􀁾􀁌􀁾􀂷􀀱􀁾􀁾􀀧􀀠s 􀀶􀁾􀁆􀀭(214) 450-2886..ADDIsoN CITY ENGINEER'S OFFICE ., I.... Post Offtce Box 144 Addison. Ten, 75001 16801 Westgrove MEMORANDUM August 30, 1991 RE: Town of Addison Drainage criteria Manual The Town of Addison contracted with Espey, Huston and Associates, Inc. to prepare a Drainage Criteria Manual that provides a basis for the design of drainage systems within the Town of Addison. The significant aspects of this manual are as follows: 1. Requires new storm drainage systems to provide for the fully developed 100 year storm. 2. Requi res the deveI opers use rainfall intensities based on Hydro-35, which is commonly used throughout the metroplex. 3. Limits the ponding depth in the street to a maximum (depending on the street classification) of six inches. 4. Requires detention/retention ponds when runoff from a development exceeds the capacity of the downstream system. As an alternative to detention/retention, a developer is allowed to upgrade the existing system to accommodate the fully developed flow. These standards are generally consisten. with the practices currently followed within the Town of Addison. staff recommends that the council consider an ordinance adopting the proposed Addison Drainage Criteria Manual. If you concur, please have Carmen place an item on the September 10, 1991 council agenda for their consideration. JRB/rp Attachments: 1. Proposed Addison Drainage Criteria Manual 2. Draft ordinance cc: Carmen Moran, City Secretary ORDINANCE NO. AN ORDINANCE OF THE TOV1N OF ADDISON, TEXAS A/4ENDING CHAPTER 16, STREETS AND SIDEWALKS OF THE CODE OF ORDINANCES, TOWN OF ADDISON, TEXAS, TO PROVIDE FOR ADOPTION OF DRAIllAGE CRITERIA; TO PROVIDE FOR REPBAL; TO PROVIDE FOR SEVERABILITY; TO PROVIDE FOR A SAVINGS CLAUSE; TO PROVIDE FOR PENALTIES; AND TO PROVIDE AN EFFECTIVE DATE. BE IT ORDAINED 8Y THE CITY COUNCIL OF THE TOIvN OF ADDISON, TEXAS: SECTION 1. That Section 16-26 of the Code of Ordinances, Town of Addison, Texas, is hereby amended to read as follows: Sec. 16-26. Adoption of Drainage Criteria. There hereby adopted standard specifications for drainage construction and drainage criteria, as the rules and regulations governing the construction of drainage systems and streets, roads and alleys in the City. The specifications adopted hereby are attached to the ordinance from which this section is derived as Exhibit "A" and made a part hereof for all purposes. The original copy of the standard specifications shall be kept with such ordinance and with the other ordinances of the City at the Town hall and shall be made available for public inspection during regular business hours of the City. It shall constitute an offense for any Person to violate any of the requirements contained in such drainage criteria. SECTION 2. That all ordinances of the City in conflict with the provisions of this ordinance be, and the same are hereby repealed and all other ordinances of the City not in conflict with the provisions of this ordinance shall remain in full force and effect. -1 SECTION 3. That should any paragraph, sentence, subdivision, clause, phrase or section of this ordinance be adjudged or be held to be unconstitutional, illegal or invalid, the same shall not affect the validity of this ordinance as a ,,,hole or any part or provision thereof other than the part so decided to be invalid, illegal, or unconstitutional. SECTION 4. Any person, firm or corporation violating any of the provisions of this Ordinance, shall upon commission be deemed ]uilty of a misdemeanor, and shall be subject to a fine not to exceed the sum of Five Hundred and no/lOO Dollars ($500.00) for each