HomeMy WebLinkAboutCC 10 EL MODENA IMPROV 6-18-90DATE:
TO:
FROM:
JUNE 11, 1990
WILLIAM HUSTON, CITY MANAGER
CONSENT CALENDAR NO. 10
6/18/90
Inter - Com
PUBLIC WORKS DEPARTMENT/ENGINEERING DIVISION
SUBJECT: NEGATIVE DECLARATION - EL MODENA/IRVINE CHANNEL IMPROVEMENTS
RECOMMENDATION:
That the Tustin City Council pass and adopt a resolution certifying the
Final Negative Declaration as adequate for the El Modena/Irvine Channel
Improvements including the required findings pursuant to the California
Environmental Quality Act.
BACKGROUND:
The subject project is being constructed by the City of Tustin as a
mitigation measure to the development of the two new Auto Center lots
within the old Auto Center Retarding Basin parcel. These flood control
improvements consist of 830 L.F. of vertical wall concrete lined channel
between the Santa Ana (I-5) freeway and Michelle Drive along the E1
Modena/Irvine Channel alignment. Funding for this project has been
appropriated in the current 1989-90 Capital Improvement Budget.
As the lead agency on this project, the City is required to complete an
Initial study on the project and prepare a Negative Declaration for the
City Council's final action.
DISCUSSION:
Staff has prepared the Initial Study (copy attached) and found that the
proposed project could have a significant effect on the environment, but
there will not be a significant effect in this case because the
mitigation measures described in the study have been added to the
project. A Negative Declaration for the project has been prepared and
is attached as a part of this report for the City Council's information.
The attached City Council resolution certifies the Final Negative
Declaration as adequate for the proposed E1 Modena/Irvine Channel
Improvements including the required findings pursuant to the California
Environmental Quality Act. These findings are listed under Section I A-
D in the attached resolution.
Staff recommends that the City Council pass and adopt this resolution at
their meeting of June 18, 1990.
Bob Ledendecker
Director of Public Works/City Engineer
Attach.
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RESOLUTION NO. 90-69
A RESOLUTION OF THE CITY COUNCIL OF THE
CITY OF TUSTIN, CALIFORNIA CERTIFYING THE
FINAL NEGATIVE DECLARATION AS ADEQUATE FOR
THE EL MODENA/IRVINE CHANNEL IMPROVEMENTS
INCLUDING REQUIRED FINDINGS PURSUANT TO THE
CALIFORNIA ENVIRONMENTAL QUALITY ACT.
The City Council of the City of Tustin does hereby resolve
las follows:
I. The City Council finds and determines as follows:
A. The El Modena/Irvine Channel Improvement Project is
considered a "project" pursuant to the terms of the
California Environmental Quality Act.
B. A Negative Declaration has been prepared for this
project and has been distributed for public review.
C. Whereby, the City Council of the City of Tustin has
considered evidence presented by the Public Works
Department and other interested parties with respect
to the subject Negative Declaration.
D. The City Council has evaluated the proposed final
Negative Declaration and determined it to be
adequate and complete.
II. A Final Negative Declaration has been completed in
compliance with CEQA and State guidelines. The City
Council, having the approval authority over the El
Modena/Irvine Channel improvements between the Santa Ana
Freeway and Michelle Drive and the Public Works Department
having final approval authority over the engineering design
and has received and considered the information contained
in the Negative Declaration prior to approving the proposed
project and found that it adequately discussed the environ-
mental effects of the proposed project.
On the basis of the initial study and comments received
during the public review process, the City Council has
found that although the proposed projects could have a
significant effect on the environment, there will not be a
significant effect on it in this case because mitigation
measures identified in the Negative Declaration have been
incorporated into the projects which mitigate any potential
significant environmental effects to a point where clearly
no significant effect would occur and are identified in
Exhibit A to the attached Negative Declaration and initial
study incorporated herein by reference.
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PASSED AND ADOPTED at a regular meeting of the Tustin City
Council held on the 18th day of June, 1990.
Richard B. Edgar,Mayor
Attest:
Valerie Whiteman
Chief Deputy City Clerk
RESOLUTION CERTIFICATION
STATE OF CALIFORNIA )
COUNTY OF ORANGE ) SS
CITY OF TUSTIN )
RESOLUTION NO. 90-69
MARY E. WYNN, City Clerk and ex -officio Clerk of the City
Council of the City of Tustin, California, does hereby certify
that the whole number of the members of the City Council of the
City of Tustin is four; that the above and foregoing Resolution
No. 90-69 was duly and regularly introduced, passed and adopted
at a regular meeting of the City Council held on the 18th day of
June, 1990, by the following vote:
COUNCILMEMBER AYES:
COUNCILMEMBER NOES:
COUNCILMEMBER ABSTAINED:
COUNCILMEMBER ABSENT:
Valerie Whiteman, Chief Deputy City Clerk
for Mary E. Wynn, City Clerk
NEGA'I .VE DECLARATI .V
CITY OF TUSTIN �A 82680
vs'V 300 CENTENNIAL WAY, TUSTIN,
File No. 1208.5
Project Title: E1 Modena -Irvine Channel Improvements
Project Location: Downstream of the Santa Ana Fwy. Bridge to downstream
of the Mitchelle Drive Bridge in Irvine. .
