R-2015-232 2015-12-14RESOLUTION NO. R2015-232
A Resolution of the City Council of the City of Pearland, Texas, authorizing the
City Manager or his designee to enter into a contract with Halff Associated, in
the amount of $106,575.00 for engineering services associated with the joint
City of Pearland/Brazoria Drainage District No. 4 Master Drainage Plan Project
Phase I.
BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF PEARLAND, TEXAS:
Section 1. That certain contract for engineering services associated with the joint City of
Pearland/Brazoria Drainage District No. 4 Master Drainage Plan Project Phase I, a copy of which is
attached hereto as Exhibit "A" and made a part hereof for all purposes, is hereby authorized and
approved.
Section 2. That the City Manager or his designee is hereby authorized to execute and
the City Secretary to attest a contract for engineering services associated with the joint City of
Pearland/Brazoria Drainage District No. 4 Master Drainage Plan Project Phase I.
PASSED, APPROVED and ADOPTED this the 14th day of December, A.D., 2015.
ATTEST:
TOM REID
MAYOR
%/Q 2
APPROVED AS TO FORM:
DARRIN M. COKER
CITY ATTORNEY
Exhibit A
Resolution No. R2015-232
MEMORANDUM OF UNDERSTANDING
This Memorandum of Understanding (`MOU"), made and entered into by and
between the City of Pearland, a home rule municipality incorporated under the laws of
the State of Texas, hereinafter ("City"), and Brazoria Drainage District No.4, a body
corporate and politic under the laws of the State of Texas, hereinafter ("District");
RECITALS
Whereas, the City and District understand the importance of developing a
comprehensive Master Drainage Plan to develop and guide future drainage policies and
improvements in their respective jurisdictions; and
Whereas, the City and District desire to utilize the same consultant to develop a
Master Drainage Plan that will be used by both entities in implementing drainage
policies; and
Whereas, the City and District desire to set forth desire an MOU to set forth their
respective responsibilities with regard to the Master Drainage Plan; and
WITNESSETH
NOW THEREFORE, in consideration of the mutual covenants, agreements and
benefits to the parties herein named, it is hereby agreed as follows:
I. Responsibilities of the Parties
A. The City and District agree to select an engineer that will prepare a scope
of services to develop Master Drainage Plan to serve as a drainage policy
implementation tool for both entities.
B. Upon selection of an engineer, City and District shall separately contract
with the engineer to develop the Master Drainage Plan, and each party
shall be responsible for 50% of the total costs associated with preparation
of the Master Drainage Plan.
C. City and District agree to present the final version Master Drainage Plan to
their respective governing bodies for approval and adoption.
II. CURRENT FUNDS AVAILABLE
Both parties hereto represent that they have appropriated sufficient funds to
satisfy their respective obligations under this Agreement.
III. MISCELLANEOUS
A. City and District recognize and agree that City, in performance of this
MOU, shall act as an independent contractor and shall have control of its
own work and the manner in which it is performed.
B. City and District recognize and agree that the District, in performance of
this MOU, shall act as an independent contractor and shall have control of
its own work and the mariner in which it is performed.
C. City and District shall comply with all applicable laws, regulations and
requirements in performance of their respective obligations under this
MOU.
D. City and District recognize and agree that nothing herein shall be
construed to create any rights in third parties.
E. City and District agree that no party shall have the right to seek
indemnification or contribution from any other party hereto for any losses,
costs, expenses, or damages directly or indirectly arising, in whole or part
form this MOU.
Each person signing below represents that he or she has read this MOU in its entirety,
including any and all attachments and exhibits, understands its terms, is duly authorized
to execute this MOU on behalf of the party indicated by his or her name below and
agrees on behalf of said party that the party will be bound by these terms.
SIGNED and ENTEREDis 5 th
day of January , 2016.
BRAZORIA DRAINAGE DISTRICT No.4
Mike Yost, Superintendent
ATTES
//
Kimbe ey WooJ:4 1, Director of
Admin Servi•es
CITY OF PEARLAND
earson, Cit S' Manager
Exhibit B
CONTRACT FOR PROFESSIONAL SERVICES
THIS CONTRACT is entered into upon final execution by and between the City of Pearland
("CITY") and Halff Associates, Inc. ("CONSULTANT").
The CITY engages the CONSULTANT to perform professional services for a project known and
described as City of Pearland & Brazoria Drainage District No. 4 Master Drainage Plan
("PROJECT").
SERVICES OF THE CONSULTANT
The CONSULTANT shall perform the following professional services to CITY standards and in
accordance with the degree of care and skill that a professional in Texas would exercise under
the same or similar circumstances:
A. The CONSULTANT shall prepare a drainage master plan. See Exhibit A,
attached, for a detailed SCOPE OF WORK and PROJECT schedule. The
PROJECT schedule shall be submitted in digital and hard copy form in the
Microsoft Project for Windows format.
B. The CONSULTANT shall prepare and submit a detailed opinion of estimated cost
of the PROJECT.
C. The CONSULTANT acknowledges that the CITY (through its employee
handbook) considers the following to be misconduct that is grounds for
termination of a CITY employee: Any fraud, forgery, misappropriation of funds,
receiving payment for services not performed or for hours not worked,
mishandling or untruthful reporting of money transactions, destruction of assets,
embezzlement, accepting materials of value from vendors, or consultants, and/or
collecting reimbursement of expenses made for the benefit of the CITY. The
CONSULTANT agrees that it will not, directly or indirectly; encourage a CITY
employee to engage in such misconduct.
D. The CONSULTANT shall submit all final construction documents in both hard
copy and electronic format. Plans shall be AutoCAD compatible and all other
documents shall be Microsoft Office compatible. The software version used shall
be compatible to current CITY standards. Other support documents, for example,
structural calculations, drainage reports and geotechnical reports, shall be
submitted in hard copy only. All Record Drawings electronic files shall be
submitted to the CITY in TIF format.
E. The CONSULTANT recognizes that all drawings, special provisions, field survey
notes, reports, estimates and any and all other documents or work product
generated by the CONSULTANT under the CONTRACT shall be delivered to the
CITY upon request, shall become subject to the Open Records Laws of this State.
Design 1 of6 D1. Revised 1/14
F. The CONSULTANT shall procure and maintain for the duration of this
Agreement, insurance against claims for injuries to persons, damages to property,
or any errors and omissions relating to the performance of any work by the
CONSULTANT, its agents, employees or subcontractors under this Agreement,
as follows:
(1)
Workers' Compensation as required by law.
(2) Professional Liability Insurance in an amount not less than $1,000,000 in
the aggregate.
(3)
Comprehensive General Liability and Property Damage Insurance with
minimum limits of $1,000,000 for injury or death of any one person,
$1,000,000 for each occurrence, and $1,000,000 for each occurrence of
damage to or destruction of property.
(4) Comprehensive Automobile and Truck Liability Insurance covering
owned, hired, and non -owned vehicles, with minimum limits of
$1,000,000 for injury or death of any one person, $1,000,000 for each
occurrence, and $1,000,000 for property damage.
The CONSULTANT shall include the CITY as an additional insured under the
policies, with the exception of the Professional Liability Insurance and Workers'
Compensation. Certificates of Insurance and endorsements shall be furnished to
the CITY before work commences. Each insurance policy shall be endorsed to
state that coverage shall not be suspended, voided, canceled, and/or reduced in
coverage or in limits ("Change in Coverage") except with prior written consent of
the CITY and only after the CITY has been provided with written notice of such
Change in Coverage, such notice to be sent to the CITY either by hand delivery to
the City Manager or by certified mail, return receipt requested, and received by
the City no fewer than thirty (30) days prior to the effective date of such Change
in Coverage. Prior to commencing services under this CONTRACT,
CONSULTANT shall furnish CITY with Certificates of Insurance, or formal
endorsements as required by this CONTRACT, issued by CONSULTANT'S
insurer(s), as evidence that policies providing the required coverage, conditions,
and limits required by this CONTRACT are in full force and effect.
Design 2 of 6 1)1. Revised 1/14
G. The CONSULTANT shall indemnify and hold the CITY, its officers, agents, and
employees, harmless from any claim, loss, damage, suit, and liability of every
kind for which CONSULTANT is legally liable, including all expenses of
litigation, court costs, and attorney's fees, for injury to or death of any person, for
damage to any property, or errors in design, any of which are caused by the
negligent act or omission of the CONSULTANT, his officers, employees, agents,
or subcontractors under this CONTRACT.
H. All parties intend that the CONSULTANT, in performing services pursuant to this
CONTRACT, shall act as an independent contractor and shall have control of its
own work and the manner in which it is performed. The CONSULTANT is not to
be considered an agent or employee of the CITY.
SECTION II - PERIOD OF SERVICE
This CONTRACT will be binding upon execution and end September 1, 2016 .
SECTION 111 - CONSULTANT'S COMPENSATION
A. The total compensation for the services performed shall not exceed the total noted
in Section B.
B. The CITY shall pay the CONSULTANT in installments based upon monthly
progress reports and detailed invoices submitted by the CONSULTANT based
upon the following:
1. Basic Services (Lump Sum) $106,575.00
2. Additional Services shall require independent and specific authorization
and shall be billed as (Lump Sum):
3. Bid Phase Services (Hourly Not to Exceed)
4. Construction Phase Services (Hourly Not to Exceed)
5. Reimbursable Expenses (Not to Exceed)
6. Total: $106,575.00
C. The CITY shall make payments to the CONSULTANT within thirty (30) days
after receipt and approval of a detailed invoice. Invoices shall be submitted on a
monthly basis.
Design 3 of6 DI. Revised 1/14
SECTION IV - THE CITY'S RESPONSIBILITIES
A. The CITY shall designate a project manager during the term of this CONTRACT.
The project manager has the authority to administer this CONTRACT and shall
monitor compliance with all terms and conditions stated herein. All requests for
information from or a decision by the CITY on any aspect of the work shall be
directed to the project manager.
B. The CITY shall review submittals by the CONSULTANT and provide prompt
response to questions and rendering of decisions pertaining thereto, to minimize
delay in the progress of the CONSULTANT'S work. The CITY will keep the
CONSULTANT advised concerning the progress of the CITY'S review of the
work. The CONSULTANT agrees that the CITY'S inspection, review,
acceptance or approval of CONSULTANT'S work shall not relieve
CONSULTANT'S responsibility for errors or omissions of the CONSULTANT or
its sub-consultant(s) or in any way affect the CONSULTANT'S status as an
independent contractor of the CITY.
SECTION V - TERMINATION
A. The CITY, at its sole discretion, may terminate this CONTRACT for any reason -
- with or without cause -- by delivering written notice to CONSULTANT
personally or by certified mail at 14800 St. Mary's Lane, Suite 160, Houston,
Texas 77079. Immediately after receiving such written notice, the
CONSULTANT shall discontinue providing the services under this CONTRACT.
B. If this CONTRACT is terminated, CONSULTANT shall deliver to the CITY all
drawings, special provisions, field survey notes, reports, estimates and any and all
other documents or work product generated by the CONSULTANT under the
CONTRACT, entirely or partially completed, together with all unused materials
supplied by the CITY on or before the 15`h day following termination of the
CONTRACT.
C. In the event of such termination, the CONSULTANT shall be paid for services
performed prior to receipt of the written notice of termination. The CITY shall
make final payment within sixty (60) days after the CONSULTANT has delivered
to the CITY a detailed invoice for services rendered and the documents or work
product generated by the CONSULTANT under the CONTRACT.
D. If the remuneration scheduled under this contract is based upon a fixed fee or
definitely ascertainable sum, the portion of such sum payable shall be
proportionate to the percentage of services completed by the CONSULTANT
based upon the scope of work.
Design 4 of 6 DI. Revised 1/14
E. In the event this CONTRACT is terminated, the CITY shall have the option of
completing the work, or entering into a CONTRACT with another party for the
completion of the work.