offense, and each day such violation continues shall constitute a separate offense. SECTION 5. That Chapter 16, Streets and Sidewalks, of the Code of Ordinances, To\vn of Addison, Texas, shall remain in full force and effect, save and except as amended bv this ordinance. SECTION 6. This ordinance shall take effect and be in force from and after its adoption as provided by law. DULY PASSED BY THE CITY COUNCIL OF THE 􀁔􀁏􀁾􀀱􀁎􀀠OF ADDISON, TEXAS, this day of _____________ , 1991. ATTEST: CITY SECRETARY C17-SS ESPEY, HUSTON & ASSOCIATES, INC. Engineering & Environ"!ental Consultants December 23, 1989 Mr. Ron Whitehead City Manager's Office ToWn of Addison Post Office Box 144 .Addison, Texas 75001 EH&A Proposal No. 89-0822 Re: Drainage Study Dear Mr. Whitehead: Reference is made to your letter dated November 7, 1989 regarding a proposed study related to drainage problems in the Town of Addison. We have received and reviewed the Ginn Report' entitled ''Preliminary Engineering Study for Drainage Improvements: dated October 1989. We secured a copy of the recently completed report on December 23, 1989. In your letter, you have requested that we undertake the following tasks: 1. Review the Ginn Report and comment on the recommendations proposed. 2. Outline policies/standards to be implemented for existing drainage problems. 3. Outline drainage standards for future development in Addison. The scope for Task No. 1 would consist of the following activities related to the Ginn Report on localized drainage problems: • Review each problem in the field to obtain problem definition. • Review existing plans and calculations developed in the report. • Review alternative solutions and cost estimates. • Present concurrence with proposed solution or an alternative solution for each problem area. With respect to Task No.2, we understand that some of the drainage problems which currently exist may have been avoided with adequate drainage policies in place by the City. We will review each case identified in the Ginn Report individually and make recommendations to implement drainage policies for these specific cases. The third task is a very important and necessary tool fur the Town to control the orderly development of drainage facilities in the future. As you know, when communities urbanize, drainage problems become more acute, as increased levels of development yield more runoff. Many problems can be avoided through the implementation of formalized drainage policies. 17811 Waterview Parkway· Dallas, Texas 75252' (214) 669-9600 ESPEY, HUSTON & ASSOCIATES, INC. Mr. "Ron Whitehead December 23, 1989 Page 2 Espey, Huston & Associates, Inc. (EH&A) has authored numerous "Drainage Criteria Manuals" throughout the State of Texas. This provides the Town and development community with a 'known set of drainage standards, enforced throughout the Town which, if properly administered, will preclude the possibility of flooding for an acceptable frequency storm. This 'policy manual should govern the planning, design, construction and operation of storm drainage facilities within the Town of Addison and within all areas subject to the Town's extraterritorial jurisdiction. Definitions, formulae, criteria, procedures and data will be developed to support this policy. We have previously reviewed with you several samples of manuals authored by EH&A Fee Schedule For the above described services, we would propose the following schedule of charges: • Task 1 -Review and comment on the Ginn Report $ 4,000 • Task 2 -Outline policies/standards for existing drainage problems $ 3,500 • Task 3 -Prepare Draiuage Criteria Manual which outlines