5. Sidewalk Deficienciesv :iM1y
IC Workn Dgc1partmial-it
ell" 11 Publ*c
k'/Ity of &a ispe
,v.......:.- :. w: •me.};n v:..,wN 2
<`. Post f. Boy- . , :K , M 99 � 9 f � h � ..
TO: James H. Patrick, City Manager
FROM: James C. Hansz, .E*, Director Pubs
SUBJECT: Sidewalk Construction Deficiencies
DATE: 30 September 2005 (UPDATED DECEMBER 6,2005)
SUMMARY
Eight subdivisions are under construction by various developers. Their Subdivision Improvement
Agreements require public infrastructure to 'be designed and constructed in accordance with City
standards. The developers of the eight subdivisions all have, to varying degrees, failed to ensure that
sidewalk are constructed IAW City standards. The total of substandard sidewalks is significant,
approximately 25,903.LF, or % of the sidewalks constructed. Of this total, approximately 7,666 L
should he replaced outright. The remaining sidewalks .have, to some degree, a value that is less than the
C ity's standard sidewalk, but is great enough to warrant allowing thei to remain in place provided that a
reasonable and equitable method for determining g their serviceable value can be identified and satisfactory
compensation for this reduced value can be agreed. This is desirable in order to protect the public interest
while minimizing the adverse impacts on a jaeent properties if the sidewalks were to be replaced. Staff'
has identified a possible method for resol.vin.g this problem.
BACKGROUND
In ;tune, Public works staff identified a problem with the construction of some sidewalks in the
Ashley ey Park Phase 7 subdivision. The problem areas were brought to the attention of the
developer/engineer. Subsequent to that notification, , the developer's subcontractor installed the s1dewalk
without providing the correct granular base .material. detailed discussions with the developer/engineer
then followed which subsequently led to a general quality assurance Q test program by PWDto
ascertain whether other new sidewalk construction by contractors working for propel developers has
been done 1n conformance to the City" s long-standing specifications. The results of the QA testing reveal
a significant problem witb sidewalk construction in the other new subdivisions.
'Discussions with the developer/engineer for Ashley Park Phase 7 Included potential remedies.
The options discussed included outright replacement, extended warranty, possible payment of a. penalty,
and consideration for the value of workperformed. At the present time, City standards only provide for
replacement of the non-standard items, This was communicated to the developer/engineer. As a result, the
matter was discussed in detail with the City Council at a -work session*
During the work session discussion, multiple areas of concern were identified by the City
Council. The concerns .included the issue of contract performance with respect to the Subdivision
Improvement Agreement that exists between the City and the Developer for Ashely Park Phase 7. Also of
concern is the extent of -the problem with other subdivisions, potential disruptions and inconvenience to
homeowners adjacent to areas of possible sidewalk replacement, potential future City liability for
premature replacements of sub -standard sidewalks left in place under extended warranties, determination
of an appropriate value of non --standard sidewalks, and difficulties in obtaining and administering
extended warranties beyond the normal one-year warranty that accompanies all new construction. Staff
was directed to further examine these concerns and identify any potential solutions for the current
problem..
EVALUATION
The Ashley .Park Subdivision Improvement Agreement (SIA) stipulates that all public
infrastructure improvements will be designed and constructed tructed in accordance with City of Kalispell
standards. The developer/engineer for Ashley Park Phase 7 has acknowledged that the sldewal s do not
meet City standards, .Project design documents clearly show the intent for the project to meet City
standards. Quality Assurance (QA) tests confir . that construction has failed to match the intent of the
design and the letter of the S .A. Similar QA tests have confirmed the same problem i . other development
projects. The extent of the problem in other subdivisions under construction is as follows:
Subdivision Total SW Mstalled Total OK Total Deficient
Ashley 7
3J.55 LF
300 LF
2X5 LF
Blue Heron 1 &2
47828 LF
Il 500 LF
3328LF
Empire Estates 1, ,&
13,630 LF
5,700 LF
7,930 L
G1ac'er village Greens 1 &2
2,(
.`
Leisure Heights 1&2
8.230 0 LF
100 LF
6,430 LF
Stratford Village
�4,�7 0 LFl
,20LF�,
LF
Sunnyside 2
31)o LF
2, 100 LF
11,7500 L
Three Mile*
425 LF*
Grand Total
40,568.