F. If the CITY terminates this CONTRACT for cause and/or if the CONSULTANT
breaches any provision of this CONTRACT, then the CITY shall have all rights
and remedies in law and/or equity against CONSULTANT. Venue for any action
or dispute arising out of or relating to this CONTRACT shall be in Brazoria
County, Texas. The laws of the State of Texas shall govern the terms of this
CONTRACT. The prevailing party in the action shall be entitled to recover its
actual damages with interest, attorney's fees, costs and expenses incurred in
connection with the dispute and/or action. CONSULTANT and CITY desire an
expeditious means to resolve any disputes that may arise between under this
CONTRACT. To accomplish this, the parties agree to mediation as follows: If a
dispute arises out of or relates to this CONTRACT, or the breach thereof, and if
the dispute cannot be settled through negotiation, then the parties agree first to try
in good faith, and before pursuing any legal remedies, to settle the dispute by
mediation of a third party who will be selected by agreement of the parties.
SECTION VI — ENTIRE AGREEMENT
This CONTRACT represents the entire agreement between the CITY and the CONSULTANT
and supersedes all prior negotiations, representations, or contracts, either written or oral. This
CONTRACT may be amended only by written instrument signed by both parties.
SECTION VII — COVENANT AGAINST CONTINGENT FEES
The CONSULTANT affirms that he has not employed or retained any company or person, other
than a bona fide employee working for the CONSULTANT to solicit or secure this
CONTRACT, and that he has not paid or agreed to pay any company or person, other than a
bona fide employee, any fee, commission, percentage brokerage fee, gift, or any other
consideration, contingent upon or resulting from the award or making of the CONTRACT. For
breach or violation of this clause, the CITY may terminate this CONTRACT without liability,
and in its discretion, may deduct from the CONTRACT price or consideration, or otherwise
recover, the full amount of such fee, commission, percentage brokerage fee, gift, or contingent
fee that has been paid.
Design 5 oI'6 1)1. Revised 1/14
SECTION VIII- SUCCESSORS AND ASSIGNS
This CONTRACT shall not be assignable except upon the written consent of the parties hereto.
Y OF P ALAND, TEXAS DATE
- NSULTA T TeR.Ar M, 6A/2/1-
2.4/ 40V 20/5
DATE
Design 6 of 6 D1. Revised 1114
CITY OF PEARLAND & BRAZORIA DRAINAGE DISTRICT NO.4
MASTER DRAINAGE PLAN
SCOPE OF WORK
November 11, 2015
Preface
Over the last several decades, the City of Pearland (City) and Brazoria Drainage District No. 4 (BDD4) have
experienced significant growth and development throughout. The last decade alone has seen a two -fold
increase in the area's population. With development comes an increased risk of flooding from streams as
well as other sources, which can present hazards to the public and impede growth. In an effort to more
effectively plan drainage improvements and consider regulatory measures aimed at minimizing negative
development impacts, the City and BDD4 have taken a proactive approach. As such, the City of Pearland
and Brazoria Drainage District No. 4 have selected Halff Associates to prepare a drainage master plan
update for the combined area. The services and products resulting from the study shall be referred to as
the City of Pearland/Brazoria Drainage District No. 4 Master Drainage Plan.
The Pearland/Brazoria DD4 Drainage Master Plan is located within the shared boundary of the City and
BDD4, which encompasses a combined area of nearly 97 sq. mi. The project is generally bound by Clear
Creek to the north and FM 521 to the west. The eastern and southern boundaries are Tess clearly
demarcated, with a portion of the City extending into Harris County on the east side of Clear Creek. The
Galveston County line serves as the remainder of the eastern boundary. A majority of BDD4 is located
north of SH6, with the exception of the area near the Fort Bend County line, which includes portions of
Iowa Colony and Manvel.
Streams to be included in the study will be Clear Creek, Hickory Slough, Mary's Creek, Cowart Creek and
associates ditches and diversions, Chigger Creek and Mustang Bayou. The specific tasks to be completed
for each stream will be specified in subsequent sections of this scope. The study area lies within fourteen
(14) FEMA FIRM panels in three counties; Brazoria, Harris, and Fort Bend. The panels include those in
Brazoria (48039C 00101, 0020H, 00301, 00351, 00401, 00451, 0110H), in Harris (48201C 1010L, 1030L,
1035L, 1055L), and in Fort Bend (48157 0305L, 0315L, 0455L). The effective dates vary.
Project Purpose
The purpose of the Master Drainage Plan is to conduct a two-phase update of the existing drainage
information. While there does not appear to be an actively used drainage master plan, both the City and
BDD4 have an extensive collection of drainage reports, studies, models, infrastructure plans, and other
data that can be leveraged to plan for and encourage growth in a safe and cost-effective manner. In
general, the tasks to be performed in each of the two phases are as follows:
• Phase 1 — Collection of all relevant drainage information, including plans, reports, drainage
complaints, flood insurance claims, hydrologic and hydraulic models, drainage criteria
information, funding sources, etc.; Evaluation of the plans, reports, models, criteria, etc.; field
investigation, verification, and documentation of existing drainage infrastructure; Generation of
a digital inventory for all data collected; Updated drainage area and zone of influence
delineations; Development and presentation of recommendations for Phase 2, including data and
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modeling needs, alternative funding sources (such as Flood Protection Planning Grants), criteria
updates, and implementation strategies.
• Phase II — (NOT INCLUDED IN THIS CONTRACT) Updates to the existing conditions base modeling
for both hydrology and hydraulics, which may include a variety of tools ranging from traditional
10 steady models to more advanced 2D modeling strategies; Identification of existing and future
flood hazards and their sources; Comparisons of the existing flood mapping to the flood loss data;
Evaluation of future growth patterns; Development of potential flood improvement alternatives
using various mitigation strategies; Cost estimation and prioritization of potential capital projects;
Implementation of the Master Drainage Plan and updates to the Drainage Criteria.
A preliminary scope for Phase II will be prepared as part of the Phase I recommendations and/or Flood
Protection Planning Grant application. Upon completion of Phase I and delivery of the recommendations
to the City and BDD4, a detailed final scope will be prepared. The specific tasks associated with Phase I
are discussed in the following scope of services.
Project Scope
Task 1: Wagon Trail Road Drainage Evaluation
In response to historical as well as recent flooding in the area along Wagon Trail Road, Halff will evaluate
the drainage patterns in an effort to identify flooding sources and recommend potential flood reduction
measures in the area. The study area is located within the City of Pearland along Wagon Trail Road,
between W Broadway St (FM 518) to the north and Mary's Creek to the south. There are several low-
lying structures in the vicinity that experience flooding on a regular basis. This task will start upon approval
of the contract and will be completed independently of the Master Drainage Plan discussed in subsequent
tasks. Specific tasks relating to the Wagon Trail Rd. drainage evaluation include:
a. Review of Existing Drainage Information
i. Review the memorandum, calculations, and recommendations provided by IEA to the City
in the 2013 report, Wagon Trail Road Drainage Improvement from Bardet Road to the
Outfall at Fite Road Bridge.
ii. Review plans and drainage calculations relating to the construction of the Corrigan Bypass
channel.
b. Topographic Survey
i. Halff will prepare a 3-D Microstation file of 100' cross-sections limited to grade breaks
and paving elevations within the outside top -of -bank of the roadside swale ditches and
driveway approaches located along Wagon Trail Road (from Broadway to Ochoa), Cantu
and Ochoa. Flowline information will be collected where physically possible on visible
storm water facilities. Finish floor elevations of up to 6 adjacent structures will be
tied. Benchmark elevations will be on the same datum as the City of Pearland. This
proposal does not include uncovering or field tying any other improvements, above
ground utilities or subsurface utilities, trees.
ii. Right of Entry permissions will need to be obtained by the City.
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c. Existing Conditions 2D Modeling
i. Develop of a 2D computational mesh for the area generally bound by W Broadway Rd
(north), Mary's Creek (south), Corrigan Bypass (east) and O'day Ditch (west). The initial
2D surface will include minimal feature detail. The detail will be refined after the initial
run to focus on those areas where flooding is present.
ii. Develop rainfall hyetographs for the 3 -year (design) storm, 100 -year, and recent historical
rainfall obtained from gage records available on the Harris County Flood Warning System
website. Infiltration losses will be estimated using HEC -HMS and the excess rainfall
hyetograph will be entered into the 2D model for analysis.
iii. Evaluate the modeled drainage patterns and compare to known flooding instances.
Adjust and/or refine model detail based on initial findings.
iv. Halff will meet with the City/BDD4 to discuss the existing conditions analysis findings and
consider potential improvements to be modeled.
d. Flood Reduction Alternatives Analysis
i. Consider potential improvements to reduce flooding in the project area. Halff will
evaluate up to three (3) small projects in the area, which may include but are not limited
to increasing roadside ditch capacity, storm sewer improvements, and rerouting flow
away from Wagon Trail Rd to the Corrigan Bypass.
ii. Flood reduction alternatives will be sized using methods specified in the City/BDD4 design
criteria.
iii. Halff will develop conceptual level opinions of probable construction cost (OPCC) for each
alternative. The OPCC's will include a contingency of 30-35% to account for potential
conflicts during the design and construction phase.
iv. Halff will prepare a technical memorandum discussing the analysis methodology, findings,
improvement recommendations and associated costs.
Task 2: Project Management and Coordination
Halff Associates project management activities shall include task leadership and direction, telephone and
written communication, project status reports, project progress meetings, project invoicing, and
personnel and data management among other general project management activities. Specific meetings
beyond staff management coordination and regular communication include the following:
e. Project Meetings
i. Attend one (1) project kickoff meeting with staff from both the City and BDD4. The
meeting will be coordinated by the Halff Project Manager and is intended to discuss key
items such as project schedule, budget, and any specific directives. Halff will provide a
preliminary schedule of tasks.
ii. Attend up to three (3) progress meetings throughout Phase I to discuss specific tasks such
as data collection and inventory, model evaluation, and field verification, project tracking
tools, etc.
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iii. Attend one (1) meeting specifically related to the current drainage criteria and any
desired updates or clarifications.
iv. Attend two (2) meetings specifically related to the Phase I recommendations. The first
shall be a preliminary recommendations discussion and the second shall be a final
recommendations meeting, which shall be conducted near the Final Phase I submittal
deadline.
v. Attend one (1) public meeting or City Council meeting for the City of Pearland to discuss
process, findings, and recommendations for Phase II and answer questions.
vi. Attend one (1) public meeting or Brazoria County Commissioners Court meeting to discuss
process, findings, and recommendations for Phase II and answer questions.
vii. Meetings listed do NOT include those necessary to apply for or fulfill the obligations of an
awarded Flood Protection Planning Grant. Application meetings are specifically identified
in Task 7 and public meeting required to meet grant obligations will be conducted if a
grant is awarded and will be included with the Phase 11 scope of services.
viii. Meeting notes shall be submitted to the City and BDD4 Project Managers within five (5)
working days after each meeting.
f. Development of a Project Management Plan
i. Develop a Project Management Plan (PMP) for the City and BDD4. This is a planning and
communication document that will include specific information regarding to the scope
and budget, as well as schedule, team resources, discussion of quality control procedures,
and a communication plan. PMP shall be completed prior to the project kickoff meeting.
ii. Within the PMP, the project schedule will be provided. Any delays to the project schedule
shall be discussed in writing and provided to the City and BDD4 for review and approval.
g.
Project Status Reports
i. Monthly project status reports shall be provided to the City and BDD4 with the monthly
invoices. Separate monthly invoices will be provided for each agency, but the same
project status reports will be provided. Progress shall include notes regarding work
completed in the preceding billing cycle, work expected to be completed in the next cycle,
and any outstanding questions or issues for discussion.
h. Web Map Development
i. A significant part of the communication and coordination effort for the Master Drainage
Plan will be transparency of Halff's progress. Beyond the normal communication
channels, Halff will develop a project web map, which may be accessed by both the City
and BDD4. The web map will be continually updated with the data inventory and field
data collection efforts that will be detailed in subsequent sections. Access permissions
for the web map will be set to meet the specifications of the City and BDD4.
