HomeMy WebLinkAboutCAPITAL IMPROVEMENTS - 01/27/1983 - February 4, 1983
MINUTES
CAPITAL IMPROVEMENTS COMMITTEE
Thursday, Jan. 27, 1983
MEMBERS PRESENT: STAFF PRESENT:
Mike Tosto - Committee Chairman Gary Parrin, Asst. Village Manager
Steve Uhlarik - Committee Member George Coney, Finance Director
Ray Peterson, Village Engineer
MEMBERS ABSENT: Mark Toberman, Ass't. Vill. Engineer
Ron Chernick - Committee Member
OTHERS PRESENT:
Ed Hauser, Village Trustee
Joe Bosslet, Village Trustee
Richard Nogaj , RJN Environmental Assoc.
Richard Nelson, RJN Environmental Assoc.
Chiman Patel, RJN Environmental Assoc.
The meeting was called to order by Mike Tosto at 7:05 p.m. in the
Trustees Conference Room of the Elk Grove Village Municipal Building. The
purpose of the meeting was to discuss the lack of flooding in the Industrial
Park on December 23, 1982, when severe flooding did occur along creeks and
rivers in the Chicagoland area. (The concern relates to the proposed drain-
age project that the Village is trying to establish in a portion of the
Industrial Park to resolve drainage and flooding problems) .
A report on the facts of the December 2, 1983 storm was distributed
by RJN at the meeting. Although the report shows approximately 3 inches of
rain fell in this area over a 24 hour period, the peak intensity did not
exceed 0.27 inches in any one-half hour period, or about one-quarter the
intensity of the 30 minute, 2 year storm on which the RJN study is based.
The existing system in this area, for the most part, was able to handle
the rainfall of December 2, 1982 because of the lack of high rainfall
intensity.
Unlike Salt Creek within the Village, which accepts water from
many drainage basins upstream (and flooded because of the large volume of
water that fell and not because of the high intensity) , the two basins in
the industrial study area do not receive water from any other basins. As
such, the volume of water falling within the basins was not critical.
next page please. . .
Capital Improvements Committee Meeting
Page 2
February 4, 1983
The point of possibly phasing this drainage project was discussed.
It was determined that phasing is possible in the following order:
1) Provide detention and replace critical undersized
culvert with adequately sized culverts,
2) Clean the ditches once, or provide storm sewer,
3) Provide regular maintenance of the system.
It was the consensus of the Board members present, that although the
December 2nd rain certainly did not help in trying to establish the project,
the Village should continue to work with the Industrial community in resol-
ving the problems that do exist, and keep the communication lines open.
i
Respectf ly Submitted
RLP.pp
cc: President and Board
Village Manager, Ass't. Vill. Manager, Finance Director, Director of
Public Works, Village Engineer, Ass't. Village Engineer
February 4, 1983
TO: Mike Tosto, Chairman
Capital Improvement Committee
FROM: '/g� �} .�c�i E'�c...�s`�
RECy L. Pe son, Village Engineer
SUBJECT: SUMMARY OF CAPITAL IMPROVEMENT COMMITTEE
MEETING OF JANUARY 27, 1983
The Committee along with several Board members and member of
staff met on Thursday, January 27, 1983 with RJN Environmental, our
Industrial Ditch consultant for the proposed Special Service Area.
The purpose of the meeting was for the Village to understand the
reasons for the lack of flooding in this part of the park before
the Public Hearing which was last Tuesday night.
Those present at the meeting were understandably concerned
that so much flooding occurred throughout the Chicagoland area, and
yet, except for some localized flooding on Nicholas and near Elmhurst
Road, the industrial park experienced no exceptional problems. By
the conclusion of the meeting, I believe everyone had a basic under-
standing of the reasons.
The consensus of those Board members present was that the
Village should try to keep the basic project alive and maintain commun-
ication with the industrial owners because we know problems do exist
and, that they will get worse if nothing is done.
RLP:pp
RESOLUTION OF STORM EVENTS
THAT OCCURRED IN DECEMBER, 1982
FOR THE
VILLAGE OF ELK GROVE VILLAGE
COOK COUNTY, ILLINOIS
BY
RJN ENVIRONMENTAL ASSOCIATES, INC
CONSULTING ENGINEERS
WHEATON, ILLINOIS
JANUARY, 1983
Introduction
The rainfall occurring during December, 1982 resulted in
flooding along creeks and rivers in northeastern Illinois .
