HomeMy WebLinkAboutOrd 971-2022 Drainage Utility System and Service AreaCITY OF ANNA, TEXAS
ORDINANCE NO. q 9 I -gDav2
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF ANNA, TEXAS, AMENDING
THE ANNA CITY CODE OF ORDINANCES TO ADD A NEW ARTICLE 12.09 TO CHAPTER
12 (UTILITIES), SAID NEW ARTICLE ESTABLISHING THE CITY OF ANNA' S
DRAINAGE UTILITY SYSTEM AND ITS SERVICE AREA; DEDICATING CITY ASSETS
TO THE DRAINAGE UTILITY SYSTEM, AND ADOPTING RELATED REGULATIONS;
PROVIDING FOR EXEMPTIONS; PROVIDING FOR SEVERABILITY; PROVIDING
FOR REPEALER AND AN EFFECTIVE DATE.
WHEREAS, the City of Anna City Council (the "City Council") finds that to protect the public health
and safety from loss of life and property caused by surface water overflows, surface water stagnation,
and pollution arising from nonpoint source runoff within the city; and
WHEREAS, the City Council finds that funding for improvement of the existing drainage system and
construction of future drainage projects is best funded by users of the drainage system on a prorated
basis; and
WHEREAS, the City Council desires to establish a municipal drainage utility system and this ordinance
is adopted for that purpose pursuant to the Texas Local Government Code, Subchapter C, Sections
552.041. et seq., as amended; and
WHEREAS, the City Council finds that pursuant to the Local Government Code, Section 552.045:
(a) it will establish a schedule of drainage charges against all real property in the service area subject
to charges as permitted by Subchapter C, Chapter 552, Texas Local Government Code, subject to
any exemptions as required or permitted by Subchapter C as set forth herein;
(b) it will provide drainage for all real property in the service area on payment of drainage charges,
except real property exempted in accordance with Subchapter C;
(c) it will offer drainage service on nondiscriminatory, reasonable, and equitable terms; and
(d) notice as required by Subchapter C has been provided and a public hearing has been held; and
WHEREAS, the City Council finds that certain persons and entities shall be exempt from the rules,
regulations, and charges imposed by the new 12.09 (Drainage), of The Anna City Code of Ordinances;
NOW, THEREFORE, BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF ANNA,
TEXAS:
SECTION 1. The recitals set forth above are incorporated herein as if set forth in full and The Anna
City Code of Ordinances Chapter 12 (Utilities) is amended to add Article 12.09 (Drainage), to read as
follows:
CITY OF ANNA, TEXAS ORIDINANCE NO. Page 1 of 7
ARTICLE 12.09. DRAINAGE
See.12.09.001 Definitions.
Benefitted property. An improved lot or tract to which drainage service is made available under this
article.
City. The City of Anna, Texas.
City council. The city's governing body.
Cost of service. As applied to the drainage utility system service to any benefitted property:
(a) the prorated cost of the acquisition, whether by eminent domain or otherwise, of land, rights -of -
way, options to purchase land, easements, and interests in land relating to structures, equipment,
and facilities used in draining the benefitted property;
(b) the prorated cost of the acquisition, construction, repair, and maintenance of structures,
equipment, and facilities used in draining the benefitted property;
(c) the prorated cost of architectural, engineering, legal, and related services, plans and
specifications, studies, surveys, estimates of cost and of revenue, and all other expenses
necessary or incident to planning, providing, or determining the feasibility and practicability of
structures, equipment, and facilities used in draining the benefitted property;
(d) the prorated cost of all machinery, equipment, furniture, and facilities necessary or incident to the
provision and operation of draining the benefitted property;
(e) the prorated cost of funding and financing charges and interest arising from construction projects
and the start-up cost of a drainage facility used in draining the benefitted property;
(f) the prorated cost of debt service and reserve requirements of structures, equipment, and facilities
provided by revenue bonds or other drainage revenue -pledge securities or obligations issued by
the city; and
(g) the administrative costs of a drainage utility system.
Drainage. Bridges, catch basins, channels, conduits, creeks, culverts, detention ponds, ditches, draws,
flumes, pipes, pumps, sloughs, treatment works, and appurtenances to those items, whether natural or
artificial, or using force or gravity, that are used to draw off surface water from land, carry the water
away, collect, store, or treat the water, or divert the water into natural or artificial watercourses.
Drainage utility. The drainage utility established under this article in accordance with Subchapter C.
Drainage utility system. The drainage system owned or controlled in whole or in part by the city and
dedicated to the service of benefitted property, including provisions for additions to the system.
CITY OF ANNA, TEXAS ORIDINANCE NO. Page 2 of 7
Equivalent Residential Unit (ERU). An area of impervious coverage on an improved lot or tract that is
generally equal to the average impervious area on a single family property in the City limits, calculated
as 3,600 square feet.
User. The person or entity who owns or occupies a benefitted property.
Impervious Cover. Impervious area for the purpose of the SDUS charge, defined below, means any
surface or subsurface of benefitted property including, but not be limited to, roads, parking areas,
buildings, roofs, pools, patios, sheds, driveways, private sidewalks, compacted subgrades, compacted
gravel used for vehicular traffic and/or parking, and other impermeable construction that does not
readily absorb water and has the effect of increasing water runoff flow rate or runoff volume that drains
to the drainage utility system.
Improved lot or tract. A lot or tract that has a structure or other improvement on it that causes an
impervious coverage of the soil under the structure or improvement.
Surface water drainage utility system (SD US) charge means the total monthly drainage charge for a
benefitted property as calculated under this article and the schedule of charges adopted by the city
council, as may be modified from time to time.