drainage $18,000 standards for future development in Addison Further, as you requested, we have investigated the potential for State funding for the above described activities. As you know, Section 15.405 of the Texas Water Code authorizes the Texas Water Development Board to provide grant assistance from their Research and Planning Fund to political subdivisions to develop reconnaissance-level plans for flood protection. The Board can provide funding not to exceed 50% of planning costs. Unfortunately, it does not appear that the activities outlined in this letter would be eligible. We hope this information proves useful. We would be happy to discuss this proposal further at your convenience, and look forward to proceeding with the work. Very truly yours, oJJ 􀀶􀀧􀀯􀁾 William B. Moriarty, 􀁐􀀮􀁅􀀮􀁾􀀠Vice President WBM:bls --I I I I CHAPTER V DRAINAGE I I Definition: Runoff is a quantity of water passing any given point of the drainage course as a result of preI cipitation. Runoff may be properly referred to as storm I water, flow, or discharge.I Rainfall: Rainfall intensities used for this preliminary report were taken from the U.S. Department of Commerce Weather Rureau, Technical Bulletin No. 25. The U.S. DepartI ment of Commerce Weather Bureau, Technical Paper No. 40 will probably be utilized in the final design for the calculation I of rainfall intensities. The Rational Method: For drainage areas that are not I complex and have an area of less than 1,000 acres the rational I method for determining runoff is recommended. Formula: The rational method is based on the formula: I Q = CIA where Q is the rate of runoff in cubic feet per second (CFS); C is the coefficient of runoff which is the1 ratio of the maximum rate of runoff to the average rainfall I intensity. As a ratio, C has no unit. I is the average , intensity of the rainfall in inches per hour for the duration I 1 ••• under consideration. A is the area in acres contributing• I to the runoff. NOTE: The unit of Q as expressed by the I formula is inches per hour per acre. However, this rate differs from cubic feet per second by less than It and the I unit of cubic feet per second is commonly used. Coefficient of runoff: The coefficient of runoff represents the effects of infiltration, detention, evapeI ration, and storage. Some of the factors that effect the 􀁾􀁯􀁥􀁦􀁦􀁩􀁣􀁩􀁥􀁮􀁴􀀠of runoff are permiability of the soil typeI and the amount of vegetation, slope of the surface and I future land uses. Values of C are listed in the following table: I LAND USE RANGE OF C I Residential 0.3 -0.6I Commercial 0.7 -0.9 I Industrial 0.6 -0.8 Apartments 0.6 -0.8 I Shopping Centers 0.8 -0.9 Paved Areas 0.9 ' I I Time of Concentration: The time of concentration is the time required for all parts of the drainage area to I I I • • contribute flow to the point under consideration.• Overland: The time of concentration for overland flow can be 􀁾􀁥􀁴􀁥􀁲􀁭􀁩􀁮􀁥􀁤􀀠by the use of various nomagraphs• I or can be computed by the formula K ; 􀁌􀁾􀁾􀀠where L is I the length of the most distant contributing point and 5 is the slope. Velocity: Considering the anticipated grbwth along I Addison Road a velocity greater than 5 feet per second is recommended.I I Minimum Time; Minimum time of concentration is 20 minutes. Design Frequency; The design frequency is a frequency I of the design runoff or the rainfall return period. A des ign frequency is based on the importance of the facH ityI I under design consideration or possible flood damage resulting from an·overflow of the drainage facility. Design Criteria: Due to the fact that Addison Road is I located primarily on a ridge running in a