Project Description: Improvements to 830 feet of channel length at the
50 foot rectangular concrete channel.
Project Proponent: City.of Tustin
Contact Person: Mr. Bob Ledendecker
Telephone: .3�¢—�gy° Ext..2FI
The Community Development Department has conducted an initial study
yfor regardthe
above project in accordance wtEnvi the. 1 City oQu 1 i ty Act, procedures and on the basis of
ing
implementation of the California
that study hereby find:
That there is no substantial evidence that the project may have a
Dsignificant effect on the environment.
That potential
significant
affects were
identified, but revisions have
to by the applicant that
a
been included in the project plans and
mitigate the affects
agreed
ta n whereclearly
rto
would avoid or
significant effects would
occur. Said
oo and
revisions are
hereby made a
part of this
Negative Declaration.
Therefore, the preparation of an Environmental Impact Report is not required.
The initial study which provides the basis for this determination is on
file at the Community Development Department, City of Tustin. The public
is invited to comment on the appropriateness of hes Negative
notice Declaration fa
during the review period, which begins with public c
Negative Declaration and extends for seven calendar days. Upon review by
the Community Development Director, this review period may be extended if
deemed necessary.
REVIEW PERIOD ENDS 4:30 p. m. 'on June 18, 1990
DATED: May 23, 1990
Bob Ledenclecker
Director of Public Works/City Engineer
INITIAL STUDY
NAME OF PROJECT
El Modena -Irvine Channel Improvements, OCEMA Facility No. F07, Santa Ana Freeway to Michelle Drive
PROJECT DESCRHMON
The El Modena -Irvine Channel is a regional flood control facility under the jurisdiction of the Orange County
Environmental Management Agency (Facility No. F07) with a tributary area of 8,210 acres at the Santa Ana
Freeway (I-5). The existing earthen trapezoidal channel facility was originally constructed in 1951 with the
County Flood Control bond funds. Due to the inadequacies of the existing flood control facilities to provide
100 -year flood protection, it was necessary to construct flood control improvements with the most recent
development on the adjacent East Tustin sites. The most recent channel improvements in the area of interest
along the El Modena -Irvine channel are located in the reach from the Santa Ana Freeway to Browning Avenue
(approximately 5,300 feet). This facility was constructed in 1986 and completed in early 1987 with a construction
cost of 8.8 million dollars. These improvements end at the downstream face of the Santa Ana Freeway bridge
where a reinforced concrete channel transition was constructed to transition the larger ultimate channel section
into the existing downstream earthen channel.
The upstream improvements provide a significant relief from a large portion of the existing flood hazards.
However, the channel system constructed cannot operate at its potential until improvements are implemented
downstream of the Santa Ana Freeway, since it is only one piece of a masterplanned flood control system.
The proposed project considered in this Initial Study consists of channel improvements from downstream of
the Santa Ana Freeway bridge to downstream of the Michelle Drive bridge, a reach of approximately 830 feet
of channel. The proposed project includes improving the existing earthen channel to a concrete rectangular
channel with a 50 foot wide base width. The section through Michelle Drive bridge would consist of a
rectangular concrete section with a 50 foot basewidth. The improvements would also include dropping the
channel invert approximately 2 feet.
ENVIRONMENTAL SETTING
The reach of the EL Modena -Irvine Channel to be improved is an unimproved earthen trapezoidal channel with
a base width of twenty-one feet, side slopes of 1.5:1 and a depth of ten feet. This reach of the channel is part
of the original flood control improvements constructed in 1951 and has not been improved since that time. The
capacity of this existing channel is approximately 3300 cfs or about one-third the required 100 -year conveyance
capacity which is estimated to be 7900 cfs at this location. The land uses adjacent to the reach of the El
Modena -Irvine Channel to be improved by this project is agricultural.
PREPARED FOR
CITY OF TUSTIN
300 Centennial Way
Tustin, California 92680
Contact:Bob Ledendecker
Telephone: (714) 544-8890
PREPARED BY
ROBERT BEIN WILLIAM FROST AND ASSOCIATES
14725 Alton Parkway
Irvine, CA 92714
Contact: Jennifer Langford
Telephone: (714) 855-3661
CITY OF TUSTIN
Community Development Department
ENVIRONMENTAL UNTITIAL STUDY FORM
Lead Agency:
CITY OF TUSTIN
300 Centennial Way
Tustin, California 92680
I. BACKGROUND
1. Name of Project Proponent: City of Tustin
2. Address and Phone Number of Proponent: 300 Centennial Way, Tustin,
California 92680; (714) 676-4101
3. Date Checklist Submitted:
4. Agency Requiring Checklist: City of Tustin
5. Name of Proposal, if applicable: El Modena -Irvine Channel Improvement
(OCEMA Facility No. F07) Santa Ana Freeway to Michelle Drive
II. ENVIRONMENTAL IMPACTS
(Explanations of all "yes" and "maybe" answers are required on attached sheets.)