"oily sufficient and privately owned drainage system. Land owned and operated by a person other than
a municipal drainage utility system the drainage of which does not discharge into a creek, river, slough,
culvert, or other channel that is part of the drainage utility system.
Sec.12.09.002 Establishment of drainage utility.
The provisions of Subchapter C, Chapter 552, Texas Local Government Code ("Subchapter C"), are
hereby adopted to create a drainage utility for the city. Accordingly, drainage of the city is hereby
declared to be a public utility. The city incorporates into the drainage utility system all existing
property, facilities, materials, and supplies constituting the city's drainage utility system on the
effective date of this article. All future acquisitions by the city of real or personal property used in
the city's drainage utility system shall be maintained as a part of the drainage utility.
Sec. 12.09.003 Service area.
The service area for the drainage utility shall include all real property within the city limits of the
City of Anna as now existing and which may be annexed hereafter from time to time.
Sec. 12.09.004 Calculation of drainage charges.
(a) The city council finds that:
(1) impervious cover increases water runoff and associated pollutants: and
CITY OF ANNA, TEXAS ORIDINANCE NO. Page 3 of 7
(2) rates charged shall be based on a benefitted property's impact on the drainage utility
system; and
(3) it is fair and equitable to calculate the impact and assess the drainage charge to each
benefitted property based on impervious cover, subject to the limitation set forth below
for single family residential properties.
(b) The city council hereby imposes a drainage charge to be paid by users of benefitted property
to cover the cost of service of the drainage utility system. Said drainage charge shall be set forth in
a schedule of charges to be adopted by the city council and calculated as follows:
(1) Single family residential properties shall be measured as one ERU per month regardless
of actual amount of impervious cover on such properties;
(2) except with respect to the limitation for single family residential properties set forth in
subsection (1), above, all non-exempt benefitted properties shall be measured for ERU in
one/tenth increments with no maximum and for such non-exempt properties there shall be a
minimum of one ERU regardless of actual amount of impervious cover on such properties;
and
(3) Each benefitted property shall be assessed a monthly SDUS fee to be established by the city
council in a schedule of charges. The schedule of charges shall be included in Appendix A
Schedule of Fees.
(c) The city council may adjust the values, rates, and fees at any time based upon the
recommendation of the city manager that the cost of service for the drainage utility warrants an
adjustment in rates.
(d) The rates to be imposed shall be collected through the city's bill for public utilities in accordance
and be set forth therein as a separate charge.
Sec. 12.09.006 Segregation of income.
The income of the drainage utility system shall be segregated and completely identifiable in city
accounts. If drainage charges are solely for the cost of service, the city may transfer the charges in whole
or in part to the city's general fund, except for any part collected outside municipal boundaries and
except for any part pledged to retire any outstanding indebtedness or obligation incurred, or as a reserve
for future construction, repair, or maintenance of the drainage utility system. If the city council has
levied, in the drainage charge, an amount in contribution to the funding of future system improvements,
including replacement, new construction, or extension, that amount is not transferable to the general
fund.
Sec. 12.09.007 Exemptions; fee credits.
(a) The following shall be exempt from the provisions of this article:
CITY OF ANNA, TEXAS ORIDINANCE NO. Page 4 of 7
(1) property with proper construction and maintenance of a wholly sufficient and privately
owned drainage system;
(2) property held and maintained in its natural state until such time that the property is
developed and all of the public infrastructure constructed has been accepted by the city
for maintenance;
(3) a subdivided lot until a structure has been built on the lot and a certificate of
occupancy has been issued by the city;
(4) property owned by the United States, the State of Texas, or Collin County;
(5) property owned by Anna Independent School District and private K-12 education
providers;
(6) property owned by public or private institutions of higher education; and
(7) property owned by a religious organization that is exempt from taxation pursuant to Section
11.20, Tax Code.
(b) A property owner may petition the city to reduce the drainage utility fee for an individual
property to account for on -site stormwater management controls that reduce the property's impact
to the drainage utility system. The petition shall be evaluated and the fee adjustment decision
determined by the city engineer or the engineer's designated representative. The evaluation and
determination performed by the city engineer shall be based on nondiscriminatory, reasonable and
equitable terms in accordance with the applicable law and this section.
Sec. 12.09.008 No effect on land owner obligations under city ordinances; no waiver of
immunity; other laws and obligations.
(a) The establishment of the drainage utility by the city does not relieve users, private land
owners, developers, other individuals or entities from responsibility for providing drainage
improvements in connection with land development pursuant to the other ordinances of the city or
laws of the State of Texas that relate to flooding, drainage, drainage management, or drainage
improvements.
(b) The establishment of the drainage utility does not imply or warrant that a benefitted
property will be free from flooding, pollution, or stream erosion. The city makes no representation
that all drainage problems will be remedied. This ordinance does not create additional duties on the
part of the city or create new liability or remedies for any flooding, stream erosion, deterioration of
water quality, or other damages. Nothing in this ordinance shall be deemed to waive the city's
immunity under law or reduce the need or necessity for flood insurance.
(c) This article is intended to be read in harmony with all other provisions of this Code. To the
extent this article conflicts with any other provision in this code, the provisions shall be harmonized
CITY OF ANNA, TEXAS ORIDINANCE NO. Page 5 of 7
when possible, however, this article shall control and supersede any other conflicting provision
regarding the drainage utility system.
(d) A wholly sufficient and privately owned drainage system must have volume to capture
runoff for storms of magnitude up to and included in the one -percent annual chance (100-year)
storm event, 24-hour duration. Captured runoff must be removed from the retention system of a
wholly sufficient and privately owned drainage system within 72 hours of the rainfall event without
discharging into the drainage utility system. Owner of the wholly sufficient and privately owned
drainage system must provide evidence to the city to show the facility meets the above
requirements. Failure to comply with this provision shall result in a wholly sufficient and privately
owned drainage system being deemed to be a benefitted property and subject to the SDUS charge
and other provisions of this article.