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Task 3: Data Collection and Model Inventory
Data Collection and model inventory tasks will generally include gathering and organization of all data
provided, both hard copy and digital format. Data and models shall be provided by the City and BDD4, as
well as from other sources such as Fort Bend County Drainage District (FBDD), Harris County Flood Control
District (HCFCD), the Federal Emergency Management Agency (FEMA), the U.S Army Corps of Engineers
(USACE), and other consultants if necessary. The data shall be organized and linked to a GIS dataset so
that future data collection efforts by the City, BDD4, and other interested parties will be more efficient.
Specific tasks relating to data collection include the following:
a. GIS Data Collection
i. Data requests will be directed to the City and BDD4, with additional requests made to
outside entities if necessary.
ii. Halff will collect and catalogue all relevant GIS data including, but not limited to, terrain
(LiDAR) Data, landuse/zoning, FEMA (both mapping and loss data), planimetrics, political
boundaries, development and subdivisions, detention locations, utility information, etc.
iii. All GIS data gathered will be organized in Geodatabase format for use during the Master
Drainage Plan process and will be provided back to the City and BDD4 as part of the Phase
I Submittal.
b. H&H Model Collection
i. Models for Clear Creek will be downloaded from HCFCD website. In addition, USACE has
a Federal project planned for Clear Creek. The model will be requested to ensure that
planning efforts within the MDP area do not negatively impact the project.
ii. Hydraulic models for the Clear Creek Tributaries, including Mary's Creek, Hickory Slough,
Cowart Creek, and Chigger Creek will be requested from the City and BDD4. Hydrologic
models for the tributaries will also be requested; however, they are also included in the
Clear Creek model prepared for HCFCD.
iii. Hydrologic and hydraulic models for Mustang Bayou will be requested from the City
and/or BDD4 and, if necessary, FBDD. Mustang Bayou is not a tributary of Clear Creek
and, as such, will not be connected to HCFCD.
iv. Additional models developed within the project boundary will also be requested. These
include modeling developed for regional detention pond projects, channel improvement
projects, large scale developments, etc. A preliminary look at the models will be done to
determine if they are relevant or if the watershed models include that information.
c. Drainage Report and Record Drawings Collection
i. Drainage reports developed for major development projects or capital projects, including
detention, channel improvement, and storm sewer improvement, will be requested from
the City and BDD4
ii. Record or "As -Built" drawings will be requested for improvements including, but not
limited to, creek/bayou improvements, detention ponds, storm sewer trunk line, and
major developments. Major detention facilities, such as the Mary's Creek Regional
Detention Basin and the Southwest Environmental Center Regional Detention Basin, will
be collected as part of this effort.
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d. Data Organization and GIS Inventory
i. As part of the data collection and inventory process, Halff will generate a digital record of
all data including models, reports, and record drawings. Digital scans will be taken of each
document and will be stored in an Adobe Acrobat (.pdf) format. The data will be managed
by Halff Associates and delivered to the City and BDD4.
ii. A GIS polygon layer will be created to represent the location of each report, plan set, and
model identified during the project. Within the polygon feature class, records will contain
the name of the project or study, agency responsible, a short description, and the pdf file
of the report as a geodatabase attachment. Specific exhibits, such as those identifying
feature ownership, will be provided with the submittal discussed in Task 7: Phase I
Submittal. Areas within the feature classes will include but are not limited to:
a. Areas depicting physical changes such as detention ponds, channel
improvements, storm sewer trunk line improvements, or others completed
as part of CIP or private development projects. Associated data fields will
include information such as feature owner, type of improvement, date of
completion, engineer of record, impacted area, and other fields requested by
the City and BDD4.
b. Hydrologic studies performed for watersheds or smaller areas will be
identified with a watershed boundary. Associated data fields may include
watershed name, agency responsible, receiving stream, watershed area,
study date, engineer of record, and other fields requested by the City and
BDD4.
c. Hydraulic studies performed for creeks, bayous, or ditches may be identified
with a linear feature denoting the specific location and limits of the study.
Associated data fields may include stream name, owner, receiving stream (if
applicable), study length, study date, engineer of record, and other fields
requested by the City and BDD4.
iii. The Geodatabase will be structured such that as new studies and projects are completed,
they may be added into the GIS for future identification.
iv. Halff will work with the City and BDD4 to transfer the data such that the proper linkage is
maintained and the GIS and .pdf and model files remain connected. In the case of models,
a file location may be provided or a .zip file with the relevant model files may be linked.
v. The data inventory progress may be continually tracked and accessed by the City and
BDD4 using the project web map discussed in the Transparency Tools section above.
vi. Additional levels of data inventory may be provided to the City and BDD4 upon request,
but are NOT included in this scope of services. This includes scans of individual plan sheets
and report exhibits and connection to individual GIS features (i.e. a georeferenced
polygon connecting to a specific plan sheet).
Task 4: Analysis of Collected Data
Data analysis tasks will generally include comprehensive analysis of all models, reports, record drawings
and GIS information to determine the accuracy and validity of each. In addition, Halff will evaluate the
current funding sources and consider alternative options for funding of future projects and studies. Halff
61Page
will also review the current drainage criteria and work with the City and BDD4 to recommend any potential
changes or clarifications that may be needed. Specific tasks relating to data analysis include the following:
a. H&H Model Assessment
Conduct a comprehensive evaluation of the hydrologic models for the major creeks and
their tributaries received. Halff will check the models for reasonableness of model
assumptions, rainfall inputs, loss parameters, hydrograph transform parameters, storage
assumptions, and results. In addition, comparisons will be made to the discharges in the
Effective FIS to ensure consistency. Any computational issues with the models will be
identified.
ii. Conduct a comprehensive evaluation of the hydraulic models for the major creeks and
their tributaries. Halff will check models for reasonableness of reach and cross section
layouts, section data, geometric parameters, including roughness, hydraulic structures,
and results. The steady flow data will also be checked for correctness and consistency
with the hydrologic models and/or Effective FIS.
iii. In those cases where hydrologic models are in HEC -1 or hydraulic models are in HEC -2, a
preliminary conversion to HEC-HMS/RAS will be done for evaluation. No significant
changes will be made to the models during Phase I of the MDP.
iv. Model results will be compared to the Effective DFIRM mapping data and the flood
insurance claim data provided and discrepancies will be identified. For flood insurance
claim data, Halff will compare the effective floodplains to specific claim locations to help
determine if the flooding is riverine or caused by a localized flooding source.
v. Halff will consider the drainage patterns and determine if the modeling tools utilized are
appropriate or if other tools, including unsteady 1D or 2D modeling are recommended.
b. Drainage Report and Record Drawing Analysis
Conduct a comprehensive evaluation of the LOMRs, CLOMRs, and drainage reports for
regional detention, channel improvements or major developments. A cursory review of
other drainage reports will be conducted to determine if the information provided
impacts the larger study. Halff will review the scope, assumptions, methodologies, and
recommendations of reports. If results were carried forward to design or construction,
Halff will compare with the construction or record drawings for consistency. Constructed
projects will be evaluated for consistency during the field verification phase, which will be
detailed below.
ii. Halff will review record or "as -built" drawings of constructed projects. Comparisons will
be made to on -the -ground information gathered during the field verification process and
discrepancies will be identified. Comparisons to the models for storage volume and
outfall capacity will also be conducted.
c. Master Plan and CIP Plan Analysis
i. A review of the current City of Pearland drainage plan (1998) will be conducted and its
assumptions, findings and recommendations considered.
ii. A review of the current Brazoria OD4 drainage plan (1997) will be conducted and its
assumptions, findings and recommendations considered.
7
iii. A review of the City of Pearland 2015-2019 CIP Plan will be conducted with a focus on the
drainage projects recommended. These projects will be included in the evaluation and
prioritization to be completed as part of Phase II.
d. Drainage Criteria Analysis
i. Review the current drainage criteria for both the City and BDD4. Discuss with the City
and BDD4 the general effectiveness of the criteria, areas of concern, clarifications, or
additional criteria that should considered with respect to the design procedure or land
use and zoning regulations.
e. Funding Analysis
i. Halff will assess the current sources of funding and determine if alternative means of
study and project funding are necessary and feasible. Long term sources of project and
study funding may include a Storm Water Utility (SWU), Storm Water Impact fees for
areas benefiting from CIP, such as detention or channel improvements, and others.
Task 5: Field Verification
Field verification tasks will include on-site investigation of all major detention ponds and outfall structures
into open channels. Halff will also evaluate the channels for general conformity with models assumptions
and identify any significant erosion hazards. Mobile GIS data collection technology will the utilized during
the process. Specific tasks relating to data analysis and field verification include the following:
a. Mobile GIS Map Development
i. Prior to the on-site reconnaissance process, Halff will configure a mobile map service for
us with the Halff GIS iOS app. This app is designed to support field data collection and is
available from the Apple App Store as a free download. The mobile map service allows
users to access GIS data in real time from iPhones and iPads. The Halff GIS iOS app
supports creating new data features, updating existing features, and referencing
supporting GIS data layers.
b. Field Data Collection
Halff will conduct site visits of all storm sewer outfalls, regional detention ponds, and
sections of the identified streams. Site visits will be conducted by two (2) persons, a
project engineer and an EIT. During the site visits, Halff will geo-locate all features,
photograph the feature, and include notes regarding the dimensions, conditions, etc. This
data will be entered into the Halff GIS iOS app, which is connected to the server in real
time through a cellular or Wi-Fi network.
ii. As features are photographed and documented, the status will be updated from "not
verified" to "verified". This designation will allow the City and BDD4 to continually track
the field verification progress using the Transparency Tools discussed above.
iii. Once the field verification process is complete, the GIS data developed will be evaluated
for completeness and correctness and finalized. The data will be provided to the City and
BDD4 as part of the final submittal.
81 Page
Task 6: Phase I Recommendations
The Phase I recommendations will include the development of a number of specific actions intended to
improve the existing data, modeling, funding, and drainage criteria. These will be discussed with the City
and BDD4 during a preliminary and final meeting, which are listed in Task 2. Specific tasks relating to the
Phase I Recommendations include the following:
a. Develop Phase I Recommendations
i. Identify any additional data necessary to begin work on Phase II, such as survey, additional
modeling, GIS information, etc.
ii. Determine what updates and changes need to be made to the existing conditions
modeling during Phase 11. Halff will attempt to utilize existing models to the maximum
extent practicable. Updates may include the use of more advanced modeling techniques
such as Unsteady and 2D modeling if necessary. Other updates may include modification
of development levels, updated terrain information, etc.
iii. Demonstrate the benefits of specific alternative funding sources such as Storm Water
Utilities, Storm Water Impact fees, grants, etc. Provide recommendations for further
exploring these options. Development and implementation of specific alternative funding
streams is NOT included in this scope of services.
iv. Recommend changes, additions, and/or clarifications to the existing drainage criteria.
This may include changes to specific design criteria, as well as policy updates aimed at
avoiding negative development impacts.
Task 7: Flood Protection Planning Grant Application
Preparation of the application for a Flood Protection Planning Grant (FPPG) to be submitted to the Texas
Water Development Board (TWDB). TWDB will advertise for the 2016 grants in the fall of 2015 and
applications will be due in early 2016. Development of the grant application will include the following
tasks:
a. Stakeholder Coordination
i. Meet with City staff to confirm the purpose of the FPP Study and clearly define the detail
study area located within the watershed basin.
ii. Define potential project stakeholders (i.e. City of Pearland, Brazoria Drainage District No.
4, etc.) within the watershed FPP Study.
iii. Meet with TWDB to coordinate the Grant application and confirm project objectives.
iv. Notify political subdivisions, agencies, authorities, and planning groups in the proposed
project area that an application for grant assistance is being submitted to the TWDB.
v. Obtain Letters of Support and/or Interlocal Agreements with project stakeholders.
b. Grant Application
i. Document the study needs and compile existing available leverage (LiDAR, H&H Models,
HWM's, Flood Records, SRL's ...etc.). This task will be completed as part of the data
collection and analysis tasks discussed above.