Yes Maybe No
1. EARTH. Will the proposal result in:
a. Unstable earth conditions or in
changes in geologic substructures? X
b. Disruptions, displacements, compaction
or overcovering of the soil? X
C. Change in topography or ground surface
relief features? X
d. The destruction, covering or
modification of any unique geologic or
physical features? X
e. Any increase in wind or water erosion
of soils, either on or off the site? X
2.
3.
f. Changes in deposition or erosion of
beach sands, or changes in siltation,
deposition or erosion which may modify
the channel of a river or stream or
the bed of the ocean or any bay, inlet
or lake?
g. Exposure of people or property to
geologic hazards such as earthquakes,
landslides, mudslides, ground failure,
or similar hazards?
AIR. Will the proposal result in:
a. Substantial air emissions or
deterioration of ambient air quality?
b. The creation of objectionable odors?
C. Alteration of air movement, moisture, or
temperature, or any change in climate,
either locally or regionally?
WATER. Will the proposal result in:
a. Changes in currents, or the course of
direction of water movements, in either
Marine or fresh waters?
b. Changes in absorption rates, drainage
patterns, or the rate and amount of
surface runoff?
C. Alterations to the course or flow of
flood waters?
d. Change in the amount of surface water
in any water body?
e. Discharge into surface waters, or in
any alteration of surface water
quality, including but not limited to
temperature, dissolved oxygen or
turbidity?
Yes Maybe No
X
X
X
X
X
X
X
X
X
9
5.
f. Alteration of the direction or rate
of flow of ground waters?
g. Change in the quality of ground waters,
either through direct additions or with -
drawls, or through interception of an
aquifer by cuts or excavations?
h. Substantial reduction in the amount of
water otherwise available for public
water supplies?
i. Exposure of people or property to water
related hazards such as flooding or
tidal waves?
PLANT LIFE. Will the proposal result in:
a. Change in the diversity of species, or
number of any species of plants
(including trees, shrubs, grass, crops,
and aquatic plants)?
b. Reduction of the numbers of any unique,
rare or endangered species of plants?
C. Introduction of new species of plants
into an area, or in a barrier to the
normal replenishment of existing
species?
d. Reduction in acreage of any agri-
cultural crop?
ANIMAL LIFE. Will the proposal result in:
a. Change in the diversity of species, or
numbers of any species of animals
(birds, land animals including reptiles,
fish and shellfish, benthic organisms
or insects)?
b. Reduction of the numbers of any unique,
rare or endangered species of animals?
Yes Maybe No
X
X
X
/:1
X
ON
X
X
X
N
7.
3
a
10.
11.
C. Introduction of new species of animals
into an area, or result in a barrier to
the migration or movement of animals?
d. Deterioration to existing fish or
wildlife habitat?
NOISE. Will the proposal result in:
a. Increases in existing noise levels?
b. Exposure of people to severe noise
levels?
LIGHT AND GLARE. Will the proposal produce
new light or glare?
LAND USE. Will the proposal result in a
substantial alteration of the present or
planned land use of an area?
NATURAL RESOURCES. Will the proposal
result in:
a. Increase in the rate of use of any
natural resources?
b. Substantial depletion of any non-
renewable natural resources?
RISK OF UPSET. Will the proposal involve:
a. A risk of an explosion or the release
of hazardous substances (including,
but not limited to, oil, pesticides,
chemicals or radiation) in the event
of an accident or upset conditions?
b. Possible interference with an
emergency response plan or an
emergency evacuation plan?
POPULATION. Will the proposal alter the
location, distribution, density, or growth
rate of the human population of an area?
Yes Maybe No
X
X
X
X
X
/:4
X
X
X
0
Yes Maybe No
12. HOUSING. Will the proposal affect existing
housing or create a demand for additional
housing?
X
13. TRANSPORTATION/CIRCULATION. Will the
proposal result in:
a. Generation of substantial additional
vehicular movement?
X
b. Effects on existing parking facilities,
or demand for new parking?
X
C. Substantial impact upon existing
transportation systems?
X
d. Alterations to present patterns of
circulation or movement of people
and/or goods?
X
e. Alterations to waterborne, rail or
air traffic?
X
f. Increase in traffic hazards to motor
vehicles, bicyclists or pedestrians?
X
14. PUBLIC SERVICES. Will the proposal have an
effect upon, or result in a need for new or
altered governmental services in any of the
following areas:
a. Fire protection?
X
b. Police protection?
X
C. Schools?
X
d. Parks or other recreational facilities?
X
e. Maintenance of public facilities,
including roads?
X
f. Other governmental services?
X
15. ENERGY. Will the proposal result in:
a. Use of substantial amounts of fuel or
energy?
b. Substantial increase in demand upon
existing sources of energy, or require
the development of new sources of
energy?
16. U']['II.TTIES. Will the proposal result in a
need for new systems, or substantial alter-
ations to the following utilities:
a. Power or natural gas?
b. Communications systems?
C. Water?
d. Sewer or septic tanks?
e. Storm water drainage?
f. Solid waste and disposal?
17. HUMAN HEALTH. Will the proposal result in:
a. Creation of any health hazard or
potential health hazard (excluding
mental health)?
b. Exposure of people to potential health
hazards?