Sec. 12.09.009 Delinquencies.
Any charge due hereunder which is not paid when due may be recovered in an action at law by the city.
In addition to any other remedies or penalties provided in Subchapter C or other law, failure of a user
within the service area to pay the charges promptly when due shall subject such user to discontinuance
of any utility services provided by the city. City employees of the utility drainage system shall have
access, at all reasonable times, to any benefitted properties served by the drainage utility for inspection
or repair or for the enforcement of the provisions of this article; provided, however that this section does
not authorize entry, access or searches where a search warrant is required.
Section 12.09.010 Appeals.
(a) Billing and payment disputes for administrative issues shall be subject to appeals procedures
used by the city for other utility billing disputes.
(b) Appeals for the following reasons shall be directed to the public works director or his designee
for evaluation and determination:
(1) exempt property has been assessed a charge under this article;
(2) a charge under this article for an individual property is based on an incorrect determination of
the property's contribution to the drainage utility system, as established in accordance with the
schedule of charges referenced in Sec. 12.09.004(b)(3);
(3) a charge under this article for an individual property is assessed on more than one utility
account;
(4) a charge under this article is assessed to individual property outside the service area; or
(5) a benefitted property has boundaries or dimensions that deviate from the city's determination
of the boundaries or dimensions for such benefitted properly.
CITY OF ANNA, TEXAS ORIDINANCE NO. Page 6 of 7
(c) The public works director or his designee shall render a written decision on such appeals within
thirty (30) days after receiving a written notice of appeal from the user.
(d) Any user who disagrees with the decision of the public works director or his designee may
appeal to the city manager. The city manager shall render a written decision on such appeals
within thirty (30) days after receiving a written notice of appeal from the user. The city
manager's decision is final. If the city manager does not render a decision within thirty (30) days
of an appeal, it shall be deemed to have sustained the decision of the public works director.
SECTION 2. Savings, Severability and Repealing Clauses.
All ordinances of the City in conflict with the provisions of this ordinance are repealed to the extent of
that conflict. If any provision of this ordinance shall be held to be invalid or unconstitutional, the remainder
of such ordinance shall continue in full force and effect the same as if such invalid or unconstitutional
provision had never been a part hereof. The City declares that it would have passed this ordinance, and
each section, subsection, sentence, clause, or phrase thereof irrespective of the fact that anyone or more
sections, subsections, sentences, clauses, and phrases be declared unconstitutional or invalid.
SECTION 3. Publication of the Caption Hereof and Effective Date.
This ordinance shall be in full force and effective from and after its passage and upon the posting and/or
publication, if required by law, of its caption and the City Secretary is hereby directed to implement such
posting and/or publication.
PASSED by the City Council of the City of Anna, Texas, this &ikay of , 2022.
ATTESTED: APPROVED:
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CITY OF ANNA, TEXAS ORIDINANCE NO. Page 7 of 7
MUNICIPAL DRAINAGE UTILITY
2021 RATE ANALYSIS
Prepared For
THE CITY OF
manna
Prepared By
BIRKHOFF, HENDRICKS & CARTER, L.L.P.
PROFESSIONAL ENGINEERS
DALLAS, TEXAS
TBPELS FIRM NO. 526
October 2021
A. Introduction
B. Service Area
C. Calculation Method
D.
E.
F.
G.
H.
I.
J.
CITY OF ANNA, TEXAS
MUNICIPAL DRAINAGE UTILITY
(STORMWATER SYSTEM)
2021 RATE ANALYSIS
TABLE OF CONTENTS
Page No.
...... 1
......................................... 1
......................................... 2
Rate Categories (Land Uses)..................................................................................................
2
• Figure 1 — Rate Categories Map....................................................................................
4
Land Uses & Charge Distribution...........................................................................................
5
• Table 1 — Rate Categories Summary & Budget Allocation
Stormwater System Capital Improvement Plan......................................................................
6
• Table 2 — Summary of 10-year CIP Expenditures........................................................
7
• Figure 2 — Stormwater System CIP Map......................................................................
8
Capital improvements Plan Annualized Debt Service..............................................................
9
• Table 3 — Annualized Capital Improvement Project Debt Service
Operation & Maintenance Annualized Expenditures...........................................................
10
• Table 4 — Operation & Maintenance Budget..............................................................
11
Storm Water Utility Rate Options........................................................................................
12
1) 10-year Level Approach
• Table 5 — Stormwater Utility Rate (O&M Budget Only) .............................................
12
• Table 6 — Stormwater Utility Rate (CIP Only).............................................................
12
• Table 7 — Stormwater Utility Rate (Combined O&M and CIP)..................................
12
2) 10-year Annual Analysis (Supplemental Approach).....................................................
13
• Table IA — Cale. of Runoff Contribution by Property Category (Annual Estimate ...
14
• Table 5A — Stormwater Utility Rate (O&M Budget Only) .........................................
14
• Table 6A — Stormwater Utility Rate (CIP Only) ........................................................
15
• Table 7A— Stormwater Utility Rate (Combined O&M and CIP) ...............................
15
Non -Residential Stormwater Detention System Fee Credit .................................................
16
� 1r:' '•.itJJ
♦ GARY C. HENDRICKS i
�......... ....................:...�
65226
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jAcluical\anna\2020 drainage utility analysis\02_index.doc
Birkhoff, Hendricks & Carter, L.L.P.