According to the Illinois State Water Resource Department the
high water level which occurred in Salt Creek was approximately
at the 10-year flood stage at the junction of Lake Street and
Salt Creek and the water level in Silver Creek at Irving Park
Road was approximately at the 25-year flood stage . Yet, with
flood levels observed in creeks and rivers , the Eastern
Industrial Area of the Village of Elk Grove Village was
apparently minimally effected. The "Flood Control Study" for
the Eastern Industrial Area, completed by RJN Environmental
Associates, Inc . January, 1982, indicated that the storm ditches
of the Eastern Industrial Area do not have adequate hydraulic
capacity to transport storm flows for even a 6-month, 30-minute
duration storm event. This report will reconcile observed
conditions with predicted conditions and explain, in further
detail , rainfall recurrence interval for a particular year
storm.
The Design Storm
Predictions of stormwater runoff and sizing of storm sewers
or drainage structures are dependent on rainfall intensity,
duration, frequency, distribution pattern of rainfall , soil ,
moisture, and topographic features . The proper storm duration
to use in design is referred to as the critical duration. Since
the predicted peak flow from a basin will vary with duration of
rainfall , critical duration will be that which causes the
-1-
a
greatest peak flow. Historically the time of concentration for
a basin ( in other words the travel time from the most remote
point in a basin to the basin outlet) has been used as critical
duration. For the Eastern Industrial Area of the Village of Elk
Grove Village the critical duration was determined to be
approximately 30 minutes . This short critical duration is due,
in part, to the high percentage of paved and roofed surfaces
which result in rapid storm runoff. Because of this , short
intense storm events will produce a higher peak stormwater flow
and consequently more localized flooding than longer duration
low intensity storm events of a similar recurrence interval .
For the Eastern Industrial Area, 2-year , 30-minute duration
storm protection was selected . Alternatives presented in the
Flood Control Report were analyzed on this basis . This level of
storm protection was selected since it provided a reasonable
level of storm protection at a minimum incremental cost. To
provide greater than 2-year, 30-minute duration storm protection
would require additional retention sites . Such an alternative
would be different in concept (not just sizing of pipes and
ditches) than those presented in the Flood Control Report and
would include purchase of costly improvable real estate . The
2-year storm protection level would provide for free flow of
stormwater without surcharge at the design storm event .
Additional protection may be provided during more intense storm
events when surcharge of the system would occur .
A 2-year storm would have a rainfall intensity which would ,
on the average , be equalled or exceeded only once in two years .
This does not imply that it will only occur once every two
years, or having occurred, will not happen again for two years .
By designing the storm drainage systems for 2-year protection,
the number of flooding events, on the average, would be 50 in
100 years . The cost of providing additional capacity increases
with greater storm protection levels . The incremental cost per
flooding event for storm drainage events in the Eastern
Industrial Area is shown in Table 1 .
-2-
December , 1982 Rainfall Analysis
The rainfall events of December 2 , 1982 and December 24 ,
1982 resulted in 10-year to 25-year flood stages in local creeks
and rivers. Severe flooding , however, did not occur in the
Eastern Industrial Area. The rainfall distribution for the
December 2 storm event as monitored at Hanover Park and
Glenview, is shown in Table 2. and Table 3 . A location map
showing the monitoring points relative to Village of Elk Grove
Village is shown on Exhibit 1 . The maximum peak 30-minute
duration rainfall , as monitored at Glenview, occurred between
5 :00 pm and 5 :30 pm and was 0.28 inches of rainfall . This
quantity of rainfall is approximately one-fourth of the peak
2-year , 30-minute duration design rainfall of 1 .07 inches in 30
minutes . The 0. 28 inches of rainfall is less than a 6-month,
30-minute rainfall event and would not be expected to cause
significant flooding in the Eastern Industrial Area.
Nevertheless, site inspections at approximately 4: 30 pm December
2, 1982 by RJN Environmental Associates, Inc . personnel found
Nicholas Boulevard ditches full of stormwater and within inches
of the road pavement indicating that even at less than 6-month
frequency flooding conditions were being approached in the
Eastern Industrial Area .