18. AESTHETICS. Will the proposal result in the
obstruction of any scenic vista or view open
to the public, or will the proposal result in
the creation of an aesthetically offensive
site open to public view?
19. RECREATION. Will the proposal result in an
impact upon the quality or quantity of
existing recreational opportunities?
Yes Maybe No
/:1
X
X
X
X
X
X
X
X
X
X
Yes Maybe No
20. CULTURAL RESOURCES.
a. Will the proposal result in the alter-
ation of or the destruction of a
prehistoric or historic archaeological
site? X
b. Will the proposal result in adverse
physical or aesthetic effects to a
prehistoric or historic building,
structure or object? X
C. Does the proposal have the potential to
cause a physical change which would
affect unique ethnic cultural values? X
d. Will the proposal restrict religious or
sacred uses within the potential
impact area? X
21. MANDATORY FINDINGS OF SIGNIFICANCE.
a. Does the project have the potential to
degrade the quality of the environment,
substantially reduce the habitat of a
fish or wildlife species, cause a fish
or wildlife population to drop below self
sustaining levels, threaten to eliminate
a plant or animal community, reduce the
number or restrict the range of a rare or
endangered plant or animal or eliminate
important examples of the major periods
of California history or prehistory? X
b. Does the project have the potential to
achieve short-term, to the disadvantage
of long-term, environmental goods? (A
short-term impact on the environment is
one which occurs in a relatively brief,
definitive period of time while long-
term impacts will endure well into the
future.) X
C. Does the project have impacts which are
individually limited, but cumulatively
considerable? (A project may impact on
two or more separate resources where
Yes Maybe No
the impact on each resource is rel-
atively small, but where the effect of
the total of those impacts on the
environment is significant.)
d. Does the project have environmental
effects which will cause substantial
adverse effects on human beings, either
directly or indirectly? X
III. DISCUSSION OF ENVIRONMENTAL EVALUATION
X
The following is a discussion of potential project impacts identified as "Maybe" in the Initial
Study. In addition, explanations are provided for items checked "No", which are anticipated
to result in less than significant or insignificant impacts. This discussion has been provided
pursuant to Section 15063 (Initial Study) of the June, 1986 CEQA Guidelines which require
an explanation of potentially significant effects that have been determined not to be
significant.
1. EARTH. Will the proposal result in:
a. Unstable earth conditions or changes in geologic substructures? No.
The proposed project will require excavation to construct a concrete
rectangular channel. A project of this character does not have the potential
to cause unstable earth conditions or substantial changes in geological
substructures.
Sources: Field Observations, Channel Improvement Plans
Soils Report prepared for project by All-American Soils
Mitigation Measures f Monitorings None Required.
b. Disruptions, displacements, compaction or overcovering of soils? Yes.
The proposed channel improvements would involve expanding the channel's
width from 21 feet to approximately 52 feet. In addition, improvements would
include dropping the channel invert approximately two feet and construction
of a vertical wall rectangular channel. Therefore construction activity will
result in disruption, displacement, compaction and overcovering of soil.
However the excavation will not involve substantial alteration therefore this
impact is not significant.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
C. Change In topography or ground surface relief features? No.
The land adjacent to the project site is a relatively level flood plain to the El
Modena -Irvine Channel. Although the project proposes expanding the
channel's width, this is not anticipated to result in a significant alteration in
existing topography or ground surface relief features.
Sources: Field Observations, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
d. The destruction, covering or modification of any unique geologic or physical
features? No.
The project site and the adjacent land does not contain any unique geologic
or physical feature. The project, as proposed, would not significantly impact
any unique geologic or physical features.
Sources: Field Observations
Mitigation Measures /Monitoring: None Required.
e. Any increase in wind or water erosion of soils, either on or off the site? Maybe.
Soil surfaces will be temporarily exposed during improvement of the channel,
thus increasing the potential for soil erosion. To prevent erosion and
subsequent siltation, the Contractor will be required to comply with standard
engineering practices for erosion control. After project completion, the
proposed concrete line channel would reduce channel and bank erosion.
Sources: Channel Improvement Plans
Mitigation Measures f Monitoring All Standard engineering practices
for erosion shall be required by the Public Works Department during
plan check.
f. Changes in deposition or erosion of beach sands, or changes in siltation,
deposition or erosion which may modify the channel of a river of a stream or the
bed of the ocean or any bay, inlet or lake? Maybe.
The project would modify the El Modena -Irvine channel by improving it from
an existing earthen channel to a concrete channel thereby reducing the
potential erosion of the channel. Therefore this is not identified as a
significant adverse impact. Velocities may increase slightly where the channel
improvements transition into the natural channel.
Sources: Preliminary Design Study El Modena - Irvine Channel
Facility for Michelle Drive to Santa Ana Freeway.
Mitigation Measures /Monitoring_ None Required.
g. Exposure of people or property to geologic hazards such as earthquakes,
landslides, mudslides, ground failure, or similar hazards? No.
Adherence to standard engineering practices design criteria relative to seismic
and geologic hazards will mitigate any potential impacts that could occur due
to the implementation of the project. The project will not involve exposure
of people to geologic hazards.