CITY OF ANNA
MUNICIPAL DRAINAGE UTILITY
2021 RATE ANALYSIS
A. INTRODUCTION
A "Drainage Charge" is a fee that is imposed by a municipality and used to finance a municipal
drainage utility system. The drainage charge is to be imposed to all benefitted properties in the
service area of the stormwater drainage system, excluding properties such as parks, other public -
use facilities or undeveloped land. The drainage charge shall be levied on nondiscriminatory,
equitable and reasonable terms, regardless the value of a property. The drainage charge rates
are based on the estimated stormwater runoff rate (flow contribution) from each benefitted
property and on the budgetary requirements for provision, operation and maintenance of the
system.
This analysis calculates the drainage charge rates that are required to be obtained to meet the
financial requirements of the system, including the cost of operation and maintenance (O&M)
and the cost of the capital improvement plan (CIP) projects. That total cost is distributed among
the benefitted properties, proportionally, based on the land uses and estimated runoff rates from
the properties. The rates calculated are recommended monthly fees.
The calculation of the rates does not consider capacities of existing facilities or the geographical
location of each benefitted property in relationship to the proposed capital improvement
projects. Prior investments to the stormwater system are not included in the rate calculation.
Regulation set forth by Title 13, Subtitle A, Chapter 552 of the Local Government Code
provides the framework and requirements for the Drainage Charge and Rates calculation.
B. SERVICE AREA
The 7,777-acre City of Anna City Limits was the Service Area for this analysis.
jAclericahanna12020 drainage utility analysis103_report.docx - I -
Birkhoff, Hendricks & Carter, L.L.P.
C. CALCULATION METHOD
The approach taken to classify land uses was related to the estimation of runoff rates for a per -
acre assessment. The Rational Method, used for estimation of stormwater runoff rates, assigns
coefficient values to various land use types which correspond to the portion of rainfall expected
to runoff from a unit of land area, based on impervious cover.
Variable coefficient `C' of the Rational Method Equation (Q = CiA) is the factor related to an
area's impervious coverage (likewise, related to the area's ability to retain rainfall). Coefficient
`C' is multiplied by the watershed area `A' and by the rainfall intensity `i' to calculate a runoff
flow rate `Q'. For this calculation, C*A was used to define the runoff characteristics for the
property types in the service area. C*A can be applied to storms of various intensities, and
therefore, the rainfall intensity factor, `i', was not used.
The eligible and benefitted properties in the service area were distinguished into impervious -
coverage categories. Runoff coefficients, `C' -values, were assigned to each category, per the
City of Anna Storm Drainage Design Manual. An analysis of the City's parcel areas was
conducted to determine each category's flow contribution percentage to the total runoff. Those
percentages of the total runoff were applied to the required average monthly budget to allocate
the required fees and to determine the rates.
D. RATE CATEGORIES (LAND USE
Drainage charge rates were calculated for land use Categories 1 through 3:
1. Residential
2. Non -Residential
3. Exempt Lands
a. Collin County
b. School District
c. Public/ Semi -Public &Parks
d. Undeveloped (Natural State) or Unoccupied
e. Religious or Cemetery (optional exemption)
It was assumed that the tracts of land within each category have similar runoff characteristics.
Non-residential tracts of land typically have more impervious coverage than residential tracts
due to larger concrete parking lots and buildings, while residential tracts tend to have larger
portions of grassed area which detain and percolate stormwater.
The Land Use Categories are defined by measurable qualities, where applicable, for the
assignment of fee classification for each benefitted property.
jAclericahanna12020 drainage utility analysis103_regort.docx - 2 -
Birkhoff, Hendricks & Carter, L.L.P.
• Residential Properties— Properties used for residential dwelling.
• Non -Residential Properties — Tracts of land which are not used for residential dwelling
and are developed such that the natural state of the property is altered may be classified
as a non-residential property, unless the property was determined to be exempt per local
government code (Section 552.053)
• Public Properties (Exempt Land) —Per the Local Government Code, tracts of land owned by
Collin County or by a school district are exempt from drainage charges, and residential
dwellings associated with a municipal housing authority are also exempt. Undeveloped
properties held and maintained in the natural state are exempt, and subdivided lots or tracts that
have not been issued a certificate of occupancy are exempt. Additionally, properties which
utilize a wholly sufficient and privately owned drainage system are exempt. The City may also
grant exemption from the drainage charge if a property is owned by a religious organization or
used as a cemetery. A map showing the geographical distribution of the Rate Categories (Land
Uses) is provided as Figure 1.
jAclericahanna12020 drainage utility analysis103 report.docx - 3 -
STORMWATER UTILITY RATE ANALYSIS
THE CITY OF LAND USE RATE CATEGORIES
BIRKIIO TB? IIENDRICKS & CARTER L.L.P. Atttla
PROFESSIONAL ENGINEERS FIGURE 1
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Birkhoff, Hendricks & Carter, L.L.P.
E. LAND USES & CHARGE DISTRIBUTION
The Texas Administrative code allows for the drainage charge rates to be established on the
basis of impervious cover as it relates to land use. The mechanism for distribution of the
required monthly budget (being the same as the required revenue) to the properties is by a ratio
of the runoff rate calculated for the parcel in question to the total runoff rate calculated for the
entire service area.
A uniform drainage charge rate is recommended for all properties classified as Single Family
Residential and High Density Residential, due to relative uniformity in size and in impervious
coverage, and therefore the calculation for runoff uses the average property size for those
categories. Non -Residential properties, however, vary more widely by land area, and the rates
calculated for those properties are based on the land area of the individual properties
themselves.
Table 1 summarizes the current and 10-year projected developed parcel counts and areas for
both Residential and Non -Residential lots within the service area. The table includes the 10-
Year Level Average for the developed parcels and acres for each category. The table also
calculates fee allocation percentages using runoff coefficients, `C'-values, with the parcel counts
and areas.