14,665 LF
251J903L
Three Mile Subdivision sidewalks are being installed by individual home builders as each residence is
completed. At the present time 42S LF of sidewalk is confirmed deficient. Each section completed by
indIvid .al contractors is subject to testing to confirm compliance with standards prior to release of bond.
Totals do not include Three Mile Subdivision because QA. testing is still in progress.
memo0442005.doc
The total quantity of sidewalk that does not meet City standards, for either base material or
concrete.,
soncret , is 25,903 linear feet, approximately % of the total sidewalk installed in the referenced
subdivisions. The PWD reviewed the sidewalk comprising this total to identify areas where absolute
lu.te
replacement is called for and other areas where conditional acceptance may be a tified. The opinion of
staff is that any area where less than two inches of crushed gravel base is present or any area where
concrete thickness is less than three and one half inches is completely unacceptable and should b
replaced. These values reflect that the City has in the past accepted sidewalks s constructed to .MDT
standards which have various thicknesses of granular base but no less than 2 inches thick. Also, local
constructors have occasionally used standard construction grade 2 X 4s for sidewalk concrete forms. The
-industry standard dimension ofth'is lumber is .1 1/2 inches X 3 1/2 inches rather than a true 2 inch X 4 inch
dimension.
Applying these criteria, PVVID staff has concluded that a total of 7,241 LF of sidewalk fails to
meet City standards, An additional 425 LF in Three Mile Subdivision raises this to 7,666 L . This
s idewalk should be replaced. The replacement will affect approximately 37 households adjacent to the
.,ork sites.
The remaining 18,662 LF of sidewalk also fails to fully meet City standards, either for base
material or concrete thickness, but to a lesser degree than the minimums outlined abo r.: - This sidewalk
has a value even though it Tees not meet City standards. However, present City standards do not provide
for acceptance of substandard items under any circumstance. No .etbeless, it would be desirable to
identify a means to measure the value of these sidewalks if left in service rather than to replace them, with
the associated adverse impacts to adjacent properties. PWD staff has considered this problem and
identified a potential solution. This is outlined In. the .Assistant City Englneer,s attached memo.
The proposed solution is to establish a. structural value for the City's standard sidewalk. This
value is developed around industry standard structural values for the concrete and aggregate base
materials used in sidewalk construction. These structural values were obtained from widely used
A.ASI-ITO and.American Concrete Pavement Association design publications. With the structural value of
the City standard sidewalk at 1 % we propose to measure the various thicknesses of materials in place
and compare theca to the City standard. Once these structural numbers of the.Installed sidewalks are
known wn we can determine the structural value, measured in percent, of the .installed sidewalk against the
City standard. Tabulations of various combinations of base material and concrete have been assembled
and are shown in the attachment. We believe -using this "relative structural value"' approach is a
reasonable method for determining the worth of a sidewalk that does not fully measure up to City
standards, but does not warrant removal and replacement.
Included -in the memo is a tabulation of relative deficiency for the subdivisions in question. It
shows that the range of variation for installed sidewalks is 6.76% to 1 . % less than the standard City
sidewalk. we believe this is a reasonable reflection of their reduced value to the City. we see two options
for reconciling this loss of value.
In order to make up for this lost value, the City could demand a significantly extended warranty.
However, the logistical problems of this option were outlined in previous discussions, and nothing has
occurred since to make acquiring a bondby the developer, or administering extended non-standard
warranties less problematic. An extended warranter does not provide the City tangible compensation for
the reduced value ofthe sidewalk and does not address potential future costs to replace sidewalks that fail
prematurely.
The second option is to obtain a value payn e t from the developer equal to the reduction in value
f the substandard sidewalk. This value payment in lieu of replacement would provide the City a cash
reserve against premature failures. we recommend this value payment he calculated uniformly for each
deficient area. we recommend it be determined using the annual City Sidewalk Construction bid rates,
rather than the individual developer/contractor rates, This rate would be multiplied by the linear feet of
deficient sidewalk and the relative deficiency expressed in percent. This method will ensure each value
payment .is calculated with the same metrics for relative structural value deficiency and the Ot 's most
current actual replacement construction cost.
The attachment includes a. complete tabulation of value deficiencies, expressed in percent and
value reductions, expressed. in dollars for the sldewalks m each subdivision. They range from $790.20 t
$20.,275.16 and total $61,671.04. Once collected, these funds should be set aside in a sidewalk
replacement fund to offset future costs to replace sidewalks that fail prematurely. we believe this reflects
a reasonable solution to the current problem that addresses the main concerns outlined in previous
discussions.