Sources: Preliminary Design Report
Mitigation Measures /Monitoring: None Required.
2. AIR. Will the proposal result in:
a. Substantial air emissions or deterioration of ambient air quality? No.
- Short-term minor impacts associated with construction may result in local
impacts associated with increased dust/particulate levels. This will be a
temporary construction impact which will exist on a short-term basis during
construction and will be mitigated upon completion of the facility construction.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
b. The creation of objectionable odors? No.
The proposed project will not have the potential to cause any odor impacts,
since no odor -producing activities will be a part of channel improvements.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
C. Alteration of air movement, moisture or temperature, or any change in climate,
either locally or regionally? No.
Improvements to this reach of the El Modena -Irvine Channel will not result
in local or regional changes in climate, due to the limited nature of the
proposed project.
Sources: Channel Improvement Plans
Mitigation Measures/Monitoring: None Required.
3. • WATER. Will the proposal result in:
a. Changes in currents, or the course of direction of water movements in either
marine or fresh waters? No.
The proposed project will not affect currents or direction of water movements.
The project proposes improvements to the existing El Modena -Irvine Channel
but will not change the course or direction of the water movements. Channel
improvements shall ensure that the design flows are conveyed in the channel
section without overtopping.
Sources: Site Observation, Channel Improvement Plan
Mitigation Measures f Monitoring: None Required.
b. Changes in absorption rates, drainage patterns or the rate and amount of surface
runofp Yes.
The project proposes improvements to the El Modena -Irvine Channel, by
increasing the amount of impervious surfaces with rectangular concrete
section. The concrete channel will create an impervious barrier to
groundwater infiltration. However, because of the limited scope of this
project, the impact to groundwater percolation is not significant.
Sources: Preliminary Design Study El Modena - Irvine Channel
Facility F07 Michelle Drive to Santa Ana Freeway.
Mitigation Measures /Monitoring: None Required.
C. Alterations to the course or flow of flood waters? Yes.
The existing capacity of this reach of the El Modena -Irvine Channel is
approximately 3,300 cubic feet per second. The project proposes improving
the channel capacity to convey an 100 -year storm or 7,900 cubic feet per
second. Therefore although the project would result in an alteration to the
flow of flood waters this impact is beneficial in providing an increased level
of flood protection and no mitigation is required.
Sources: Preliminary Design Study El Modena - Irvine Channel
Facility F07, Michelle Drive to Santa Ana Freeway.
Mitigation Measures/Monitoring: None Required.
d. Change in the amount of surface water in any water body? Maybe.
The proposed project will result in an increase in impervious surfaces.
However, the increase will only generate a minimal increase in surface runoff,
therefore no additional mitigation is required.
Sources: Site Observation, Channel Improvement Plan
Mitigation MeasuresZMonitoring_ None Required.
e. Discharge into surface water or in any alteration of surface water quality,
including, but not limited to, temperature, dissolved oxygen or turbidity? No.
The proposed project would involve the improvement of the El Modena -
Irvine Channel, which would include the construction of a concrete channel
lining. Concrete channel lining mitigates the effect of channel erosion and
could therefore improve downstream water quality. The project does not
involve discharge into surface water or alteration of surface water quality;
therefore, no significant impacts are anticipated.
Sources: Preliminary Design Study, Channel Improvement Plans
Mitigation MeasuresZMonitoring_ Construction of concrete lining within
channel. No further mitigation is required.
f. Alteration of the direction or rate of flow of ground waters? Maybe.
The project is not expected to have the potential to affect ground water
direction, however the channel invert is proposed to be lined and would form
a barrier for recharge. However, because of the limited scope of this project,
the impact to ground water percolation is not significant.
Sources: Preliminary Design Study, Channel Improvement Plans
Mitigation MeasuresZMonitoring_ None Required.
g. Change in the quantity of ground waters, either through direct additions or
withdrawals, or through interception of an aquifer by cuts or excavations? No.
A project of this nature does not involve a change in the quantity of ground
waters either through direct additions or withdrawals or through an
interception of an aquifer by cuts or excavations.
Sources: Preliminary Design Study, Channel Improvement Plans
Mitigation MeasuresZMonitoring: None Required.
h. Substantial reduction in the amount of water otherwise available for public water
supplies? No.
The project proposes improvements to the El Modena -Irvine Channel. The
proposed project would not result in reductions in the amount of water
otherwise available for public water supplies.
Sources: Channel Improvement Plans
Mitigation Measures f Monitoring: None Required.
i. Exposure of people or property to water related hazards such as flooding or tidal
waves? No.
The project is proposed to improve the existing flood control channel.
Currently the existing channel has approximately one-third the required 100 -
year conveyance capacity. The project would improve the capacity of the
channel by expanding its width and increasing the depth. Therefore the
project will mitigate the existing flood related hazards and reduce the
potential exposure of people to flooding.
Sources: Preliminary Design Study, Channel Improvement Plans
Mitigation Measures f Monitoring: None Required.
4. PLANT LIFE. Will the proposal result in:
a. Change in the diversity of species or number of any species of plants (including
trees, shrubs, grass, crops and aquatic plants)? Yes.