Takla 4 - r`nlr Infirm of Rnnnff rnnfrihnfinn by Prnnarfv rafannry
Rate Category
2021
2031
10-Year Level Average
Runoff(d)
Coefficient
'C'
Weighted
Value
T-A'
Porportional
Share Based on
C*A
eveloped ParcelE
Developed Acres(a)
Developed Parcelslbl
Developed Acreslbl
Developed Parcels
Developed Acre
Residential:
6,250
3,424
10,667
5,844
8,459
4,634
0.50
2,317
88.01%
Non -Residential:
N/A
260
N/A
445
N/A
353
0.90
317
12.0%
Public:
N/A
662
N/A
661
N/A
662
0
0
0%
Total:
1 6,250
3,684
10,667
6,289
8,459
4,987
2,634
10006
(a) Developed lots ONLY
(b) Source: 2018City of Anna & Wastewater Impact Fee update landuse assumptions
(c) Direct Annual Average Growth per 2014 Land use assumptions: Source 2014 City of Anna & Wastewater Impact fee,Appendix A
(d) Runoff Coefficient 'C'represents impervious coverage of development on a property.
Source of 'C'-values : City of Plano Storm Drainage Design Manual
In Table 1, The `Proportional Share Based on C*A' column provides the percentages of the
budget that are to be obtained from parcels of each respective category.
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Birkhoff, Hendricks & Carter, L.L.P.
F. STORMWATER SYSTEM CAPITAL IMPROVEMENT PLAN
The City has developed a capital improvement plan for the stormwater utility system. The list
of proposed projects has been refined through discussion over the past several years. Six (6)
projects are expected to be completed over the next 10-years, or so. The projects were
distinguished as the following types:
• Bridge Projects —Nine (9) projects are proposed to construct a bridge over a creek. One
bridge is located on the west side of the City on the future extension of Creekview Drive.
This bridge would be constructed at the same time of the future extension of Creekview
Drive. The second bridge is located northeast of the City on F.M. 2862 (also known as
Houston Street). This second bridge would expand the existing bridge when proposed
expansion of F.M. 2862 is being constructed. Other seven bridges located across the City
would also be constructed.
• Culvert Projects — Four (4) Culverts are proposed for replacement, all of which are in
northwestern Anna. One of the proposed culverts cross under C.R. 369, two under C.R.
370, and one crosses under Hackberry Drive. Each of these projects include trench cuts
across the roadway for the installations. In addition to Roadway trench repair, the
projects may include construction of concrete headwalls and metal beam guard rail
fencing for safety. Minor upstream and downstream clearing, grading, and soil
stabilization activities are included in the culvert replacement projects, as warranted.
Table 2 summarizes the opinion of project cost for the sixteen (16) projects in the Capital
Improvement Plan. The projects are shown by Figure 2, the Capital Improvement Plan map.
The estimated budget and total required principal for the Capital Improvement Plan
improvements is $42,925,000.
jAclerical\anna\2020 drainage utility analysis\03_report.doex - 6 -
Birkhoff, Hendricks & Carter, L.L.P.
Table 2- Summary of 10-Year Capital Improvement Plan Expenditures
Project
LD,
Stormwater Drainage System
Proposed Improvement
pipe
Diameter
Length (ft)
Estimated
Construction Cost
Contingencies &
Esc.
Professional
Services
Ntaterial Testing
Inspection Fee
Total
Capital Cost
EFT-1
Storm Water Master Plan, East Fork Trinity, Crossing EFT-1
Bridge
245
3,008,235
601,647
451,235
75,206
75,206
4,212,000
TC-1
Storm Water Master Plan, Throckmorton Creek, Crossing TC-1
4 - 9'x8'
480
858,740
171,748
128,811
21,469
21,469
1,203,000
TC-2
Storm Water Master Plan, Throckmorton Creek, Crossing TC-2
84"
480
580,830
116,166
87,125
14,521
14,521
814,000
TC-3
Storm Water Master Plan, Throckmorton Creek, Crossing TC-3
4 - 9'x8'
480
857,245
171,449
128,587
21,431
21,431
1,201,000
TC-4
Storm Water Master Plan, Throckmorton Creek, Crossing TC-4
Bridge
95
3,007,785
601,557
451,168
75,195
75,195
4,211,000
TC-5
Storm Water Master Plan, Throckmorton Creek, Crossing TC-5
Bridge
85
3,007,755
601,551
451,163
75,194
75,194
4,211,000
TC-6
Storm Water Master Plan, Throckmorton Creek, Crossing TC-6
Bridge
115
3,007,673
601,535
451,151
75,192
75,192
4,211,000
5C-1
Storm Wate r Master Plan, Slayte r Cree k, Crossi ng SC-1
4-10'x8'
320
681,940
136,388
102,291
17,049
17,049
955,000
SC-2
Storm Wate r Master Plan, Slayter Cree k, Crossing SC-2
Bridge
75
3,007,725
601,545
451,159
75,193
75,193
4,211,000
SC-3
Storm Water Master Plan, Slayter Creek, Crossing SC-3
Bridge
250
3,008,250
601,650
451,238
75,206
75,206
4,212,000
SC-4
Storm Water Master Plan, Slayter Creek, Crossing SC-4
Bridge
1 55
3,007,665
601,533
451,150
75,192
75,192
4,211,000
WSGC-3
Storm Water Master Plan, West Sister Grove Creek, Crossing WSGC-3
TXDOT
0
0
0
0
0
0
0
WSGC-4
Storm Water Master Plan, West Sister Grove Creek, Crossing WSGC-4
4 - 910'
320
607,200
121,440
91,080
15,180
15,180
851,000
SGC-4
Storm Water Master Plan, Sister Grove Creek, Crossing SGC-4
Bridge
65
3,007,695
601,539
451,154
75,192
75,192
4,211,000
SGC-15
Storm Water Master Plan, SisterGrove Creek, Crossing SGC-15
Bridge
55
3,007,583
601,517
451,137
75,190
75,190
4,211,000
SGC-16
Storm Water Master Plan, SisterGrove Creek, Crossing SGC-16
I TOOT
1 0
0
1 0
0
0
0
1 0
Total:
I
530,656.320
56.131.264
I S4.598m
5766m
5766.408
I 542.925A00
jAclerical\ama\2020 drainage utility analysis\03_repoMdocx - 7 -
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Birkhoff' Hendriehs & Canter, L.L.P.