The rainfall distribution as monitored at Hanover Park is
shown for the December 24, 1982 storm event in Table 4. The
peak 30-minute duration rainfall occurred between 8 :00 pm and
8 :30 pm and was 0. 20 inches of rainfall . This quantity of
rainfall is approximately one-fifth of the peak 2 year,
30-minute duration design rainfall of 1 .07 inches in 30 minutes .
The 0. 20 inches of rainfall is less than a 6-month, 30-minute
rainfall event and would not be expected to cause significant
flooding in the Eastern Industrial Area. Rainfall patterns of
the design 2-year rainfall event and the monitored rainfall
events occurring in December are shown in Exhibit 2 . This
exhibit shows the monitored events to be less than the design
storm event .
-3-
In summary, peak flow and localized flooding in the Eastern
Industrial Area will result from intense short duration storm
events . Because the intensity of peak 30 minute rainfalls of
December 2 and December 24, 1982 were less than 6 month rainfall
events, flooding in the Eastern Industrial Area did not occur .
Large areas , however, such as creek and river drainage basins
did develop peak conditions because of long duration storm
events . The cumulative effects of individual storm events in
December, 1982 resulted in 10 year and 25 year flood stages .
The longer critical rainfall durations of rivers and creek
drainage basins is the reason for the apparent inconsistencies
observed between little flooding in the Eastern Industrial Area
and flood stages reached in local creeks and rivers .
-4-
Table 1
Incremental Cost Per Flooding Event
Eastern Industrial Area
Village of Elk Grove Village
Incremental
Flooding Present Cost Per
Events in Worth of Flooding Event
Storm Protection 100 Years Improvementsl/ Reduction
6-month 200 - -
(Current Protection)
2-Year 50 5 .618 $37, 453
5-Year 20 7. 150 $61 , 066
10-Year 10 8. 324 $87 , 400
l/ Based on Alternative 5 from Table III-8 of the Flood Control
Study Report.
-5-
Table 2
RAINFALL DISTRIBUTION
MONITORED AT MSDGC HANOVER PARK WATER RECLAMATION PLANT
DECEMBER 2, 1982 STORM EVENT
Rainfall Rainfall
Time (Inches) Time (Inches)
12 :30 am - 1: 00 am 0. 00 12 :30 pm - 1 : 00 pm 0 . 01
1: 00 am - 1: 30 am 0. 07 1 : 00 pm - 1 :30 pm 0 . 02
1:30 am - 2: 00 am 0. 00 1 : 30 pm - 2 : 00 pm 0 . 00
2:00 am - 2 :30 am 0. 00 2 :00 pm - 2 :30 pm 0 . 00
2:30 am - 3: 00 am 0. 16 2 :30 pm - 3 : 00 pm 0. 00
3 : 00 am - 3 :30 am 0. 00 3 :00 pm - 3 :30 pm 0.01