The project would involve improving the existing earthen channel to a
concrete lined channel, and expanding its width and depth. As the sides of
the channel currently have a slope of 1.5:1 the sides are too steep to support
vegetation. However near the channel bottom there are several areas in
which ruderal species of plants exists. Because of the frequent flooding and
an undependable water supply the more typical riparian community species
are not present. Nevertheless, the project would result in the removal of the
existing plants. However, because of the existing conditions of the channel
it is not anticipated that significant impacts to the diversity or quantity of
plant species will result from improvements to the channel.
Sources: Field Observation, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
b. Reduction of the numbers of any unique, rare or endangered species of plants?
No.
No unique, rare or endangered species of plants are known to exist in the site
vicinity, therefore, no significant impacts are anticipated to occur.
Sources: Site Observation
Mitigation Measures /Monitoring: None Required.
C. Introduction of new species of plants into an area or in a barrier to the normal
replenishment of existing species? Yes.
No new species of plants will be introduced into the project area as a result
of construction of the proposed water facility. The proposed concrete lined
channel could create a barrier to normal replenishment of existing species.
However as few species of plants currently exist on site as a result of the
frequent flooding and undependable water supply, this impact is not
considered significant.
Sources: Site Observation, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
d. Reduction in acreage of any agricultural crop? No.
No reduction in acreage of any agricultural crop will occur, since the project
will not be constructed on areas currently in agricultural production.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
5. ANIMAL LIFE. Will the proposal result in:
a. Change in the diversity of species or numbers of any species of animals (birds,
land animals including reptiles, fish and shellfish, benthic organisms or insects)?
No.
Although the project would modify the existing earthen channel as the channel
does not support a significant wildlife habitat it is not anticipated that the
project would result in change in the diversity of or numbers of any species
of animals. A project of this scope does not have the capacity to cause
significant impacts to animal life.
Sources: Site Observation, Channel Improvement Plans
Mitigation Measures/Monitoring: Implementation of City Ordinance.
b. Reduction of the numbers of any unique, rare or endangered species of animals?
No.
No species of wildlife designated rare, endangered or threatened by the
California Department of Fish and Game or by the U.S. Fish and Wildlife
Service are expected to utilize the project site.
Sources: Project Description, Channel Improvement Plans
Mitigation MeasuresZMonitoring_ None Required.
C. Introduction of new species of animals into an area or result in a barrier to the
migration or movement of animals? No.
No new animal species will be introduced as a result of facility construction.
Although the channel will be expanded the proposed project is not anticipated
to cause animal migration barriers.
Sources: Site Observation, Channel Improvement Plans
Mitigation Measures/Monitoring: None Required.
d. Deterioration to existing fish or wildlife habitat? No.
Although the project would remove existing vegetation, the vegetation is not
considered a substantial fish or wildlife habitat. Therefore, significant impacts
to fish or wildlife habitats will not occur.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
6. NOISE. Will the proposal result in:
a. Increases in existing noise levels? No.
The proposed project is not anticipated to result in any long-term increases
in existing noise levels in the project area. Short-term increases in existing
noise levels are anticipated during construction; however, this is not expected
to be a significant impact.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring None Required.
b. Exposure of people to severe noise levels? No.
Although short-term increases in existing noise levels are anticipated during
construction of facilities, severe noise levels are not expected due to the
nature and location of the proposed project. The land uses immediately
adjacent to project site are agricultural and therefore people will not be
exposed to the noise impacts during construction.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
7. LIGHT AND GLARE. Will the proposal generate new light or glare? No.
The proposed project does not have the potential to generate new light or glare.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring:. None Required.
8. LAND USE. Will the proposal result in a substantial alteration of the present or
planned land use of an area? No.
The improvements to the El Modena -Irvine Channel will not result in an alteration
of land use in the project area due to the nature of the proposed project.
Sources: Channel Improvement Plans
City Zoning Map
Mitigation Measures /Monitoring: None Required.
9. NATURAL RESOURCES. Will the proposal result in:
a. Increase in the rate of use of any natural resources? No.
Minor amounts of resource materials (natural and renewable) will be used in
the improvements of the channel; however, this is not expected to be a
significant impact.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
b. Substantial depletion of any nonrenewable natural resources? No.
Due to the characteristics of the proposed project, substantial depletion of
nonrenewable natural resources is not anticipated.
Sources: Channel Improvement Plans
Mitigation Measures f Monitoring None Required.
10. RISK OF UPSET. Will the proposal involve:
a. A risk of an explosion or the release of hazardous substances (including, but not
limited to, oil, pesticides, chemicals or radiation) in the event of an accident or
upset conditions? No.
The proposed project does not involve hazardous substances. Implementation
of the channel improvements does not include such risks; therefore, significant
impacts in this regard are not anticipated.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
b. Possible interference with an emergency response plan or an emergency
evacuation plan? No.
Construction of the proposed facilities will not interfere with any known
evacuation or emergency response plans.
Sources: Channel Improvement Plans
Mitigation Measures f Monitoring_ None Required.
11. POPULATION. Will the proposal alter the location, distribution, density or growth
rate of the human population of an area? No.