G. CAPITAL IMPROVEMENT PLAN ANNULIZED DEBT SERVICE
To pay for the Capital Improvement Plan projects, this analysis assumes the city to issue bonds
with a maximum value of $5 million dollars per issuance, with an issuance cost of 1.5%, an
interest rate of 4%, and a term of 20 years per issuance. Table 3 below calculates the average
Total Annual and Monthly Debt Service during the I0-year term of this evaluation.
Table 3 Annulized Captial Improvement Project Debt Service
Year
Issue 1(1)
Issue 24)
Issue 3(�)
Total Annual
Debt Service
Monthly Debt
Service
Amount
$5,000,000
$5,000,000
$5,000,000
2022
$373,427
$ -
$ -
$373,427.38
$31,118.95
2023
$373,427
$ -
$ -
$373,427.38
$31,118.95
2024
$373,427
$ -
$ -
$373,427.38
$31,118.95
2025
$373,427
$ -
$ -
$373,427.38
$31,118.95
2026
$373,427
$373,427
$ -
$746,854.77
$62,237.90
2027
$373,427
$373,427
$ -
$746,854.77
$62,237.90
2028
$373,427
$373,427
$ -
$746,854.77
$62,237.90
2029
$373,427
$373,427
$ -
$746,854.77
$62,237.90
2030
$373,427
$373,427
$373,427
$1,120,282.15
$93,356.85
2031
$373,427
$373,427
$373,427
$1,120,282.15
$93,356.85
Average:
$672,169.29
$56,014.11
(1) Note: Financing Terms
Issuance Cost: 1.5%
Term (Years) 20
Rate: 4%
jAc lei ical\anna\2020 drainage utility analysis\03_report.do- - 9 -
Birkhoff, Hendricks & Carter, L.L.P.
H. OPERATION & MAINTENANCE ANNUALIZED EXPENDITURES
The Estimated 2021 City of Anna Budget for the operation and maintenance (O&M) of the
Stormwater System is $103,105. Because there is not currently a sperate storm water utility
account, this amount represents ten percent (10%) of the City's Street Budget. The revenue is
used for general maintenance items such as mowing of channels, inspections and debris
removal. It is also used for administrative, planning and regulatory -compliance costs for
operation of the system.
City staff anticipates future expenditures which will increase the required O&M budget,
including personnel expansion, equipment purchases and Municipal Separate Storm Sewer
System (MS4) permitting. In the future, the required O&M budget will have a 10-Year
annualized average of approximately $289,070 per year. It is also anticipated that within the rate
study period, the city will be required to service a general permit for storm water discharge into
the waters of the U.S. As shown in Table 3 below, beginning in the year 2025 the operation and
maintenance budget includes a $75,000 fund for the municipal separate storm sewer system
(MS4) annual permit requirements and will grow with a 1.7% CPI rate.
Currently the budget has limited resources for proper and consistent stormwater maintenance.
Therefore, a new `Enhanced Storm water Maintenance' program has been created with an
initial amount of $175,000. This program will allow for the city to regularly maintain
stormwater utilities and equipment as the city grows.
Table 4 calculates the average annual budget required to operate and maintain the stormwater
system over the next ten years. The average annual O&M budget anticipated for the next 10-
years is $524,514. This is the O&M 10-year level amount utilized for this study.
The O&M expenses are to be recovered monthly through the drainage charge.
j:\clerical\anna\2020 drainage utility analysis\03_report.docx - 1 0 -
Birkhoff, Hendricks & Carter, L.L.P.
TABLE 4- Operation & Maintenance Budget
Year
Inflation
(CPI)
Rate (%)
Annual (A)
O&M Budget
Projection
Ehlianced Strom
Water Maintennace
Program
AIS4 Permit
Expenses
Capital
(Equipment)
Expenditure
Total Annual
Ammount ($) (d)
2021
1.7%
103 105
170 000
$0
$273,105
20221bi
1.7%
$284,857
$172,890
$0
$66,000
$457,747
2023
1.7%
$289,700
$175,829
$0
$465,529
2024
1.7%
$294,625
$178,818
$0
$473,443
2025
1.7%
$299,633
$181,858
$75,000
$556,492
2026
1.7%
$304,727
$184,950
$76,275
$565,952
2027
1.7%
$309,908
$188,094
$77,572
$575,573
2028
1.7%
$315,176
$191,291
$78,890
$585,358
2029
1.7%
$320,534
$194,543
$80,232
$595,309
2030
1.7%
$325,983
$197,851
$81,595
$605,429
2031
1.7%
$331,525
$201,214
$82,983
$615,722
Average:
1.7%
$289,070
$185,213
$50,232
$524,514
(A) Total Annulized Sum of 2021 = $1,031,046 * 10%
(b) Add 2 Maintenance -Tech I [Est. $54,000/yr], 1 Crew Leader [Est. $72,0001
(c) 3/4 Ton Pickup [Est. $38,000], 1-20 Foot Trailer [Est. $18,000], Additonal Misc. Equipment [Est. $10,000]
(d) Total Annual Ammount divided by 12 results in Total Montly Budget
j:\clerical\anna\2020 drainage utility analysis\03_report.docx - 1 1 -
Birkhoff, Hendricks & Carter, L.L.P.