91Page
ii. Develop a project scope and budget for the FPP and define sources of funding (Cash
contribution, In -Kind, Interlocal Agreements, etc.)
iii. Prepare the Grant Application and submit to TWDB
Task 8: Phase I Submittal
The Phase I submittal will include the project deliverables; a detailed narrative discussing the data
collection and inventory process, compilation of all the data collected and evaluated, updated digital
information, including GIS, H&H models, photos, and recommendations for Phase II. Specific tasks relating
to the Phase I Submittal preparation include the following:
a. Digital Data Deliverable
i. Prepare the MDP Geodatabase for submittal. The Geodatabase will include the feature
classes relating to the model inventory and report/plan inventory developed as part of
Task 3 as well as the field data collected as specified in Task 5. Among other data fields,
ownership of features will be identified. Other relevant digital data collected will be
organized into the Geodatabase as well.
ii. Update delineations of all drainage basins located within the project areas using a polygon
feature. These will include delineations for the stream watershed as well as drainage
subbasins for contributing streams and ditches. These will be included in the
Geodatabase.
iii. Identify service areas for the major regional detention facilities, identifying the
contributing area using a polygon feature. The information will be included in the
Geodatabase.
iv. Map the 100- and 500 -year floodplains for Clear Creek on the Brazoria County side. Halff
will utilize the effective BFE's from the HCFCD study and map on the most current LiDAR
terrain surface. The information will be included in the Geodatabase.
v. Provide the full library of scanned documentation, including reports and record drawings.
The associated GIS features will be included in the Geodatabase.
vi. Provide all models collected as well as any model updates. The models will be catalogued
and include the location, date prepared, and any other information available. The
associated GIS features will be included in the Geodatabase. The evaluation will be
provided as part of the narrative; but notes will be included in the GIS.
vii. Provide all photos taken during the field verification process in .jpg format. Photos will
be compressed to a size not to exceed 1Mb. The associated GIS features will be included
in the Geodatabase.
b. Report Deliverable
i. Prepare a detailed report, including a narrative discussion the procedures and findings of
each task, relevant figures and tables, meeting notes and a log of project decisions.
Copies of the digital information will be included on CD/DVD with the report.
ii. A preliminary scope of services and fees for Phase II will be provided with the final report.
The scoping will be completed as part of the Flood Protection Planning Grant application
discussed in Task 7.
101 Page
Task 9: Quality Assurance/Quality Control
Each task will be subjected to internal QA/QC by a separate water resources team at Halff. Associated
documentation will be provided with the Final Phase I Report. Specific tasks relating to the QA/QC process
include the following:
a. QA/QC Procedures
i. The QA/QC program will include a multi-level approach to ensure that senior members
review, comment, and approve the completed work. Quality control check lists shall be
created for the data collection, GIS data development, and final report elements of the
work. Each checklist shall include milestone review events that describe the items to be
reviewed and include documentation of the comments by the reviewer and responses
from the Project Manager. All project materials presented to the City and BDD4 as draft
or final products will be accompanied by QA/QC certification. QA/QC will be performed
for the following specific tasks:
a. Data and Model Inventory — Including the data scans and associated
Geodatabase
b. Field Data Verification — Including notes and photos taken as well as the GIS
data developed in the field.
c. Phase I Report — Including the narrative, exhibits, and tables. The final digital
submittal will also be reviewed.
ii. The ENGINEER shall retain all work products generated and information gathered and
used during the course of the project. This includes, but is not limited to, base data as
well as intermediate work products.
111 Page
CITY OF PEARLAND & BRAZORIA DRAINAGE DISTRICT NO. 4
MASTER DRAINAGE PLAN
LEVEL OF EFFORT ESTIMATE
November 11. 2015
.Y `o
_
2
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z s
S'
4
Project Physes and Tasks'
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4
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N=
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6
0250.00
5200.00
5175.00
9150 00
5100.00
5150 00
5110 00
575.00
565.00
Hours
Task 1: Wagon Trail Road Drainage Evaluation
Review Drainage Report and Calculations
2
4
8
91.809
01.800
Topographic Survey
64
$9.607
59,600
Existing Cond8ions 2D Modeling
12
18
48
.1
510.200
510.200
Flood Reduction Alemaeves Analysis
8
16
40
08.302
58.300
Subtotal Task 1
0
22
0
38
96
64
0
8
0
$20,900
SO
529.900
Task 2: MDP Management 8 Coordination
Development of Project Mangement Plan
1
1;
4
53,350
53,350
Project Kickoff Meeting 8 Minutes (1)
2
..
7
2
4
52.010
550
52.060
Project Update Meetings 8 Minutes (6)
i..
12
4
55,880
5300
56,180
Preparation and Public Meeting (2)
2
8
4
4
54,250
5120
54.370
Project Coordination
..
4
52,900
52.900
Project Salus Reports (8)
..
8
51,320
51.320
Web Map Development
53.280
03.280
Srb1Mal Task 2
S,
18
22
8
0
10
16
16
S22 993
54/0
523,460
Task 3: Data Collection 8 Model Inventory
GIS Data Colectbn (Cay, 8OO4, FEMA, Etc.)
8
51 550
51,550
H&H Model Colection
8
SI 550
$1.550
Drainage Report and Record Drawings
a
1;
16
53.600
'4, CC
S3.700
Data Organization and GS Inventory
Digital Scan of Repons/P41ns
1
8
24
S2 860
52,860
Devebpnent of Goodatabase
1
8
8
51820
01,820
Dig0ae Feature Classes for Data
2
e
2
51.350
51,350
Digitize Feature Classes for Models
2
51.350
51.350
S,hto1al T448 3
:I
16
4
26
s8
0
( 12
24
514.080
5100
514.180
CITY OF PEARLAND & BRAZORIA DRAINAGE DISTRICT NO. 4
MASTER DRAINAGE PLAN
LEVEL OF EFFORT ESTIMATE
November 11, 2015
Project Phases and Tasks'
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Task 4: Analysis of Colloctod Data
0084 Model Assessment
Evaluate HBH Models
4
4
32
64
512.700
512.700
Convert Models to HEC-HMS/RAS
1
2
16
24
55,350
55,350
Compare Resins to FEMA Maps and Loss Info
1
4
8
51.600
51,600
Drainage Report and Record Drawing Assessment
f
8
40
80
515,800
815,800
Master Plan and CIP Evaluation
8
20
40
58,800
08.600
[range Cme6a Evaluation
..
It
16
8
55,400
55.400
F lending Assessment
4
8
6
54,000
54.900
S .n:Mar Task
4
28
30
I 13:
224
0
0
0
1.
554,350
50
354.350
Task 5: Field Verification
•L.
-
a
Mobile GIS Map Devodpmont
1
n
S 1.020
51.020
Field Data Coleabn/Documentation
F told Data Colleclnn
I t;
81,
?.(1
523 800
51100 00
024.400
GIS Data Review
4
4
8
53 080
53,080
Subtotal Task 5
0
21
8
80
80
0
10
16
0
027 900
5600
528.500
Task 8: Phase I Recommendations
Specify AddOnnal Data Needs
1
51 31,0
51.350
Recommend Updates to Existing ?skate's
1
8
l..
5.1 :03
S3.600
',recommend Alternative Funding Options
17
0
-.
Iti 000
27,800
Recommend Cetera Updates
.•
.
r,
0
> ,. ,:
55,650
0,610131 Task 6
0
20
20
7.1
40
0
0
0
0
S 18 400
SO
518.400
CITY OF PEARLAND & BRAZORIA DRAINAGE DISTRICT NO. 4
MASTER DRAINAGE PLAN
LEVEL OF EFFORT ESTIMATE
November 11, 2015
Project Pharos and Tasks'
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Task 7: Flood Protection Planning Grant
Slakeholder Coordmauon
2
66
4
1J
'1
54810
530000
85.110
0,481 6005841ton1
4
4
0
6
53.680
53.880
O Je50141 Task?
3
10
10
12
18
0
0
0
6
58.480
5300
88,790
Task 6: Phase I Submittal
Digital DMa Submetal
Complete Final Geodatabase1
2
.,
7
4
51.420
51.420
Update Drainage Basin Delineaton1
4
1.
1
02,475
82.475
Delineate Regional Detention Service Areas1
1
n
1
51,225
51,225
Clear Creek Floodplain Mappng1
2
8
51.300
61.300
Prepare Grattage RepoNRecord Draxnng Library1
2
5900
5900
Prepare Model Catalogue
2
5700
8700
Prepare Photo Catalogue
2
8
81,100
81,100
Report Preparation
Narrative Development
. 4
,.•
16
57 065
57,065
Exhibit Prepratbn
4
16
53.130
53,130
Tables 6 Figures Preparatbn
4
8
02.330
52,330
Subtotal Task8
0
:t7
0
27
92
0
2
6
021645
.,..
821,650
Task 9: Quality Assurance/Quality Control
Data and lAodel Inventory QAi0C1:•
1
54.640
54.640
Field Data Vedic -aeon QAIQC
7
1.
1
54.640
64,640
Phase 1 Report 00.QC
7
81,
1
54,640
64.640
Subtotal Task9
6
24
36
0
0
12
0
0
513,920
50
513,920
PROJECT TOTALS
23
238
126
363
606
64
36
58
51
8211.675
81.470
8213,150
SAAt4•HOUR PERCENTAGES
1.5%
152%
81%
23 7%
387%
4 1%
2.3%
3.7%
33%
1 aaDaiOrtInV
•(u
Toro
Jan
-3' L:;m5n
LEGEND
111=Pearlen0r8004 MDPArea
amain DIM
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TL1 1. HOUSTON
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CITY OF PEARLAND
BRAZORIA DD4
MASTER DRAINAGE PLAN
PROJECT LOCATION
MAP
October 2015
0 4.000 8,000 16.000
Feet
1 inch = 8.000 feet
Notes:
1) Aortal imagery fol Pearland. T%
and surrounding ares provided by
Landiscor 2014
21 Project area includes the Cool
Peanaud and Brant. 004 Porton,
of other cies, InCIuding Brookside
village. Manvel. Iowa Colony arw
Alvis are also located wdMn the
p107001 area es well.
!!E HALFF
NALFF ASSOCIATES. INC.
14800 SAINT MARYS LN. SUITE 141'
HOUSTON, TX 70079.2943
w^Nw HAI , COM
Exhibit C
MBCO
Engineering, LLC.
MOSS 1 BLETSCH CRENEK OLLER
IEA
WAGON TRAIL ROAD DITCH DRAINAGE ANALYSIS
PROJECT SCOPE
The City of Pearland Public Works employed MBCO Engineering, LLC. (MBCO) to perform the drainage analysis of
the Wagon Trail Road ditches from Mary's Creek to FM 518 and along FM 518 from west of Wagon Trail Road to the
Corrigan Creek By -Pass. The project scope consisted of the following steps to perform the ditch drainage analysis:
1. Collect Topographical Survey Data and LIDAR data of the project area along Wagon Trail Road, FM 518,
Hatfield Road, Mary's Creek and Corrigan Creek By -Pass.
2. Analyze the data to determine drainage areas, flow patterns, and size the existing ditches to help with
future drainage
3. Develop letter report and recommendations for the City of Pearland Public Works to identify methods that
will improve the drainage along Wagon Trail Road.
EXISTING CONDITIONS
The project area is a two lane asphalt roadway with open ditch drainage and a 60 foot right of way. The limits of
Wagon Trail Road with respect to the project area is from Mary's Creek to FM 518. The distance of the project area
along Wagon Trail Road is approximately 4,725 linear feet of roadway which equates to approximately 9,450 linear
feet of ditches. The project area has cross streets and drainage which include: Figland Street, Fite Road, Bardet
Street, Ochoa Road, Cantu Road and Josephine Street. The cross streets are 2 lane asphalt roadways with open ditch
drainage. The project area included 200 linear feet of each of the cross streets.