The proposed project is being undertaken to improve the existing El Modena -Irvine
Channel and will not have the capacity to alter the human population.
Sources: Channel Improvement Plans
Mitigation Measures%Monitoring_ None Required.
12. HOUSING. Will the proposal affect existing housing or create a demand for
additional housing? No.
The proposed project is being undertaken to improve the existing flood control
facilities and will not have the capacity to affect housing as there is no adjacent
residential developments.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
13. TRANSPORTATION/CIRCULATION. Will the proposal result in:
a. Generation of substantial additional vehicular movement? No.
The implementation of the proposed project would not result in the
generation of additional vehicular movement and, therefore, does not have
the potential to result in significant vehicular impacts.
Sources: Channel Improvement Plans
Mitigation MeasuresZMonitoring: None Required.
b. Effects on existing parking facilities or demand for new parking? No.
The improvements of the existing flood control facility would not effect
existing parking or create the demand for new parking.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
C. Substantial impact upon existing transportation systems? No.
The project does not have the potential to create a substantial impact upon
the existing transportation systems. Although the Mitchell Drive bridge is
currently a significant hydraulic constraint, the bridge was designed with
consideration for the future channel improvements so there is adequate width
to construct the required channel section. Therefore, the project will not
require modification to the existing bridge or road.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
d. Alterations to present patterns of circulation or movement of people and/or
goods? No.
The project does not require the alteration of any existing roads or bridges.
In addition construction roads are located on both sides of the channel and
are currently used for adjacent improvements. Therefore the construction
activities are not anticipated to alter present patterns of circulation or
movement of people and no mitigation is required.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
e. Alterations to waterborne, rail or air traffic? No.
The proposed project will not affect waterborne, rail or air traffic. A project
of this nature does not have the capacity to alter this type of traffic due to its
distance from such traffic.
Sources: Channel Improvement Plans
Mitigation Measures f Monitorings None Required.
f. Increase in traffic hazards to motor vehicles, bicyclists or pedestrians? No.
The proposed improvements of the El Modena -Irvine Channel will not effect
any roadways and therefore would not increase traffic hazards to motor
vehicles, bicyclists or pedestrians.
Sources: Channel Improvement Plans
Mitigation Measures/Monitorings None Required.
14. PUBLIC SERVICES. Will the proposal have an effect upon or result in a need for
new or altered governmental services in any of the following areas:
a. Fire protection? No.
No significant impacts are anticipated, as the project will not have a significant
demand on fire services.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring:, None Required.
b. Police protection? No.
The improvement of flood control facilities would not affect police protection
services.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitorings None Required.
C. Schools? No.
The proposed project will not generate students and, therefore, would not
create impacts to school services.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
d. Parks or other recreational facilities? No.
The proposed project will not have the potential to significantly affect parks
or recreational facilities due to its location, nature and scope.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
e. Maintenance of public facilities, including roads? No.
Maintenance of the proposed facility would be provided by the Orange County
Environmental Management Agency as part of its standard operations. This
is not considered a significant impact.
Sources: Channel Improvement Plans
Mitigation MeasuresZMonitoring_ None Required.
f. Other governmental services? No.
Additional governmental services are not anticipated to be required as a result
of the proposed project, therefore, the project is not anticipated to result in
significant impacts in this regard.
Sources: Channel Improvement Plans
Mitigation Measures f Monitoring_ None Required.
15. ENERGY. Will the proposal result in:
a. Use of substantial amounts of fuel or energy? No.
The proposed project will utilize minor amounts of fuel and energy for the
construction and maintenance of the proposed project. The impacts are not
considered significant or substantial due to the nature of the project.
Sources: Project Description, Channel Improvement Plans
Mitigation MeasuresZMonitoring,: None Required.
b. Substantial increase in demand upon existing sources of energy or require the
development of new sources of energy? No.
Due to the nature of the proposed project, energy sources and usage required
for project implementation and operation are not considered to be significant.
No additional energy sources will be required for project implementation.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
16. U IUXF . Will the proposal result in a need for new systems or substantial
alterations to the following utilities:
a. Power or natural gas? No.
A project of this type would not require any power or natural gas service.
There no new systems or substantial alteration to existing systems would be
required.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
b. Communication systems? No.
No additional communications system will be required as a result of the
proposed project.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
C. Water? No.
No new water systems or facilities would be required by the project.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring None Required.
d. Sewer or septic tanks? No.
The proposed project will not create a need • for new sewer or septic tank
facilities.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring: None Required.
e. Storm water drainage? Yes.
The project proposes improvements to the existing flood control facility.
Currently the reach of the El Modena -Irvine Channel to be improved has one-
third the required 100 -year conveyance capacity. The proposed project will
mitigate this ' condition. Therefore no additional mitigation is required.
Sources: Preliminary Design Study El Modena - Irvine Channel
Facility F07 Michelle Drive to Santa Ana Freeway.
Mitigation Measures /Monitoring: None Required.
f. Solid waste and disposal? No.
The proposed project does not involve solid waste or disposal.
Sources: Channel Improvement Plans
Mitigation Measures/Monitoring: None Required.