I. STORM WATER UTILITY RATE OPTIONS
A. 10-Year Level Rate Analysis (Base Approach)
In this analysis, the monthly fee for both Residential and Non -Residential lots is calculated on a
ten-year (10-year) level rate by using the average budget over a 10-year period for both the
Operation and Maintenance and Capital Improvements budget. Three (3) different options are
considered
Option 1: Operation and Maintenance monthly budget (Table 5)
Option 2: Capital Improvement Project monthly budget (Table 6)
Option 3: Combining both O&M and CIP monthly budgets. (Table 7)
Tables 5-7 below present the calculate the monthly residential and non-residential fee based on
these three different options.
TABLE 5 - Stormwater Utility Rate Calculation (O&M Budget Only)
Rate Category
Porportional Share
Based on C*A
Total O&M
Monthly Budget
($) (Table 5)
Parcel Count
(#)
Total Area
(ac.)
Monthly Fee
Per Parcel
Monthly Fee
Per Acre
Residential
88.0%
$38,437
8,459
4-76-34
$4.54
^J /
Non -Residential
12.0%
$5,263
353
NLI
$14.93
Public
0.0%
$0
0
N/A
Total:
100%
$43,700
8,459
4,987
TABLE 6 - Stormwater Utility Rate Calculation (CIP Only)
Rate Category
Porportional Share
Based on C*A
Total Monthly
Debt Service ($)
('fable 4)
Parcel Count
(#)
Total Area
(ac.)
Monthly Fee
Per Parcel
Monthly Fee
Per Acre
Residential
88.0%
$49,268
8,459
4-, 4
$5.82
W1 A
Non -Residential
12.0%
$6,746
9
353
NSA
$19.14
Public
0.0%
$0
a
0
Ay'%
N/A
Total:
100%
$56,014
8,459
4,987
TABLE 7 - Stormwater Utility Rate Calculation (Combined CIP +O&M)
Rate Category
Porportional Share
Based on C*A
Total Monthly
Requirement ($)
(Table 4+5)
Parcel Count
(#)
TotalArea
(ac.)
Monthly Fee
Per Parcel
Monthly Fee
Per Acre
Residential
88.0%
$87,705
8,459
®i;644
$10.37
4/A
Non -Residential
12.0%
$12,009
353
$34.07
Public
0.0%
$0
9
0
N/A
Total:
100%
$99,714
8,459
4,987
jAclerical\auna\2020 drainage utility analysis\03_reporl.doex - 12 -
Birkhoff, Hendricks & Carter, L.L.P.
The Calculated Fees shown in Tables 5-7 are the maximum allowable fees for the properties of each
land use classification. The calculated fees assume that the fees shall be fixed for the next five years,
however, the Local Government Code allows for the governing body of the stormwater utility to adjust
the charges from time to time. It is recommended the maximum fee calculation be reviewed and
adjusted, as required, prior to termination of the 5-year period. The update shall reestablish the O&M
budgetary requirements with the possible inclusion of newly identified stormwater capital improvement
projects and shall consider land use developments in the service area.
Based on the calculated fees, we recommended implementation of the following Maximum Fee
R- that include both the Storm Water System Operation and Maintenance expenditures and
the Storm Water System Capital Improvements debt service:
Residential: $10.37 per month
Non -Residential: $34.07 per Acre
B. 10-Year Annual Analysis (Supplemental Approach)
During the review phase of this analysis, the City staff requested we perform a "supplemental"
annualized evaluation of the storm water rate. In this analysis the monthly fee for both
Residential and Non -Residential lots is calculated on a year -by -year annual basis. and utilizes
the annual O&M and Capital Projects Debt Service budgets over a projected ten-year period.
This approach requires a more focused estimate of annual growth in residential units and non-
residential developments. Table IA below is an itemized presentation of Table 1 and presents
the estimated annual growth in residential units and non-residential developments and calculates
the proportional "CA" used for each year of the analysis.
This approach results in an initial lower fee that generally increases over time.
jAclericallanna\2020 drainage utility analysis103_report.docx - 13 -
Birkhoff, Hendricks & Carter, L.L.P.
TABLE 1A - Calculation of Runoff Contribution by Property Category (Annual Estimate)
Residential Units
Non Residential acres
Year
Lots
Acres
(A)
Run-off
"C"
Weighted
CA
Proportinal
CA
Acres
Run-off
"C"
Weighted
CA
Proportional
CA
Total CA
2021
6,250
3,424
0.5
1,712.0
87.98%
260
0.9
234.0
12.02%
1,946.0
2022
6,500
3,561
0.5
1,780.5
87.99%
270
0.9
243.0
12.01%
2,023.5
2023
6,800
3,725
0.5
1,862.5
88.01%
282
0.9
253.8
11.99%
2,116.3
2024
7,200
3,944
0.5
1,972.0
88.06%
297
0.9
267.3
11.94%
2,239.3
2025
7,700
4,218
0.5
2,109.0
88.08%
317
0.9
285.3
11.92%
2,394.3
2026
8,450
4,629
0.5
2,314.5
88.11%
347
0.9
312.3
11.89%
2,626.8
2027
9,217
5,049
0.5
2,524.5
87.93%
385
0.9
346.5
12.07%
2,871.0
2028
9,877
5,411
0.5
2,705.5
88.13 %
405
0.9
364.5
11.87%
3,070.0
2029
10,427
5,712
0.5
2,856.0
88.19%1
425
0.9
382.5
11.81%
3,238.5
2030
10,667
5,844
0.5
1 2,922.0
87.95%
445
0.9
400.5
12.05%
3,322.5
2031
10,667
5,844
0.5
1 2,922.0
87.95%1
445
0.9
400.5
12.05%
3,322.5
The same Three (3) different options are considered
Option 1: Operation and Maintenance monthly budget (Table 5A)
Option 2: Capital Improvement Project monthly budget (Table 6A)
Option 3: Combining both O&M and CIP monthly budgets (Table 7A)
Tables 5A-7A below present the calculate the monthly residential and non-residential fee based
on these three different options.