The existing drainage along Wagon Trail Road travels north and south with the high point being south of Bardet
Street at approximate Station 17+50. There are seventy (70) existing culverts that convey the drainage along Wagon
Trail with sizes varying from 15 inch to 30 inch diameter pipes and the material of the pipes vary from corrugated
metal to HDPE to reinforced concrete pipe. Several of the culverts do not meet the current City of Pearland Standard
minimum culvert size.
Through meetings with stakeholders in the project area, the area has experienced flooding during extreme rain
events since the beginning of the year. Observations during some of the recent rain events show that the FM 518
ditch and the west ditch north of Bardet to FM 518 experience the worst back-up and potential for area flooding
within the project area. There was also structural flooding coming out of the inlets on both FM 518 and Wagon Trail
as well as street flooding due to the severity of the storms.
TOPOGRAPHICAL SURVEY AND CULVERT FLOW SPREADSHEET
The first part of the scope of services was to gather data through the use of survey equipment to develop the digital
terrain model and pick up the topographical features of the project area. MBCO sent out a three man crew with two
GPS Trimble units to collect the existing terrain of the project area. The surveying took 4 days in the field. The crew
collected the ditch along the south side of FM 518 and along both sides of Hatfield and the first 400 linear feet of
1
MBCO
Engineering, LLC.
MOSS 1 BLETSCH 1 CRENEK I OLLER
IEA
Wagon Trail on the first day. On the second day the crew collected the ditches along Josephine, Ochoa, Bardet, Fite
and the next 3000 linear feet of Wagon Trail. The crew picked up the rest of Wagon Trail and the topography of
Mary's Creek at the end of Wagon Trail and the cross sections along Corrigan Creek By -Pass. The final day the team
collected the inverts of the storm sewers and collected some missing data requested by the engineer.
Once we had all the field data, MBCO processed and created a 3 dimensional topographical survey file and developed
a digital terrain model (DTM) of the project area. Once the topographical survey was completed, road alignments
were created for the project and all the culverts were assigned a Station ID. The Station IDs and the survey allowed
the Engineer to input the following data into the Culvert Flow Spreadsheet (See Exhibit 1):
• Upstream and downstream flow line elevations of each culvert
• Station location of the each culvert
• Distance between each culvert
• Culvert Size and material
Based on the information above the Culvert Flow spreadsheet computed the slope (%) and direction
(North/South/East/West) of each culvert and the slope (%) and direction (North/South/East/West) of the ditches
between each culvert. This will allow the City of Pearland (City) to look at the entire project and determine which
culverts are in need of adjustment due to settlement and/or age of culvert. This data also allows the City to have a
snapshot on the flow patterns of the existing ditches and identify areas of potential ponding due to contraflow of
the ditch because of a culvert sloped in the wrong direction and/or slope.
The second purpose of the Culvert Flow spreadsheet is to provide upstream and/or downstream flow lines to make
the corrections to the existing culverts to change the slopes on the ditches to create improved flow in the ditches.
The culvert sizes will be evaluated in the drainage analysis defined in the next section and sizes may be adjusted in
the Culvert Flow spreadsheet based on the findings of the Drainage Analysis to improve ditch capacity and flow.
DRAINAGE ANALYSIS
The purpose of the drainage analysis is to determine the existing flow patterns along Wagon Trail, quantify peak
discharges to the roadside ditches, and determine proposed driveway culvert sizes. The drainage analysis was
performed in accordance with the City of Pearland Enqineerinq Desiqn Criteria Manual, dated June 2007. Peak runoff
discharges and proposed driveway culvert capacities were analyzed using a 3 -year storm event. The following is a
detailed summary of the drainage analysis along Wagon Trail.
Drainage Areas and Flow Patterns
Drainage areas were delineated using a combination of 2008 LiDAR based contour mapping as provided by the City,
topographical survey data, and field observations. Survey data collected along Wagon Trail provided flow line
elevations for the existing ditches and driveway culverts. This survey information was used to provide a more
detailed examination of the flow patterns within the existing Wagon Trail ROW and to aid in the delineation of the
drainage areas. A thorough site visit was conducted on July 22, 2015 to verify the existing drainage area boundaries,
flow patterns, and land use conditions.
2
MBCO
Engineering, LLC.
MOSS 1 BLETSCH 1 CRENEK OLLER
IEA
The land use of the contributing drainage areas is a mixture of commercial, residential, and open grassy areas. The
contributing drainage areas are relatively flat and the drainage patterns consist of overland sheet flow to Wagon
Trail. The roadside ditches along Wagon Trail collect the runoff from the contributing areas and convey the runoff
to two outfall points located at FM 518 and Mary's Creek. An existing drainage divide within the roadside ditches is
located near Bardet Street. From this drainage divide, the existing roadside ditches drain north to FM 518 and south
to Mary's Creek. For the purpose of this drainage analysis, there are a total of four drainage outfall points. These
four outfall points account for the ditches on the east and west side of Wagon Trail that drain to FM 518 and Mary's
Creek. The outfall points are identified as A, B, C, and D. The drainage area ID's used for this analysis are named
according to their respective outfall location. The drainage area map is provided as Exhibit 2.
Computed Peak Discharges
Peak runoff discharges were computed using the Rational Method. The Rational Method parameters include the
drainage area, runoff coefficient (C -Value), time of concentration, and rainfall intensity. Runoff coefficients for the
Wagon Trail roadway and contributing areas were based on current land use conditions. The offsite contributing
drainage areas development types and impervious cover was determined by using aerial photography. The
impervious cover along Wagon Trail was determined using topographic survey data. The C -Values selected for the
offsite contributing areas were obtained from Chapter 5 of the COPEDCM and are listed Table 1 below.
Table 1- Rational Method Runoff Coefficients "C -Values"
Land Use Description
C -value
Large Lot Residential
0.40
Small Lot Residential
0.50
Commercial
0.85
Wagon Trail Pavement
0.90
Open Grassy Areas
0.20
Time of concentrations for the Rational Method were determined by dividing the flow into two segments: overland
and ditch flow. For the overland flow segment, an assumed velocity of 0.50 fps was used and a velocity of 1.0 fps
was assumed for the ditches. Each flow segment travel time was summed to determine the total time of
concentration for each drainage area. A 15 -minute minimum time of concentration was considered for all drainage
areas.
Rainfall intensity calculations for the Rational Method are dependent on the time of concentration. Rainfall Intensity
Duration Frequency Curves (IDF) obtained from the City of Pearland Drainage Criteria Manual were used to
determine rainfall intensities for each drainage area.
The peak runoff discharges were calculated for a 3 -year storm event. Table 2 provides a summary of the peak
discharges for each drainage area.
Driveway Culverts
The driveway culverts were evaluated to determine the proposed sizes based on hydraulic capacity in comparison
with each driveway culverts peak discharge. The driveway culverts were determined based on full flow capacity
3
MBCO
Engineering, LLC.
moss' BLETSCH CRENEK I OLLER
IEA
using a max size of 24" RCP due to the shallow ditches. An 18" RCP was set as the minimum size for this analysis.
Multiple culverts were used in order to meet the hydraulic capacities. In some cases, more than two culverts were
used even though this will most likely not fit within the ROW of Wagon Trail. The goal is to provide the flow area
that is required for each of the driveway culverts needed to satisfy the hydraulic capacity requirements. Table 3
provides a summary of the driveway culvert sizes.
Table 2 - Summary of Peak Discharges
3 -Year Storm Event
NODE ID
CUMULATIVE
AREA
(ac)
TC
(minutes)
CUMULATIVE
C VALUE
INTENSITY
(in/hr)
CUMULATIVE
DISCHARGE
(cfs)
DITCH A
A-1
6.15
27.37
0.83
4.09
20.97
A-2
5.90
25.98
0.84
4.20
20.69
A-3
4.84
23.60
0.84
4.40
17.79
A-4
4.07
21.93
0.84
4.56
15.52
A-5
3.25
20.06
0.84
4.75
12.90
A-6
2.79
19.04
0.84
4.86
11.36
A-7
2.25
17.69
0.84
5.02
9.47
A-8
1.32
15.65
0.84
5.28
5.88
A-9
0.78
15.00
0.84
5.37
3.50
DITCH B
B-1
22.91
41.45
0.46
3.3
34.90
B-2
22.81
40.48
0.46
3.3
34.77
B-3
22.51
39.66
0.46
3.34
34.70
B-4
22.15
38.64
0.46
3.39
34.60
B-5
21.60
38.09
0.46
3.47
34.46
B-6
21.6
37.11
0.46
3.47
34.45
B-7
21.29
36.25
0.46
3.52
34.36
B-8
18.85
35.14
0.45
3.58
30.69
B-9
15.84
32.92
0.45
3.71
26.35
B-10
15.52
31.71
0.45
3.78
26.29
B-11
9.62
31.18
0.42
3.82
15.31
B-12
2.96
29.18
0.42
3.95
4.96
B-13
2.81
27.73
0.42
4.06
4.80
B-14
2.72
26.76
0.42
4.13
4.70
B-15
2.68
26.34
0.42
4.17
4.65
B-16
2.62
25.68
0.42
4.22
4.59
B-17
2.39
23.11
0.41
4.44
4.34
B-18
1.74
21.54
0.4
4.59
3.20
B-19
0.78
18.49
0.38
4.92
1.46
B-20
0.19
15
0.27
5.37
0.28
4
MBCOIEngineering, LLC.
MOSS I BLETSCH CRENEK oLLF_R
Table 2 - Summary of Peak Discharges (Cont.)
IEA
NODE ID
CUMULATIVE
AREA
(ac)
TC
(minutes)
CUMULATIVE
C VALUE
INTENSITY
(in/hr)
CUMULATIVE
DISCHARGE
(cfs)
DITCH C
C-23
57.89
61.89
0.37
2.55
54.33
C-22
48.21
57.29
0.38
2.68
49.12
C-21
47.31
56.73
0.38
2.70
48.44
C-20
46.10
55.89
0.38
2.72
47.56
C-19
41.60
54.16
0.38
2.80
43.92
C-18
41.48
53.72
0.38
_ 2.80
43.78
C-17
41.30
53.26
0.38
2.80
43.57
C-16
40.48
51.65
0.38
2.86
43.43
C-15
38.98
49.24
0.38
2.94
43.00
C-14
33.84
46.91
0.38
3.03
38.58
C-13
28.91
45.38
0.38
3.09
33.95
C-12
28.49
44.42
0.38
3.13
33.86
C-11
27.69
42.58
0.38
3.21
33.68
C-10
25.39
41.29
0.39
3.27
31.94
C-9
22.98
39.33
0.38
3.36
29.53
C-8
20.19
34.59
0.38
3.61
27.87
C-7
19.81
33.44
0.38
3.68
27.84
C-6
12.93
33.00
0.46
3.70
22.22
C-5
7.86
21.41
0.55
4.61
19.84
C-4
6.47
20.06
0.58
4.75
17.74
C-3
3.65
17.25
0.71
5.07
13.16
C-2
2.36
15.93
0.83
5.24
10.28
C-1
1.65
15.00
0.84
5.37
7.43
DITCH D
D-21
22.17
52.59
0.46
2.83
28.55
D-20
19.67
50.72
0.45
2.89
25.79
D-19
18.8
49.26
0.46
2.94
25.22
D-18
18.31
48.35
0.46
2.97
24.92
D-17
17.92
47.69
0.46
3
24.66
D-16
16.69
45.36
0.46
3.09
23.87
D-15
15.37
44.67
0.47
3.12
22.43
D-14
12.72
43.76
0.48
3.16
19.34
D-13
11.6
40.17
0.49
3.32
18.78
D-12
10.71
39.12
0.5
3.37
17.86
D-11
8.34
36.55
0.48
3.5
14.08
0-10
6.9
35.02
0.41
3.58
10.12
0-9
5.06
32.63
0.4
3.73
7.50
5
MBCOJEngineering, LLC.