17. HUMAN HEALTH. Will the proposal result in:
a. Creation of any health hazard or potential health hazard (excluding mental
health) ? No.
The proposed project will not have the potential to create any health or
potential health hazards. Facility improvements would be based on standard
engineering practices.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring: None Required.
b. Exposure of people to potential health hazards? No.
No substances or practices constituting the potential to expose people to
health hazards will occur as a part of the proposed project.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
18. AESTHETICS. Will the proposal result in the obstruction of any scenic vista or
view open to the public, or will the proposal result in the creation of an aesthetically
offensive site open to public view? Maybe.
Short-term aesthetic impacts could occur due to the viewing of construction related
activities. These impacts are temporary in nature and are not considered significant.
The placement of rip -rap in contrast to the existing earthen channel may be viewed
by some negatively. However this impact is not considered significant.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring_ None Required.
19. RECREATION. Will the proposal result in an impact upon the quality or quantity
of existing recreational opportunities? No.
The proposed flood facility improvements do not have the potential to effect existing
recreational opportunities due to the distance from such facilities and the nature of
project.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
20. CULTURAL RESOURCES
a Will the proposal result in the alteration of or the destruction of a prehistoric or
historic archaeological site? No.
Improvement to the flood control facility is not anticipated to result in
significant impacts to known or unknown prehistoric or historical
archaeological resources as the improvements will be to an existing drainage
facility.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
b. Will the proposal result in adverse physical or aesthetic effects to a prehistoric or
historic building, structure or object? No.
As no prehistoric or historic structures have been identified in the project
area, no significant impacts are anticipated.
Sources: Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
C. Does the proposal have the potential to cause a physical change which would
affect unique ethnic cultural values? No.
There are no known features of the project that have the characteristics to
cause a physical change which would affect unique ethnic cultural values.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring_ None Required.
d. Will the proposal restrict existing religious or sacred uses within the potential
impact area? No.
No religious or sacred uses have been identified within the project area;
therefore, no impacts are anticipated as a result of the proposed project.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring None Required.
21. MANDATORY FINDINGS OF SIGNIFICANCE
a. Does the project have the potential to degrade the quality of the environment,
substantially reduce the habitat of a fish or wildlife species, cause a fish or
wildlife population to drop below self sustaining levels, threaten to eliminate a
plant or animal community, reduce the number or restrict the range of a rare or
endangered plant or animal or eliminate important examples of the major periods
of California history or prehistory? No.
The proposed project involves improving an approximately 830 foot section
of the existing El Modena -Irvine Channel; this improvement would not have
the potential to have permanent significant effects upon the environment.
Sources: Preliminary Design Study El Modena - Irvine Channel
Facility F07 Michelle Drive to Santa Ana Freeway.
Mitigation Measures/ Monitoring_ None Required.
b. Does the project have the potential to achieve short-term, to the disadvantage of
long-term, environmental goals? (A short-term impact on the environment is one
which occurs in a relatively brief, definitive period of time while long-term impacts
will endure well into the future.) No.
The proposed project considered in this Initial Study consists of channel
improvements to section of the El Modena -Irvine Channel to improve the
capacity of the drainage channel. Currently the channel has one-third the
required 100 -year conveyance capacity, therefore this project would mitigate
present flooding hazards as part of the City's and the Orange County
Environmental Management Agency's long-term goals and responsibilities.
Therefore, the proposed project does not have the potential to achieve short-
term goals to the disadvantage of long-term goals.
Sources: Preliminary Design Study El Modena - Irvine Channel
Facility F07 Michelle Drive to Santa Ana Freeway.
Mitigation Measures /Monitoring: None Required.
C. Does the project have impacts which are individually limited, but cumulatively
considerable? (A project may impact on two or more separate resources where
the impact on each resource is relatively small, but where the effect of the total
of those impacts on the environment is significant.) No.
Due to its nature, the proposed project will not involve significant cumulative
impacts, as it is merely improvement to an existing public facility.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures f Monitoring: None Required.
d. Does the project have environmental effects which will cause substantial adverse
effects on human beings, either directly or indirectly? No.
Due to its limited nature, the proposed project will not produce environmental
impacts which will cause significant adverse effects on human beings.
Implementation of the proposed project is expected to have some minor,
temporary impacts; however, the proposed project does not have the potential
to produce substantial adverse effects upon humans.
Sources: Project Description, Channel Improvement Plans
Mitigation Measures /Monitoring: None Required.
IV.DETERMENATION
(To be completed by the Lead Agency).
On the basis of this initial evaluation:
I find that the proposed project COULD NOT have
a significant effect on the environment, and a
NEGATIVE DECLARATION will be prepared.
I find that although the proposed project could have
a significant effect on the environment, there will
not be a significant effect in this case because the
mitigation measures described on the attached sheet
have been added to the project. A NEGATIVE
DECLARATION WILL BE PREPARED.
I find the proposed project MAY have a significant
effect on the environment, and an ENVIRONMENTAL
IMPACT REPORT is required.
Date: 1`%4 Y ,Z // , If y'D Signature
For : Ger Qf' Tu.STin/
X
NOTE: This checklist has been derived directly from the California Environmental
Quality Act Guidelines, Appendix I.