrained play area.
The "new" Lot 49 location, and Lot 2 -5 along Mission Drive will be marginally close to
the drains a area at "the rear of the lots; and.due to the lot slope,.
a. two to three foot
g
retaining wall will be requir.ed;at he rear of the properties Property line fences will be
on top of the wall creating-an eight , to nine _foot vertical condition Arid the property lines
will be' close to the •watercourse, ,
In summary, Lot 49 play area has limited utility and furietion. We believe the Tentative
Map reviewed °`:by the Planning Commission is the preferred alternative, as it, has, the least
inipact on, the property:;
You l:
Frank Denney
Vice President, perations
CA L N Z 0 L C
-A N D -
ASSOCIATES
Civii.Enkinem - Land Surveyors - Plan,lzers
June: 24,, 2004.
City of Petaluma
Community Development Department rj�j
P.O. Box-61
Petalu 949:53
Attn: Kim Gordon J J
Subject: Report on Alternate Layout Study for Riverview
Kim,
At the request of the Planning Com m is sion, "
w a-a alternate : street
e, proceeded to study a
alignment Or Missio Drive and Rovina Lane. The alternate on a
sketch dated •6/7%04 was'used as base f6r street alignment and lot layout.
We found that out stre.etr layout could- conform closely With the 'sketch provided
ded,
hoWovb( we. needed, to add the street tree planter strip, the sidewalks, the property
lines and the P.U.E.'s to the layout' as t he sketch only 7shows the istreet ftom - curb to
- curb. We Modified th.effitersection, of Rovina Lane and Jacquelyn Lane l .to prov"ide
intersection,, an le, more nearly ninety - degrees in keeping wifh, standard City
requirements. This was done by curving' J acquelyn Lane slightly before - the
intersection, which did not impact the proposed talignment of Rovi ' Lane Lane and did. not
impact any trees..
After refining the: . t aliciffMeht the he street g were checked using full - profile
design of the streets and 'proposed, intersections. We foubd that to achieve an
intersection. with Mission Drive, Rovina L ' a'nci needed to be 15% grade for nearly the
,entire length of the street, including throu the intersection with, Jacquelyn Lane. The
reason, for a steep`er,grade,,for a longer stretch i that the new intersection with Mission
Drive is 10 ,feet higher than the.alignment previously proposed for ',the same 'l hath of'
street We . noted that' the. grades shown on the, sketch, Were figured, using a 12 %
to, the center of the 'intersection. We had Lto` allow grade transition at the., intersection
and chose a short 50400t vertical curve to go from a''5% ,grade at the .'intersection: to a
.1 5% forthe street. A short 5 area was left at the, intersection for tar to Wait
before turning onto Mission Drive. ]t is anticipated that We can make the handicap
ramps work at the comers of the MissionlRovi.00 intersect I ion, if they are pulled back
from Mission, Drive !somewhal . However, at the Jacquelyn Lane 'Lane
'intersection,,, the- ' grades are more, sign due to the 15% gfa th.rQugh,* the.
intersection. The grades at the corn are shown; at near 20 0
r o s. the handicap
ramps will need to be quite a, distance from the intersection to.meet code. The location
has not been fully worked out in this study. To reduce grades 8 little the comers, we
had to raise Jacquelyn Lane and increase jhefogth of the retaining: wal along the
Northerly line of the street right-:of-Way.
dtorres\1826 I\LettersWltLayoOtRiAdwitcdoc 1'1T1 ACHMEN1 14
325 TES CIRCLE LEROY'CARLENZ,O 1 -6465
(707') 542
SANTA RosA, CA 95401 R.C.E_No:'179'13 VAX (707) 5424645
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Iri order to reduce tree impacts, .we tried placing the sidewalks along Roving Lane and
Mission Drive adjacent to the curbs,. We also studied the use' of ,retaining walls behind
the sidewalk. The grading impacts using retaining walls were greater than.the impacts
of the-cut and fill slopes so we did not show retaining walls U-nder the trees.
Once the streets, sidewalks and right -of -way lines were shown, the lot lines for the lots
could be added. Please, note that substantial modifications of the lots was required in
the area of Lots 56 to 59. Due to the - tighter lot configuration and the grading
challenges,_ the:_ home types were modified for several &`these lots-. Also note: that Lot
25 has a retaining wall. proposed at the rear lot line to protect that lot from 'potential
blockage of the drai -Wage in the open space channel since the setback. from the lot to the
creek is significantly reduced from the 25 30 feet provided on other lots.
What is not readily apparent on the resulting alternative study is the tree pruning and
root disruption, which accompanies road and utility construction: The construction of
roadways, on slopes.requires keyways below. the toe. of the :fill slopes. as a basis for the
fill. In addition, the fill slopes fare built larger than the design shows in order to trim back
the uncompacted fill on the face:of slope. 'The con.$tructio.n equi 'pment needed to do
this work requires room. to work the tree 1'imbs which, results in .the loss of
trees which are too 'close to ,the cut'or fill slopes.
Several homes have moved as a result of the 'street alignment change. Homes which
are under the tree canopies,, result' in removal;- of limbs for the two-story -height of the
house. In addition, grading for. foundations results' in destruction of the root zones.
Although the underground'utilities are not shown on this alternate layout, the street.area
from P.U.E. line to RUE'. fine, has utility trenches which cut into the root zones of the
trees. The public utility ;trenches should ' be. head to the fill side of the roadways to
minimize impacts to tree roots. This may result, however, in impacts to low hanging
tree limbs.
hope that we have, provided an adequate picture of _the ,.issues involved with the
alternate layout. If there are any,questions we can help answer, please contact us.
Regards, ,
Carienzoli and Associates
BONNIE'DIEFENDQRIF
Q: \Corres\ 1826_1 \Leiters\HltLayoutR mewltr.doc
6/24/2004
CA.R C E N Z O L I
A N '1)
AS50',CIATE;S
Civil Engineers — Land'Survcyors� Planners .
July 19, 2004
City of`Petaluma
Community Development Department
11 .English Street
Petaluma,, CA 94952 -2610
Attn: Jayni.Allsep
Re: Riverview Subdivision`
Dear Jayni:
Attached is the .Alternative Layout for a park on what we .had proposed" as Lot 491.
Also !included is a revised .cross - section through the site showing the 'grades and
proposed level area.,
Du,e to the grades on (this site, extensive; fill would;`be required to provide a 'level area
for park facilities and handicap access. A handicap - accessible path is :shown on the
.west sides of th=is park site. Minor grading under tree d'riplines is required 'to grade
this path.
if there are any questions, pleas=e call.
Sincerely,
CARLENZOLI AND ASSOCIATES'
BONNIE.A, DIEFENDORF
O: \Corres \1826_1 \LehersUayniAll sep2 :doc
7/19/2004 -
325 T ESCbNI CIRCLE
SANTA ROSA, CA 95401
1 of
LEROY CARLENZOLL
R.C.E..'No. 17913
(707) 542' 6465.
' FAX 1 i707') 542-1645
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