MOSS ( BLETSCH CRENEK OLI E_k
Table 2 - Summary of Peak Discharges (Cont.)
IEA
NODE ID
CUMULATIVE
AREA
(ac)
TC
(minutes)
CUMULATIVE
C VALUE
INTENSITY
(in/hr)
CUMULATIVE
DISCHARGE
(cfs)
DITCH D
0-8
2.98
30.57
0.42
3.86
4.86
D-7
2.83
28.99
0.42
3.97
4.69
D-6
2.72
27.92
0.41
4.05
4.55
D-5
2.54
26.03
0.41
4.19
4.35
D-4
2.24
23.58
0.41
4.4
4.07
D-3
1.3
20.9
0.41
4.66
2.49
D-2
0.64
17.5
0.41
5.04
1.34
D-1
0.24
15
0.41
5.37
0.54
Table 3 - Summary of Driveway Culverts
3 -Year Storm Event
ID
STATION
CUMULATIVE
AREA
(ac)
CUMULATIVE
DISCHARGE
(cfs)
CULVERT
N -VALUE
CULVERT
SLOPE
(FT/FT)
CULVERT
QUANTITY
PIPE
DIAMETER
(FT)
CULVERT
CAPACITY
(CFS)
DITCH A
A-1
10+53.48
6.15
20.97
0.013
0.002
3
2
30.43
A-2
11+68.49
5.90
20.69
0.013
0.002
3
2
30.43
A-3
13+58.70
4.84
17.79
0.013
0.002
2
2
20.29
A-4
14+85.40
4.07
15.52
0.013
0.002
2
2
20.29
A-5
16+22.77
3.25
12.90
0.013
0.002
2
2
20.29
A-6
16+98.81
2.79
11.36
0.013
0.002
2
2
20.29
A-7
17+88.60
2.25
9.47
0.013
0.002
1
2
10.14
A-8
18+94.92
1.32
5.88
0.013
0.002
1
2
10.14
A-9
19+51.43
0.78
3.50
0.013
0.002
1
2
10.14
DITCH B
8-1
12+38.73
22.91
34.90
0.013
0.002
4
2
40.58
B-2
13+29.61
22.81
34.77
0.013
0.002
4
2
40.58
B-3
14+05.98
22.51
34.70
0.013
0.002
4
2
40.58
B-4
15+00.58
22.15
34.60
0.013
0.002
4
2
40.58
B-5
15+52.60
21.60
34.46
0.013
0.002
4
2
40.58
B-6
16+43.12
21.6
34.45
0.013
0.002
4
2
40.58
B-7
17+23.15
21.29
34.36
0.013
0.002
4
2
40.58
B-8
18+24.57
18.85
30.69
0.013
0.002
4
2
40.58
B-9
20+19.54
15.84
26.35
0.013
0.002
3
2
30.43
B-10
21+25.62
15.52
26.29
0.013
0.002
3
2
30.43
B-11
21+65.87
9.62
15.31
0.013
0.002
2
2
20.29
8-12
22+80.94
2.96
4.96
0.013
0.002
1
2
10.14
6
MBCO
Engineering, LLC.
MOSS 1 BLETSCH , CRENEK ; OLLER
Table 3 - Summary of Driveway Culverts (Cont.)
IEA
ID
STATION
CUMULATIVE
AREA
(ac)
CUMULATIVE
DISCHARGE
(cfs)
CULVERT
N -VALUE
CULVERT
CULVERT
SLOPE QUANTITY
(FT/FT) 1
PIPE
DIAMETER
(FT)
CULVERT
CAPACITY
(CFS)
DITCH B
B-13
23+65.99
2.81
4.80
0.013
0.002
1
2
10.14
B-14
24+21.10
2.72
4.70
0.013
0.002
1
1.5
4.71
B-15
24+46.45
2.68
4.65
0.013
0.002
1
1.5
4.71
8-16
24+85.16
2.62
4.59
0.013
0.002
1
1.5
4.71
8-17
26+27.73
2.39
4.34
0.013
0.002
1
1.5
4.71
8-18
27+06.97
1.74
3.20
0.013
0.002
1
1.5
4.71
8-19
28+42.37
0.78
1.46
0.013
0.002
1
1.5
4.71
B-20
29+43.09
0.19
0.28
0.013
0.002
1
1.5
4.71
DITCH C
C-23
56+26.06
57.89
54.33
0.013
0.002
6
2
60.87
C-22
51+67.87
48.21
49.12
0.013
0.002
5
2
50.72
C-21
51+12.10
47.31
48.44
0.013
0.002
5
2
50.72
C-20
50+29.39
46.10
47.56
0.013
0.002
5
2
50.72
C-19
48+60.56
41.60
43.92
0.013
0.002
5
2
50.72
C-18
48+17.50
41.48
43.78
0.013
0.002
5
2
50.72
C-17
47+72.61
41.30
43.57
0.013
0.002
5
2
50.72
C-16
46+16.11
40.48
43.43
0.013
0.002
5
2
50.72
C-15
43+82.47
38.98
43.00
0.013
0.002
5
2
50.72
C-14
41+61.04
33.84
38.58
0.013
0.002
4
2
40.58
C-13
40+20.16
28.91
33.95
0.013
0.002
4
2
40.58
C-12
38+77.79
28.49
33.86
0.013
0.002
4
2
40.58
C-11
37+07.80
27.69
33.68
0.013
0.002
4
2
40.58
C-10
35+89.80
25.39
31.94
0.013
0.002
4
2
40.58
C-9
34+14.98
22.98
29.53
0.013
0.002
3
2
30.43
C-8
29+92.70
20.19
27.87
0.013
0.002
3
2
30.43
C-7
28+91.23
19.81
27.84
0.013
0.002
3
2
30.43
C-6
28+34.06
12.93
22.22
0.013
0.002
3
2
30.43
C-5
26+04.06
7.86
19.84
0.013
0.002
2
2
20.29
C-4
24+96.86
6.47
17.74
0.013
0.002
2
2
20.29
C-3
22+86.30
3.65
13.16
0.013
0.002
2
2
20.29
C-2
21+91.18
2.36
10.28
0.013
0.002
2
2
20.29
C-1
21+04.90
1.65
7.43
0.013
0.002
1
2
10.14
DITCH D
D-21
56+40.00
22.17
28.55
0.013
0.002
3
2
30.43
D-20
53+91.00
19.67
25.79
0.013
0.002
3
2
30.43
D-19
52+66.53
18.8
25.22
0.013
0.002
3
2
30.43
7
MBCO
Engineering, LLC.
moss! BLETSCH j CRENEK 1 OLLER
Table 3 - Summary of Driveway Culverts (Cont.)
IEA
ID
STATION
CUMULATIVE
AREA
(ac)
CUMULATIVE
DISCHARGE
(cfs)
CULVERT
N -VALUE
CULVERT
SLOPE
(FT/FT)
CULVERT
QUANTITY
PIPE
DIAMETER
(FT)
CULVERT
CAPACITY
(CFS)
DITCH D
D-18
51+89.96
18.31
24.92
0.013
0.002
3
2
30.43
D-17
51+33.69
17.92
24.66
0.013
0.002
3
2
30.43
D-16
49+37.45
16.69
23.87
0.013
0.002
3
2
30.43
D-15
48+79.74
15.37
22.43
0.013
0.002
3
2
30.43
D-14
48+07.16
12.72
19.34
0.013
0.002
2
2
20.29
D-13
45+22.82
11.6
18.78
0.013
0.002
2
2
20.29
D-12
44+39.60
10.71
17.86
0.013
0.002
2
2
20.29
D-11
42+47.32
8.34
14.08
0.013
0.002
2
2
20.29
D-10
41+38.68
6.9
10.12
0.013
0.002
1
2
10.14
0-9
39+78.95
5.06
7.50
0.013
0.002
1
2
10.14
0-8
38+62.54
2.98
4.86
0.013
0.002
1
2
10.14
D-7
37+72.64
2.83
4.69
0.013
0.002
1
1.5
4.71
D-6
37+09.96
2.72
4.55
0.013
0.002
1
1.5
4.71
D-5
36+05.19
2.54
4.35
0.013
0.002
1
1.5
4.71
D-4
34+71.00
2.24
4.07
0.013
0.002
1
1.5
4.71
D-3
32+72.48
1.3
2.49
0.013
0.002
1
1.5
4.71
0-2
31+34.52
0.64
1.34
0.013
0.002
1
1.5
4.71
0-1
30+49.54
0.24
0.54
0.013
0.002
1
1.5
4.71
RECOMMENDATIONS
The Wagon Trail Road drainage system is under sized and is in need of repair. There is a large amount of drainage
area that is coming to the open ditch system that discharges into Mary's Creek and into the FM 518 ditch system.
As shown in Table 3 in the drainage analysis section, the amount of pipes needed at each culvert crossing exceeds
the size the ditch currently allows and would require additional right of way to be put in place.
The recommendations of this report are two fold and are described below:
Short Term/ Immediate Recommendations
The original design frequency for the ditches in this area are unknown. For the purpose of the engineering
calculations in this report it is assumed that the Wagon Trail ditches can hold a 3 -year frequency storm and the
ditches along FM 518 can hold a 5 -year frequency storm to stay consistent with the City of Pearland Storm Sewer
Design Criteria, Chapter 5, Section 5.5.2, Design of Storm Sewers. The flooding issues will not be resolved without a
major capital improvement initiative that will increase the storm frequency that the systems can handle. Any storms
that exceed the current design frequencies will result in the surrounding ditches and storm sewer systems to flow
at or above capacity. The short term and immediate recommendation is to make sure that the ditches on Wagon
8
MBCO
Engineering, LLC.
MOSS 1 BLETSCH CRENEK I OLLER
IEA
Trail and the south ditch along FM 518 from Wagon Trail to the Corrigan By -Pass are included in the City's ditch
maintenance program and are adjusted by referring to the Culvert Flow spreadsheet. Ditches may also be widened
in the field to help increase the storage capacity and allow for the installation of additional culverts but these
modifications need to be field engineered by the Engineer of Record and will only improve the system's efficiency
but not correct the current situation. Based on the results from Table 3 and the recommendations of the culvert
improvements in the Exhibit 1; Exhibits 3 and 4 are the preliminary installation costs for Wagon Trail Road culverts.
These costs do not include any recommended adjustments on cross streets as they will need to be evaluated and
adjusted on an as need basis to improve the drainage on Wagon Trail Road.
Additionally, stakeholders in the area should evaluate their individual property's drainage systems for deficiencies
and low spots that can and will cause localized spot flooding independent of the Drainage District's or City's drainage
systems.
Long Term Recommendations
The long term recommendation is to extend the current study into a Phase II Study focusing on the possibility of
diverting some of the existing drainage areas away from the Wagon Trail ditch system and redirecting it to the
Corrigan Creek By -Pass System. This will allow the team to reanalyze the capacity needs of the Wagon Trail ditch
system and ultimately reduce any potential for future flooding. This study should look at the diversion of the
drainage on Cantu, Ochoa, and Fite and the diversion of drainage on Hatfield and possibly from FM 518 into Corrigan
Creek By -Pass.
Should the Phase II Study confirm that diversions will provide needed relief to the Wagon Trail Ditch System then
Phase III, which will be the design of the diversions identified in the Phase II Study, should be implemented.
MBCO and IEA are pleased to provide the City of Pearland Public Works this report and should you have any
questions or concerns please contact Brock Crenek, PE at brock.crenek@mbcoengineering.com or via phone at 832-
607-2047. Again thank you for the opportunity to help better the City of Pearland and we look forward to working
with you in the future.