The value payment in lieu of replacement appears to be an equitable option for both the developer
and the City. The City receives a combination f sidewalk and cash equal in value to the Cit 's standard
sidewalk. The City is able to offer a reasonable alternative to removing and replacing a sidewalk. The
adjacent property owners are sheltered from the disruption that .replacement would entail, The general
public is sheltered against .future ha ilities from potential premature failure of the sidewalk. The
developer has -no added cost because the contractor's failure to provide the expected compliant sidewalk
should result in the developer reducing the compensation to the contractor by a like amount to the value
payment. If the value payment is unacceptable to the developer then the remaining option is to replace the
sidewalk.
e o 4 .doe
CONCLUSION AND RECOMMENDATION
Staff has identified a reasonable method for evaluating the relative value of eon -standard
sidewalk. It provides protection for the City while assuring the vale of public infrastructure matches
predetermined expectations. Staff further concludes the need for this remedy could have been avoided had
the developers involved not failed in their responsibility to closely .monitor the performance of their
contractors to assure compliance with their contractual obligations.
Staff recommends adoption of this remedy in lieu of outright replacement of non-standard
sidewalks that can potentially provide a reasonable level of service with minimum future risk to the City.
Staff further reeornmends this be adopted without seeking concurrence from those parties who .have
contributed to creating the problem.
memo0442005.doc
u i
City of Kalispell Public Works
N n- Post � 1 , Kalispell, Mona 90-1 - Telephone (406)758-7720, Fax (406)758-7831w:
MEMORANDUM
September 29, 2005
Jim Hansz, , ., Public Works Director/City Engineer
From: Frank Castles, P.E , Assistant City Engineer
Subdivision Sidewalk Connection Quality
Ached is the Analysis of Sidewalk and Base Constnuction which describes the
rationale behind assigning value to sidewalks not constructed in accordance with the
current standards. Included in the analysis is a table depicting the "score' of the
combinations of acceptable base and concrete thickness*
Also ached is the Subdivision Sidewalk Analysis based on the sidewalks cored In each
subdivision, The per cent f A re score is only applied to the sidewalks meeting the
minimum r*ee of 2" thickness '" minus crushed 2 1" thickness of pit run) base
and/or 3 1" thickness of concrete.
The sidewalk replacement fee is based on the current bid price for city sidewalk
replacement of $30.00 per foot of 5 foot wide sidewalk meeting the current thickness
standard for base and concrete.
The sidewalks at Discovery Development Center (75 Glenwood) and Wesiview Business
Center (off North Meridian Road) were cored and found to meet the city standards for
base and concrete thickness.
ANALYSIS OF SIDEWALK AND BASE CONSTRUCTION
The structural number N a particular pavement action Is the summation of the lager
thicknesses multiplied by the respective layer coeftent. The concept of layer coefficients was
developed during the road test conducted by the American Assodation of State Highway Officials
(AASHO),, to account for all of the materials and layers in a pavement structure.
Research of the AA HTO --- QW-e fgr,,Qg5.ign pf egavemgnt Structures and the American Concrete
Pavement Publication ."Equivalency Chart for concrete and Asphalt Pavements" was the source
for the following list:
Material Layer Coefficient
(per inch)
Concrete 0.50
Crushed Gravel 0.14
Gravel Base 0.10
The City of Kalispell Standards for Design and Construction 2005, require four inches of concrete
for the sidewalk and six ides o -Y4" minus crushed gravel for the sidewalk base material. The
SN of this combination is calculated asfollows:
" Concrete X #50 ...rr. r. ti Y i A d Y* r► U' #
00
f' crushed Gravel X 0. 144. . =
Total 2.84
Are equivalent gravel base is calculated as: " X 0.(crushed gravel). 10 (gravel
base) = ,40"
The concrete contributes 70.42% of the total SN and the crushed gravel contributes 29.58% of
the total SN for the required sidewalk section. A `scoring' methodology is calculated as follows:
. " concrete = 17.61% per inch thickness of concrete
. " crushed gravel = 4.93% per inch thickness of crushed graved
. a '# gravel base = 3.52% per inch thickness of gravel base
A crushed graved base of less than 2" is unacceptable.
A gravel base of less than 2 1 " is unacceptable ( 2" X 0.1 . 10 f SN's for crushed vs
graved base).