3:30 am - 4 : 00 am 0. 00 3 :30 pm - 4 : 00 pm 0.27
4 : 00 am - 4 : 30 am 0.02 4 :00 pm - 4 :30 pm 0.25
4 :30 am - 5:00 am 0. 18 4 :30 pm - 5: 00 pm 0 .12
5 : 00 am - 5:30 am 0.12 5 :00 pm - 5 :30 pm 0.11
5:30 am - 6: 00 am 0. 02 5:30 pm - 6:00 pm 0. 07
6:00 am - 6 :30 am 0. 00 6 :00 pm - 6 :30 pm 0 .10
6:30 am - 7 : 00 am 0. 00 6 :30 pm - 7 : 00 pm 0. 05
7: 00 am - 7 :30 am 0. 02 7 :00 pm - 7 :30 pm 0 .13
7:30 am - 8 : 00 am 0. 00 7 :30 Fun - 8 : 00 pm 0.10
8:00 am - 8:30 am 0.01 8 : 00 pm - 8 :30 pm 0.12
8 :30 am - 9: 00 am 0.01 8 :30 pm - 9:00 pm 0.14
9: 00 am - 9: 30 am 0.12 9 :00 pm - 9 :30 pm 0.15
9:30 am - 10: 00 am 0. 20 9:30 pm - 10:00 pm 0. 07
10: 00 am - 10: 30 am 0. 01 10 : 00 pm - 10. 30 pm 0 . 01
10: 30 am - 11: 00 am 0.14 10 :30 pm - 11 : 00 pm 0. 00
11: 00 am - 11:30 am - 0. 09 11 : 00 pm - 11 :30 pm 0. 00
11 :30 am - 12 :00 am 0. 02 11: 30 pm - 12:00 pm 0. 00
12: 00 am - 12: 30 pm 0.02 12 :00 pm - 12:30 am 0. 00
Total Rainfall = 2. 94 inches
Table 3
RAINFALL DISTRIBUTION
MONITORED AT GLENVIEW
DECEMBER 2, 1982 STORM EVENT
Rainfall Rainfall
Time (Inches) Time (Inches)
2 : 30 am - 3 : 00 am 0. 00 2 : 30 pm - 3 : 00 pm 0 . 00
3 : 00 am - 3 :30 am 0. 00 3 : 00 pm - 3 : 30 pm 0 . 00
3 : 30 am - 4 : 00 am 0. 00 3 : 30 pm - 4 : 00 pm 0. 02
4 : 00 am - 4 : 30 am 0. 05 4 : 00 pm - 4 :30 pm 0. 03
4 : 30 am - 5: 00 am 0. 00 4 : 30 pm - 5 : 00 pm 0. 18
5 : 00 am - 5: 30 am 0. 00 5 : 00 pm - 5 : 30 pm 0. 28
5 : 30 am - 6 : 00 am 0.12 5 :30 pm - 6 : 00 pm 0. 09
6 : 00 am - 6 : 30 am 0. 01 6 :00 pm - 6 :30 pm 0 .06
6 :30 am - 7 : 00 am 0. 01 6 : 30 pm - 7 : 00 pm 0 . 04
7 : 00 am - 7 :30 am 0. 02 7 : 00 pm - 7 :30 pm 0 .05
7 : 30 am - 8 : 00 am 0. 01 7 :30 pm - 8 : 00 pm 0. 00
8 : 00 am - 8 : 30 am 0. 00 8 : 00 pm - 8 :30 pm 0 .10
8 :30 am - 9 : 00 am 0. 00 8 :30 pm - 9 : 00 pm 0 .13
9 : 00 am - 9:30 am 0. 00 9 :00 pm - 9 :30 pm 0 .16
9 : 30 am - 10:00 am 0. 02 9 :30 pm - 10: 00 pm 0 .19
10: 00 am - 10 :30 am 0.00 10 : 00 pm - 10 :30 pm 0 .12
10: 30 am - 11: 00 am 0.02 10 :30 pm - 11 :00 pm 0 .09
11: 00 am - 11: 30 am 0. 09 11 : 00 pm - 11 : 30 pm 0 . 04
11 : 30 am - 12: 00 am 0. 14 11: 30 pm - 12: 00 pm 0. 09
12 : 00 am - 12 :30 pm 0.10 12 : 00 pm - 12:30 am 0 . 04
12: 30 pm - 1:00 pm 0. 05 12 : 30 am - 1 : 00 am 0 . 03
1 : 00 pm - 1: 30 pm - 0 . 02 1: 00 am - 1:30 am 0 . 01
1:30 pm - 2 : 00 pm 0. 01 1:30 am - 2 :00 am 0 . 01
2 : 00 pm - -:30 pm 0. 00 2 : 00 am - 2 : 30 am 0. 00 .