EXHIBITS
Exhibit 1— Culvert Flow Calculations
Exhibit 2 — Drainage Area Map
Exhibit 3 — RCP Installed Cost Estimate
Exhibit 4 — HDPE Installed Cost Estimate
9
Exhibit D
Wagon Trail Road Drainage Improvement from Bardet Road to the
outfall at Fite Road Bridge
Prepared By: Engineering and Project Department
City of Pearland
3523 Liberty Dr
Pearland, Texas 77581
November 5, 2014
Wagon Trail Drainage Improvement from Bardet Road to the outfall at Fite Road Bridge
Introduction
Wagon Trail between FM 518 and Fite Rd can divided into two segments in terms of drainage area
boundary. Based on the survey, lidar, field visit and the drainage report titled "Wagon Trail Road Ditch
Drainage Analysis" dated September 16, 2015 and prepared by MBCO Engineering, LLC , the area north
of Bardet Rd drains into FM 518 roadside ditch whereas the area south of Bardet Rd drains into roadside
ditch of Fite Rd through a 24" CMP across Wagon Trail. Based on the drainage report, discussion within
the city as well as using engineering judgment, it will not be wise to initiate the drainage improvement
on the north side of Bardet Rd without a good draiange master plan to take care of flooding issue near
FM 518 as well as Cantu Road and Ocho Road.
The city revisited the drainage report prepared by MBCO and revised the drainage calculation to design
culvert size along Wagon Trail between Bardet Rd and Fite Rd. In addition, gis survey was done along
Fite Rd between the Wagon Trail/ Fite Rd intersection and east outfall near the Fite Rd bridge.
Findings:
1. Approximately 19.83 Acres of drainage area is draining into Fite Rd system from west side of
Wagon Trail through a 24" CMP which is at the condition of failure due to corrosion and as well
as silt deposit.
2. Approximately 24.76 Acres of drainage area is draining into Fite Rd system from east and west
side of Wagon Trail from the intersection with culvert pipe as small as 18" diameter.
3. The existing pipe size varies between 15" diameters to 24" diameter with the some of the pipes
installed reverse flow direction.
Proposed Solutions:
1. The culvert size along east and west side Wagon Trail as well as north side of Fite Rd has been
designed to handle 3 -year storm event.
2. Minimum pipe size is kept as 24" diameter to increase the capacity of the culvert. The culverts
along north side of Fite Rd are designed as 36" diameter.
3. Majority of culvert size along west side of Wagon trail as well as the cross culvert across Wagon
Trail has been increased to 30" diameter.
Limitations:
1. Proposed recommendation will improve the drainage condition of the area but may not be able
to flood proof the area as the system is designed for 3 -year storm event. It is expected to see
some temporary ponding in the vicinity of drainage ditch during higher storm event (10 -year,
100- year and above).
1
Wagon Trail Drainage Calculation
Based on MBCO Drainage Area divide version 9/16/2015
System D
Total drainage area from D1 to D7 up to Fite Rd on east side
Redirect drainage area B-15 to system D
New Total Area
Length of overland flow
Length of ditch flow
Overland Flow velocity
Ditch flow velocity
Time of concentration
Rainfall intensity (3 -yr DD4 criteria)
Runoff coefficient (from MBOC report)
Peak discharge
System C
Total drainage area from C1 to C6 up to Fite Rd
DA C-6 essentially flow south to north through 24" RCP. So, it is
assumed to be a part of Fite Road North ditch system. MBCO's cal
for DA C-6 appears to be erroneous (5.07 ac where as it should be
about 1.5 AC)
New Total Area
Length of overland flow
Length of ditch flow
Overland Flow velocity
Ditch flow velocity
Time of concentration
Rainfall intensity (3 -yr DD4 criteria)
Runoff coefficient (from MBCO report)
Peak discharge
Routing of System C and System D
Drainage Area
Time of concentration (greater of Sys C and Sys D
Rainfall intensity (3 -yr DD4 criteria)
Runoff coefficient (large residential lot with roadway)
Peak Discharge
4.28 AC
0.65 AC
4.93 AC
360 FT
950 FT
0.5 fps
1 fps
33.83 min
3.72 inch/hr
0.43
7.89 cfs
19.83 AC
19.83 AC
630 FT
950 FT
0.5 fps
1 fps
36.08 min
3.6 inch/hr
0.31
22.13 cfs
24.76 AC
36.08 min
3.6 inch/hr
0.35
31.198 cfs
Estimate of Pipe Capacity for Wagon Trail Ditch Improvement
D (ft)
A
R
s
Pipe Ca. Q
1.5
1.76715
0.375
0.0015
_ 4.08
2
3.1416
0.5
0.0015
9.52
2.5
4.90875
0.625
0.0015
15.93
3
7.0686
0.75
0.0015
25.90
1.5
1.76715
0.375
0.002
4.71
2
3.1416
0.5
0.002
10.99
2.5
4.90875
0.625
0.002
18.39
3
7.0686
0.75
0.002
29.91
1.5
1.76715
0.375
0.001
3.33
2
3.1416
0.5
0.001
7.77
2.5
4.90875
0.625
0.001
13.01
3
7.0686
0.75
0.001
21.15
Ditch Capacity
W H
8
9
2.308391
3.029451
3.244954
3.664342
2.6655
3.498109
3.74695
4.231218
1.884793
2.473537
2.649494
2.991923
A P R s v Q
6 48 28 1.714286 0.001 5.609098 269.2367
4 36 26 1.384615 0.0009 4.260064 153.3623
H 2.5
Cd 0.64
D 0.5
A 0.19635
Q 1.593754 cfs
Culvert Pipe Size Estimate for Wagon Trail Drainage Improvement
System
Pipe ID
Pipe dia
(inches)
Actual
Length (ft)
Length to
ordered (ft)
D
D1
24
30
30
D2
24
26
30
D3
24
26
30
D3A
24
25
30
D4
24
28
30
D5
24
28
30
D6
24
26
30
D6A
24
30
30
D7
24
25
30
C
Cl
24
50
54
C2
24
55
30
C3
30
48
48
C4
30
_27
30
C5
30
39
42
E
El
36
30
30
E2
36
33
36
E3
36
29
30
E4
36
29
30
E5
36
29
30
Across Wagon Trail
30
40
42
Total
24
349
354
30
154
162
36
150
156
653 672
Assumption: No replacement of the existing SET and 36" from SET to inlet.
MBCO
Engineering, LLC.
MOSS l BLETSCH I CRENEK (OILER
Table 2 - Summary of Peak Discharges
3 -Year Storm Event
IEA
CULVERT ID
CUMULATIVE
AREA
(ac)
TC
(minutes)
CUMULATIVE
C VALUE
INTENSITY
(in/hr)
CUMULATIVE
DISCHARGE
(cfs)
DITCH A
A-1
14.02
39.36
0.66
3.36
31.09
A-2
13.77
38.09
0.66
3.42
31.08
A-3
12.7
35.98
0.65
3.53
29.14
A-4
11.94
34.55
0.64
3.61
27.59
A-5
11.11
32.98
0.62
3.71
25.56
A-6
10.65
32.1
0.61
3.76
24.43
A-7
10.11
31.04
0.6
3.83
23.23
A-8
8.64
29.04
0.56
3.96
19.16
A-9
6.21
26.87
0.45
4.13
11.54
A-10
5.51
25.57
0.41
4.23
9.56
A-11
4.22
24.13
0.41
4.35
7.53
A-12
1.4
20
0.41
4.75
2.73
DITCH B
B-1
21.16
35.52
0.47
3.56
35.73
B-2
21.06
34.54
0.47
3.61
35.73
8-3
20.77
33.73
0.47
3.66
35.73
B-4
20.4
32.72
0.47
3.72
35.67
B-5
19.85
31.19
0.46
3.82
34.88
8-6
19.55
30.34
0.46
3.87
34.80
B-7
17.11
29.22
0.46
3.95
31.09
B-8
14.1
27
0.45
4.12
26.14
8-10
7.88
24.95
0.42
4.28
14.17
B-11
1.22
22.65
0.46
4.49
2.52
B-12
1.07
20.88
0.45
4.66
2.24
B-13
0.98
19.74
0.45
4.78
2.11
8-14
0.87
18.37
0.45
4.94
1.93
8-15
0.65
15
0.43
5.37
1.50
DITCH C
C-18
50.02
65.59
0.34
2.46
41.84
C-17
40.35
60.7
0.35
2.58
36.44
C-16
39.44
60.1
0.35
2.6
35.89
C-15
38.24
59.21
0.34
2.63
34.19
C-14
33.74
57.33
0.34
2.69
30.86
C-13
33.61
56.86
0.34
2.69
30.74
C-12
33.43
56.36
0.34
2.71
30.80
C-11
32.62
54.62
0.33
2.76
29.71
C-10
31.11
52.02
0.33
2.85
29.26
C-9
25.97
49.45
0.32
2.93
24.35
C-8
21.05
47.74
0.32
3
20.21
C-7
20.62
46.6
0.32
3.04
20.06
C-6
19.83
44.52
0.31
3.12
19.18
C-5
17.53
43.04
0.31
3.19
17.34
C-4
15.12
40.67
0.3
3.29
14.92
4
MBCOjEngineering, LLC.
MOSS BLETSCH CRENEK OLLER
Table 2 - Summary of Peak Discharges Cont.)
IEA
CULVERT ID
CUMULATIVE
AREA
(ac)
TC
(minutes)
CUMULATIVE
C VALUE
INTENSITY
(in/hr)
CUMULATIVE
DISCHARGE
(cfs)
DITCH C
C-3
12.32
35
0.28
3.59
12.38
C-2
11.95
33.61
0.27
3.67
11.84
C-1
5.07
33
0.33
3.7
6.19
DITCH D
0-24
23.91
52.99
0.43
2.81
28.89
0-23
21.41
50.03
0.44
2.91
27.45
D-22
20.54
48.6
0.45
2.97
27.45
0-21
20.05
47.73
0.45
3
27.07
D-20
19.67
47.09
0.45
3.02
26.73
D-19
18.43
44.84
0.45
3.11
25.79
0-18
17.11
44.17
0.45
3.14
24.18
D-17
14.46
43.3
0.46
3.18
21.15
D-16
13.34
39.88
0.47
3.33
20.88
0-15
12.45
38.86
0.47
3.38
19.78
0-14
10.08
36.37
0.46
3.51
16.28
0-13
8.64
34.91
0.39
3.59
12.10
D-12
6.8
32.56
0.38
3.73
9.64
D-11
4.73
30.72
0.39
3.85
7.10
D-10
4.57
29.27
0.39
3.95
7.04
D-9
4.46
28.24
0.38
4.02
6.81
D-7
4.28
26.63
0.38
4.14
6.73
D-6
3.99
24.51
0.38
4.32
6.55
0-5
3.04
22.3
0.37
4.52
5.08
0-4
2.39
19.78
0.36
4.78
4.11
D-3
1.99
18.19
0.35
4.96
3.45
D-2
1.55
16.55
0.34
5.16
2.72
0-1
0.96
15
0.41
5.37
2.11
5
MBCO
Engineering, LLC.