This scoring method allows different combinations of mricrete and base material to be compared
against the standard which has a value o %.
CONCRETE THICKNESS - CRUSHED GRAVEL BASE THICKNESS SCORING CHART
CONCRETE THICKNESS " 1 vw 5
10 1 2it Ott 112
rr
CRUSHED
RAVEL
BASE
THICKNESS
1 2"
1+
1+
+
1+
1+
93,69
0+
+
1 +
1 +
95.09
86.29
1 "
1 +
1 +
1 0+
.5 1
87.70
78.90
r
1 +
1 0+
1 +
94-04
95.23.
21 r
1 +
1 +
1 +
1.58
82-77
73.97
A CRUSHED `GRAVES. BASE THICKNESS F LESS THAN " SCORES 1 V I� ENTIRE
1 AREA AND THAT AREA SHALL BE REPLACED
A CONCRETE THICKN ESS OF LESS THAN " SCORES A ' ' FOR THE ENTIRE AREA
AND THAT AREA SHALL BE REPLACED
CONCRETE THICKNESS — GRAVEL BASE THICKNESS SCORING CHAR`
CONCRETE THICKNESS 6
to S 1 r, 5 fl 1 11 3 1 It
GRAVEL
BASE
THICKNESS
710
1 +
1 +
1 +
100+
95.09
86.28
1 #F
+
1 +
1 +
1 +
93.32
84.52
'#
+
1 +
1 +
1 +
91.56
82.76
1 "
+
1 +
+
98.61
S{`
1+
1+
+
96.85
88.04
79-24
1 +
1 +
1 +
95.09
W2877-48
1 +
1 +
1 +
93.3,E
84s52
7.7
11ai
1 +
1 +
1 +
91.57
82.763.
,#
1+
1+
98.61
89-81
81.0072.20
1 +
1 + J6
96.85
88.057.
T2
7 .E
A GRAVEL BASE THICKNESS OF LESS THAN 2 1 " SCORES A r ' FOR THE ENTIRE
AREA AND FRAY AREA SHAD. BE REPLACED
CONCRETE TH IC KN ESS OF LESS THAN 1 " SCORES A ' ' FOR THE ENTIRE AREA
AND THAT AREA SHALL BE REPLACED
SUBDIVISION SIDEWALK ANALYSIS
9129/2005 (UPDATED 12/6/05
SUBDIVISION
ASH LEY PARK, PHASE 7
BLUE HERON, PHASE I & 2
EMPIRE ESTATES, PHASE 1, 2 & 3
GLACIER VILLAGE GREENS, PHASE 17 & 20
LEISURE HEIGHTS, PHASE 1 & 2
STRATFORD VILLAGE, PHASE 3
SUNNYSIDE, PHASE 2
THREE MILE SUBDIVISION*
LINEAR FEET
LINEAR FEET OF
LINEAR FEET
RESIDENCES
LINEAR FEET OF
PER CENT
SIDEWALK
TOTAL SIDEWALK
SIDEWALK MEETING
SIDEWALK TO
EFFECTED
SIDEWALK WITH LESS
FAILURE
REPLACEMENT
100% SCORE
REMOVE AND REPLACE
THAN 100% SCORE
SCORE
FEE
3,155
300
630
1
2,225
19.58
$13,069.6S
4,828
11500
560
8
2,768
6.76
$5,613.50
13,630
5,700
1,475
13
6,455
10.47
$20,275,16
2,365
2,065
0
0
300
8.78
$790.20
8,230
1,800
3,520
4
2,910
11.56
$10,091.80
4,760
1,200
816
8
2,744
10-34
$8,511,89
3,600
2,100
240
7
1,260
8.78
$3,31&84
*THE SIDEWALKS WITHIN THREE MILE SUBDIVISION ARE CURRENTLY BEING INSTALLED BY THE BUILDER
AS EACH RESIDENCE IS COMPLETED, AT THE PRESENT TIME APPROXIMATELY 425 FEET OF SIDEWALK
DO NOT HAVE THE MINIMUM BASE AND/OR MINIMUM CONCRETE THICKNESS. RECOMMEND THAT NO BOND
BE RELEASED UNTIL A CORE AT EACH ADDRESS (OR LOTS CONTAINS A MINIMUM OF 6" THICK 3/4" MINUS CRUSHED
STONE AND A MINIMUM THICKNESS OF 4" OF CONCRETE FOR THE SIDEWALK,