Total Rainfall = 2 .42 Inches
Table 4
RAINFALL DISTRIBUTION
MONITORED AT MSDGC HANOVER PARK WATER RECLAMATION PLANT
DECEMBER 24, 1982 STORM EVENT
Rainfall Rainfall
Time (Inches) Time (Inches)
12 : 00 am - 12 :30 am 0. 00 12 : 00 pm - 12 :30 pm 0 . 00
12:30 am - 1:00 am 0.00 12: 30 pm - 1:00 pm 0. 00
1 :00 am - 1: 30 am 0. 00 1: 00 pm - 1 :30 pm 0 . 00
1:30 am - 2: 00 am 0. 00 1 :30 pm - 2 : 00 pm 0. 00
2: 00 am - 2 :30 am 0. 00 2: 00 pm - 2 :30 pm 0. 00
2:30 am - 3 :00 am 0. 00 2 :30 pm - 3 : 00 pm 0. 00
3 : 00 am - 3: 30 am 0. 00 3 : 00 pm - 3 :30 pm 0 . 00
3 :30 am - 4 : 00 am 0. 00 3 :30 pm - 4 :00 pm 0. 00
4 : 00 am - 4 :30 am 0. 02 4 : 00 pm - 4 :30 pm 0 . 00
4 : 30 am - 5 : 00 am 0. 01 4 :30 pm - 5 : 00 pm 0 . 00
5:00 am - 5 :30 am 0.02 5 : 00 pm - 5 :30 pm 0 . 00
5 :30 am - 6 : 00 am 0. 00 5 :30 pm - 6 :00 pm 0 .00
6 : 00 am - 6 :30 am 0.00 6 : 00 pm - 6 :30 pm 0. 00
6: 30 am - 7 : 00 am 0. 00 6 :30 pm - 7 : 00 pm 0 . 01
7: 00 am - 7:30 am 0. 01 7 :00 pm - 7 :30 pm 0. 02
7 :30 am - 8 : 00 am 0. 01 7 :30 pm - 8 : 00 pm 0.15
8 :00 am - 8 :30 am 0. 00 8 : 00 pm - 8 :30 pm 0. 20
8 :30 am - 9: 00 am 0. 00 8 :30 pm - 9 :00 pm 0. 21
9: 00 am - 9: 30 am 0. 00 9 :00 pm - 9 :30 pm 0. 02
9: 30 am - 10: 00 am 0. 00 9 : 30 pm - 10: 00 pm 0. 00
10: 00 am - 10: 30 am 0. 00 10 : 00 pm - 10 :30 pm 0 . 00
10:30 am - 11: 00 am 0. 00 10 : 30 pm - 11 : 00 pm 0. 00
11: 00 am - 11:30 am 0. 00 11 : 00 pm - 11 :30 pm 0. 00
11: 30 am - 12: 00 pm 0. 00 11 :30 pm - 12 : 00 am 0 . 00
Total Rainfall = 0. 67 Inches
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RJN Environmental Associates, Inc. EXHIBIT I
0.20 /
1 1
0.,6 I 1
RAINFALL FOR
I ' 2 YEAR STORM - ILLUOAS
TOTAL RAIN 'LOT INCHES
0.16 I 1
I 1
6LENV/EW
0./4 I 1 RAINFALL ON DEC.2,1982
1 5:00 PM TO 5:30 PM
I TOTAL RAIN-0.28 INCHES
N 1 d
r I
0.12
fy
Z 0do
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I O.OB I NAMOVEN PMK \ I I NAAWVER PAgA'
RAINFALL ON RAINFALL ON DEC.2,1982
W DEC.2,1982 \ f 3:30 PM TO 4:00 PM
it I 4:00 PM TO 4:30 PM I TOTAL RAIN-0.27 INCHES
L) TOTAL RAIN-0.25 INCHES\
0.06 \ I I
I RAINFALL ON \ 1
DEC.24, 1982
fax
0.04 TOTAL RAIN-0.21 INCHES • 41, • !
002
0.00
0 2 4 6 B /0 /2 14 16 /6 20 22 24 26 26 30
TIME DURING PEAK 30- MINUTE DURATION RAINFALL (minutes)
COMPARISON OF
RAINFALL EVENTS
M Environmental Associates, Inc. EXHIBIT 2
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15-MINUTE, 2-YEAR RAINFALL 30-MINUTE, 2-YEAR RAINFALL
Figure 12. 2-year frequency of 6-county rainfall
33
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15-MINUTE, 6-MONTH RAINFALL 30-MINUTE, 6-MONTH RAINFALL
Figure 10. 0.5-year frequency of 6-county rainfall
27
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_ Kilometers
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12-HOUR, 2-YEAR RAINFALL 24-HOUR, 2-YEAR RAINFALL
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Figure 12 (Concluded)
35
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RAINFALL PER 2 YEAR II
0.8 30 MINUTE DURATION II
DESIGN STORM
TOTAL RAIN - 1.07 I
r INCHES I
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DECEMBER 2, 1982
0.4 I 24 HOUR RAINFALL
TOTAL RAIN-2.94
INCHES
0.5
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I I
0.0
0 / 2 4 6 8 /0 /2 /4 /6 /8 20 22 24 26 28 30
TIME (hours)
TOTAL RAINFALL
DISTRIBUTION
RJN Environmental Associates, Inc. EXHIBIT 3