MOSS I BLETSCH CRENEK OLLER
Table 3 - Summary of Driveway Culverts
3 -Year Storm Event
IEA
CULVERT
ID
STATION
CUMULATIVE
AREA
(ac)
CUMULATIVE
DISCHARGE
(cfs)
CULVERT
N -VALUE
CULVERT
SLOPE
(FT/FT)
CULVERT
QUANTITY
PIPE
DIAMETER
(FT)
CULVERT
CAPACITY
(CFS)
DITCH A
A-1
0+71.30
14.02
31.09
0.013
0.002
4
2
40.58
A-2
1+86.41
13.77
31.08
0.013
0.002
4
2
40.58
A-3
3+76.74
12.7
29.14
0.013
0.002
3
2
30.43
A-4
5+03.44
11.94
27.59
0.013
0.002
3
2
30.43
A-5
6+40.74
11.11
25.56
0.013
0.002
3
2
30.43
A-6
7+16.72
10.65
24.43
0.013
0.002
3
2
30.43
A-7
8+06.51
10.11
23.23
0.013
0.002
3
2
30.43
A-8
9+69.38
8.64
19.16
0.013
0.002
2
2
20.29
A-9
11+22.78
6.21
11.54
0.013
0.002
2
2
20.29
A-10
12+09.04
5.51
9.56
0.013
0.002
1
2
10.14
A-11
13+04.16
4.22
7.53
0.013
0.002
1
2
10.14
A-12
15+14.64
1.4
2.73
0.013
0.002
1
1.5
4.71
DITCH B
8-1
2+56.68
21.16
35.73
0.013
0.002
4
2
40.58
8-2
3+47.56
21.06
35.73
0.013
0.002
4
2
40.58
B-3
4+23.82
20.77
35.73
0.013
0.002
4
2
40.58
B-4
5+18.42
20.4
35.67
0.013
0.002
4
2
40.58
B-5
6+61.02
19.85
34.88
0.013
0.002
4
2
40.58
B-6
7+41.12
19.55
34.80
0.013
0.002
4
2
40.58
B-7
8+42.49
17.11
31.09
0.013
0.002
4
2
40.58
B-8
10+37.53
14.1
26.14
0.013
0.002
3
2
30.43
8-10
11+83.87
7.88
14.17
0.013
0.002
2
2
20.29
8-11
12+98.95
1.22
2.52
0.013
0.002
1
1.5
4.71
B-12
13+83.95
1.07
2.24
0.013
0.002
1
1.5
4.71
B-13
14+39.05
0.98
2.11
0.013
0.002
1
1.5
4.71
8-14
15+03.25
0.87
1.93
0.013
0.002
1
1.5
4.71
8-15
16+45.72
0.65
1.50
0.013
0.002
1
1.5
4.71
DITCH C
C-18
46+42.00
50.02
41.84
0.013
0.002
5
2
50.72
C-17
41+85.88
40.35
36.44
0.013
0.002
4
2
40.58
C-16
41+30.16
39.44
35.89
0.013
0.002
4
2
40.58
C-15
40+47.45
38.24
34.19
0.013
0.002
4
2
40.58
C-14
38+78.55
33.74
30.86
0.013
0.002
4
2
40.58
C-13
38+35.49
33.61
30.74
0.013
0.002
4
2
40.58
C-12
37+90.60
33.43
30.80
0.013
0.002
4
2
40.58
6
MBCO
Engineering, LLC.
MOSS 1 BLETSCH , CRENEK OLLER
Table 3 - Summary of Driveway Culverts (Cont.)
IEA
CULVERT
ID
STATION
CUMULATIVE
AREA
(ac)
CUMULATIVE
DISCHARGE
(cfs)
CULVERT
N -VALUE
CULVERT
SLOPE
(FT/FT)
CULVERT
QUANTITY
PIPE
DIAMETER
(FT)
CULVERT
CAPACITY
(CFS)
DITCH C
C-11
36+34.10
32.62
29.71
0.013
0.002
3
2
30.43
C-10
34+00.40
31.11
29.26
0.013
0.002
3
2
30.43
C-9
31+79.06
25.97
24.35
0.013
0.002
3
2
30.43
C-8
30+38.19
21.05
20.21
0.013
0.002
2
2
20.29
C-7
28+95.73
20.62
20.06
0.013
0.002
2
2
20.29
C-6
27+25.87
19.83
19.18
0.013
0.002
2
2
20.29
C-5
26+12.93
17.53
17.34
0.013
0.002
2
2
20.29
C-4
24+32.73
15.12
14.92
0.013
0.002
2
2
20.29
C-3
20+10.61
12.32
12.38
0.013
0.002
2
2
20.29
C-2
19+09.14
11.95
11.84
0.013
0.002
2
2
20.29
C-1
18+52.08
5.07
6.19
0.013
0.002
2
1.5
9.42
DITCH D
D-24
46+73.25
23.91
28.89
0.013
0.002
3
2
30.43
D-23
44+08.76
21.41
27.45
0.013
0.002
3
2
30.43
D-22
42+84.31
20.54
27.45
0.013
0.002
3
2
30.43
D-21
42+07.88
20.05
27.07
0.013
0.002
3
2
30.43
D-20
41+51.61
19.67
26.73
0.013
0.002
3
2
30.43
D-19
39+55.38
18.43
25.79
0.013
0.002
3
2
30.43
D-18
38+97.67
17.11
24.18
0.013
0.002
3
2
30.43
D-17
38+25.10
14.46
21.15
0.013
0.002
3
2
30.43
D-16
35+40.85
13.34
20.88
0.013
0.002
3
2
30.43
D-15
34+57.63
12.45
19.78
0.013
0.002
2
2
20.29
D-14
32+65.31
10.08
16.28
0.013
0.002
2
2
20.29
D-13
31+56.57
8.64
12.10
0.013
0.002
2
2
20.29
0-12
29+96.84
6.8
9.64
0.013
0.002
2
1.5
9.42
D-11
28+80.51
4.73
7.10
0.013
0.002
2
1.5
9.42
D-10
27+90.61
4.57
7.04
0.013
0.002
2
1.5
9.42
D-9
27+27.81
4.46
6.81
0.013
0.002
2
1.5
9.42
D-7
26+23.00
4.28
6.73
0.013
0.002
2
1.5
9.42
0-6
24+89.15
3.99
6.55
0.013
0.002
2
1.5
9.42
0-5
22+90.28
3.04
5.08
0.013
0.002
2
1.5
9.42
D-4
21+52.49
2.39
4.11
0.013
0.002
1
1.5
4.71
D-3
20+67.51
1.99
3.45
0.013
0.002
1
1.5
4.71
0-2
19+61.06
1.55
2.72
0.013
0.002
1
1.5
4.71
0-1
18+60.24
0.96
2.11
0.013
0.002
1
1.5 7 4.71
7
z
1 inch = 400 feet
LEGEND
I DRAINAGE BOUNDARY
FLOW DIRECTION
STREAM
IEA
ELEVATIONS
-54
so 8571
IR
47 7143
- 445714
41 4288
- 382857
- 35 1429
- 32
1225 MORT11 LOOP WEST, SUITE 32$
110987011. TX 77005
!32-166.3100
new ligaornomo“
WAGON TRAIL
DRAINAGE ANALYSIS
IEA No. 2026
AUGUST 2010
EXHIBIT 2
I
1
:1
•
Profile View of Fite Rd
StoGDn
b
9 rS r
A tet'—*i%?E.....� L -i.. J-. l.. 4.7- Y 1 _ �.L., 17-..4...4
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°
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C.ly of Peorlo.0. Te.os
ROAD
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0000 WATR00 CAI.10 EAST
0100E
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9 3{
I I-
rn
:'iS
Profile View of Wagon Trait Rood (East Di;c'.)
Station
—_� I _ ,
rr
(W esL Citcf
r
"'^
- - - -
' - - -
,..:Y of ?CGrono. Te os
AGON RAI
S REGnE R
ROOM BMOC
ROOM B4ROET ST TO !iE RD
`.1r�`
1
a we wr w« »+s wA »..• wr wr w.r rw r.a a.a as r.a ... A.. .... ... ,•'m —. ... ... ,..,. ... ... �.. ,... �.... ...
.'"'•
RESPONSIVE RESULTS -ORIENTED TRUST -BUILDERS ACCOUNTABLE
Exhibit E
November 20, 2015
City of Pearland
3519 Liberty Drive
Pearland, Texas 77581
Tel: 281.625.1641
pearlandtx.gov
Mona and Sergio Chavaria
A & A Cleaning Services
2810 Wagon Trail Road
Pearland, TX 77584
Dear Mr. & Mrs. Chavaria:
Beginning the week of November 23, 2015, the City of Pearland will commence a ditch
and culvert maintenance project along Wagon Trail Road and Fite Road with
preliminary preparation currently underway. Ditches will be regraded and culverts
replaced along the east and west sides of Wagon Trail Road between Bardet Road and
Fite Road as well as the north side of Fite Road from Wagon Trail Road to the Corrigan
Diversion ditch. In addition to the ditch/culvert work, a damaged culvert at the
intersection of Wagon Trail Road and Fite Road will be replaced requiring periodic road
closures and detours. Several of the culverts will be up-sized to allow flow for a 3 -year
storm design which is the City's standard on residential streets. Weather permitting,
this work should be completed by December 318t.
This work should allow for improved conveyance of storm water in the immediate area
around Wagon Trail Road and Fite Road. The maintenance work and basic
improvements that we have and are undertaking with our operations staff is of scope
within the existing public right-of-way to improve drainage without causing unintended
negative consequences. However, what we are going to undertake this year is not a
solution to the flooding that you have been experiencing on your property further to the
north. Properties with localized water during intense rainfalls may still have episodes,
particularly for properties that have additional impervious surfaces or grades below
roadways. As we have shared, you can continue to review your options for stormwater
management on your property with whatever professional design assistance you deem
appropriate.
The City is in the process of preparing a City-wide Master Drainage Plan. As a part of
this plan, your neighborhood will be studied and potential drainage solutions will be
identified. Staff will utilize this information to develop and prioritize future Capital
Improvement projects.
RESPONSIVE RESULTS -ORIENTED TRUST -BUILDERS ACCOUNTABLE -
If you have any questions, please contact me at 281-652-1641 or spolka@nearlandtx.eov.
Sincerely,
Susan Polka, P.E.
Director of Engineering
Cc: Trent Epperson, Asst. City Manager
Mike Leech, Asst. Public Works Director
Andrea Broughton, Brazoria County Drainage District #4
RESPONSIVE RESULTS -ORIENTED TRUST -BUILDERS ACCOUNTABLE
November 20, 2015
City of Pearland
3519 Liberty Drive
Pearland, Texas 77581
Tel: 281.625.1641
pearlandtx.gov
Sandy and Roland Cavazos
A -Better Plumbing
5828 W. Broadway Street
Pearland, TX 77581
Dear Mr. & Mrs. Cavazos:
Beginning the week of November 23, 2015, the City of Pearland will commence a ditch
and culvert maintenance project along Wagon Trail Road and Fite Road with
preliminary preparation currently underway. Ditches will be regraded and culverts
replaced along the east and west sides of Wagon Trail Road between Bardet Road and
Fite Road as well as the north side of Fite Road from Wagon Trail Road to the Corrigan
Diversion ditch. In addition to the ditch/culvert work, a damaged culvert at the
intersection of Wagon Trail Road and Fite Road will be replaced requiring periodic road
closures and detours. Several of the culverts will be up-sized to allow flow for a 3 -year
storm design which is the City's standard for residential streets. Weather permitting,
this work should be completed by December 31st.
This work should allow for improved conveyance of storm water in the immediate area
around Wagon Trail Road and Fite Road. The maintenance work and basic
improvements that we have and are undertaking with our operations staff is of scope
within the existing public right-of-way to improve drainage without causing unintended
negative consequences. However, what we are going to undertake this year is not a
solution to the flooding that you have been experiencing on your property further to the
north. Properties with localized water during intense rainfalls may still have episodes,
particularly for properties that have additional impervious surfaces or grades below
roadways. As we have shared, you can continue to review your options for stormwater
management on your property with whatever professional design assistance you deem
appropriate.
The City is in the process of preparing a City-wide Master Drainage Plan. As a part of
this plan, your neighborhood will be studied and potential drainage solutions will be
identified. Staff will utilize this information to develop and prioritize future Capital
Improvement projects.
RESPONSIVE RESULTS -ORIENTED TRUST -BUILDERS ACCOUN-!ABLE
If you have any questions, please contact me at 281-652-1641 or spolka@pearlandtx.gov.
Sincerely,
Susan Polka, P.E.
Director of Engineering
Cc: Trent Epperson, Asst. City Manager
Mike Leech, Asst. Public Works Director
Andrea Broughton, Brazoria County Drainage District #4