TABLE 5A- Stormwater Utility Rate Calculation ( O&M Budget Only)
Year
Total Annual
O&M Budget
Amount
(s)
Monthly Rates
Residential
Rate
(per Unit)
Non -
Residential
Rate
(per Acre)
2021
$273,105
$3.20
$10.52
2022
$457,747
$5.16
$16.97
2023
$465,529
$5.02
$16.49
2024
$473,443
$4.83
$15.86
2025
$556,492
$5.30
$17.44
2026
$565,952
$4.92
$16.16
2027
$575,573
$4.58
$15.04
2028
$585,358
$4.35
$14.30
2029
$595,309
$4.20
$13.79
2030
$605,429
$4.16
$13.66
2031
$615,722
$4.23
$13.89
Average:
1 $524,514:::]l
$4.67
1 $15.36
j:\clerical\anna\2020 drainage utility mtalysis\03_report.docx - i 4 -
Birkho.f, Hendricks & Carter, L.L.P.
TABLE 6A - Stormwater Utility Rate Calculation (CIP Only)
Year
Annual CIP
Debt Service
Mouthy Rates
Residential
Rate
(per Unit)
Non -
Residential
Rate
(per Acre)
2021
$373,427
$4.38
$14.39
2022
$373,427
$4.21
$13.84
2023
$373,427
$4.03
$13.23
2024
$373,427
$3.81
$12.51
2025
$746,855
$7.12
$23.40
2026
$746,855
$6.49
$21.33
2027
$746,855
$5.94
$19.51
2028
$746,855
$5.55
$18.24
2029
$1,120,282
$7.90
$25.94
2030
$1,120,282
$7.70
$25.28
2031
$672,169
$4.62
$15.17
Average:
$672,169.29
$5.61
$18.44
TABLE 7A - Stormwater Utility Rate Calculation (Combined CIP + O&M)
Year
Total Annual
O&M
Budget
Amount
($)
Annual CIP Debt
1 Service
Total Annual
Budget
(O&M+CIP)
Mouthy Rates
Residential
Rate
(per Unit)
Non -
Residential
Rate
(per Acre)
2021
$273,105
$373,427
$646,532
$7.58
$24.91
2022
$457,747
$373,427
$831,175
$9.38
$30.81
2023
$465,529
$373,427
$838,956
$9.05
$29.73
2024
$473,443
$373,427
$846,870
$8.63
$28.37
2025
$556,492
$746,855
$1,303,346
$12.42
$40.84
2026
$565,952
$746,855
$1,312,807
$11.41
$37.49
2027
$575,573
$746,855
$1,322,428
$10.51
$34.55
2028
$585,358
$746,855
$1,332,213
$9.91
$32.54
2029
$595,309
$1,120,282
$1,715,591
$12.09
$39.73
2030
$605,429
$1,120,282
$1,725,711
$11.86
$38.94
2031
$615,722
$672,169
$1,287,891
$8.85
$29.06
Average:
$524,514.41
$672,169.29
$1,196,683.70
$10.15
$33.36
j:\clerical\anna\2020 drainage utility anaIysisM_report.docx - 1 5 -
Birkhoff, Hendricks & Carter, L.L.P.
J. Non -Residential Stormwater Detention System Fee Credit
Several non-residential properties in the City of Anna currently utilize stormwater detention
systems (ie. detention or retention ponds) to reduce runoff rates from the developed properties.
An effective, on -site stormwater detention system benefits the City's existing stormwater
drainage system by reducing the rate of runoff from the property to the stormwater system, thus
reducing the required capacity of the downstream municipal utility system. The City may allow
those non-residential properties which utilize an effective stormwater detention system to seek
Stormwater Drainage Fee -Reduction Credit.
We recommend requirement of application for the fee -reduction credits that is to be
administered, approved and maintained by the City. We recommend the fee -reduction be
proportional to the calculated reduction in runoff flow rate provided by the installed detention
system, with a maximum allowable reduction established as an equivalent runoff estimated with
a `C'-factor of 0.5. The calculated non-residential fee rate, $34.07 per acre, utilizes a runoff `C'-
factor of 0.9, and therefore the maximum fee -reduction for a well -performing on -site stormwater
detention system results in a reduced fee rate of $18.93 per acre. The detention system would
require review by a licensed engineer in the State of Texas to provide the calculation results
necessary for the calculation of the actual flow reduction.
It is further recommended that the City inspect those stormwater detention systems credited for
the reduction of runoff flow rate. The facilities must be maintained to ensure performance of the
rated flow reduction. The City may require submission of a maintenance schedule with the
application, for which City -approval and adherence by the property owner would be required.
The City shall retain the powers to revoke the fee -credit upon non-conformance to the
maintenance schedule or if the system is removed or found in disrepair. If the detention system
fails, the fee -credits shall be revocable and subject to back -charges, based on the City's
determination of the failure period and severity.
jAclericahanna12020 drainage utility analysis103_report.docx - 16 -
THE CITY OF
manna
MUNICIPAL DRAINAGE UTILITY
2021 RATE ANALYSIS
BIRKHOFF, HENDRICKS & CARTER, L.L.P.
PROFESSIONAL ENGINEERS
DALLAS, TEXAS
TBPELS Firm No. 526
October 2021