north/south direction, most of the water that falls on the roadway will either beI I discharged east to the White Rock drainage basin or to the west to the Trinity drainage basin. Also, due to the fact that there are no low lying areas where water could accumuI late and cause possible flood damage, the design criteria I I I I • was selected as a basis of design according to the fOllowing:• I (intensity) was selected for a 20 minute duration on the I 2S year storm frequency 􀁣􀁾􀁲􀁶􀁥􀀮􀀠The coefficient of runoff • was selected as 0.85 This represents a compromise between all paved areas and commercial and apartment-type construction. I The following table shows the quantity of discharge for the various draina:;e areas as shown on the attached maps. The I values of QZS range from 9 to 258 cubic feet per second. I Drainage Area Time of 125* No. Acres C Total CA Concentration In/Hr I I 1 2S 0.85 21. 25 20 minutes 5.15 109 Z 22 0.85 18.70 20 minutes 5.15 96 3 2 0.85 1. 70 20 minutes 5.15 9 I 4 22 0.85 18.70 20 minutes 5.15 96 5 40 0.85 34.00 20 minutes 5.15 175I I 6 55 0.1l5 46.75 20 minutes 5.15 240 7 19 0.1l5 16.15 20 minutes 5.15 83 8 59 0.85 50.15 20 minutes 5.15 258 I 9 2 0.85 1. 70 20 minutes 5.15 9 10 -=-2􀁾􀀠0.85 1. 70 20 minutes 5.15 9I TOTAL 248 I *Technical Paper No. 25 I I l3 • • • • • • • I I • • I I I I • I I I -\\;, ), \' , \ \ \' ..... /'/􀀬􀁜􀀬􀁾􀀢􀀬􀀭􀀺􀁾􀁾􀀮􀀠􀀯􀁾􀀭􀀧􀀭􀀽􀀭􀂭\ ; \ i. \\ , \\ \ 'v-' --.; LEGEND y="y"Inlef • =Curb Inlet \ \ '. \ '-.' \ '. '• i, .-'-" .' ,i 􀀢􀀧􀁲􀁾􀀱I . • 'J 1 ! ADDISON ROAD DRAINAGE AREAS AND CONSULTING 􀁩􀁍􀀻􀁉􀁎􀁾􀀧􀀺􀁅􀁉􀁩􀀧􀁓􀀠DALLAS, TEXAS SCALE: 1"'500' 1978'll-I 'A • • • • I I I I I I I I I I I I I I I LEGEND y,,"y"lnlel ." Curb Inlet SCALE: [",sod '" CITY OF ADDISON ADD ISON ROAD DRAINAGE AREAS GINN AND STACY, INC CONSULTING ENGINEERS DALLAS, TEXAS 1978 • • • • • • • • I I I I I I I • • I • ,'" LEGEND ! , '" , " " "􀀧􀀬􀁾,r, 11 , I", ," " , ,,, ,,, , , , ' , " , , :;, .".. Y=" y" Inlet.= Curb Inlet t CITY OF ADDISON ADDISON ROAD DRAINAGE AREAS seA LE: 1":50d GINN ANOSTACY, INC CONSlILTING EN61NEERS DALL AS, TEXAS 1978 16 0 October 2001 􀁉􀁾􀁟􀀮􀀺􀀮􀀮􀀮􀀮􀀮􀀮􀀮􀀮􀀮􀀮􀀮􀀮􀀻􀀺􀀮􀀭􀀮___· __􀁾􀀮􀁾􀀬􀀬􀁾􀀢􀀡􀁾􀁟􀀧􀁴􀁌􀀮􀀭􀀮􀀧.. -<, ,-" 􀀮􀀭􀀭􀀧􀀭􀀭􀀭􀀧􀀭􀀮􀀭􀀻􀀮􀀭􀀻􀀮􀀮􀀮􀀻􀁾􀁾􀀭􀀮􀀭􀀭􀀭􀀺􀀮􀀮􀀮􀀺􀁾􀀺􀀭􀀧􀀭􀀧􀀢􀀭􀀭􀀭􀀭􀀭􀀭 􀀮􀀠 10:30am FEMA 10:00am DART System Plan 9:00am Kim Forsythe Representative-Dale I w/Jay Kline (Town. Property/Arapaho Hoff-National Rood Hall Conf Rm) !0:00am WORDING ON 10:30am Updated: ClP (TH . 2:00pm Marsh Ln. AGREEMENT C Conf-Room) Construction and 10:00am DRAFT AGENDA 12:30pm GOLF WITH THE Easement MTG. GUYS!!!! Alternatives (Service 3:00pm REVIEW SECURITY in dty managers co 12:00pm TOASTMASTERS-FIRE; DAY ALL 10:ooam pre council meeting STA.1 10:308m Updated: ClP (TH 11:30am Meet w URSIMidway 1:00pm 7-11 and Jack in the Conf-Room) 1:30pm Updated: Sasaki & Box plan. for Addison 3:30pm Arapaho Road Bridge Road (Service 7:30pm COUNCIL MEETING Center) :. ,.,: '.' :';.,. 􀀧􀀬􀁟􀁾__,_,,__'_:.: 􀀧􀀬􀁟􀀬􀀻􀀬􀁟􀀺􀁾􀁟􀀬􀀬􀀬􀁾􀂧􀁬􀀬􀀠___.:____ cc 2:00pm GIS "DUCKS IN A '9:00am MONTHLY crp Conf-Room) 10:30am Updated: CIP (TH ROW MEETING" PROGRESS MTG. (TH (ADDISON SERVICE CONF. ROOM) em. 16801 lO:OO8m DRAFT AGENDA(TH WESTGROVE) CONF RM) 10:30am Updated: erp (TH 10:00am pre council meeting I 8:00am TSPEIFREESE Conf-Room) to discuss the up, NICHOLS coming council I 10:00am post council meeting meeting 7:30pm COUNClL MEETING 10:30am Updated: OP (TH 6:00pm HALLOWEEN BASH 11:30am MERITORIOUS Coof-Room) (MC) SERVICE LUNCH (F.S.l) 6:00pm PO HALLOWEEN EVENT @4010 B pre CONCRETE CONF. M• 1 7 •14 15 21 22 2. 19 9:008m Review Center) 11:30am PW STAFF LUNCH MEETING October 2001 T W T F •2 4 5 6,.• 11 12 13,.• 17 18 19 20 23 24 25 27 31.. •• NiM!liYIbet 2001• M T W T -----_. 5 6 7• 1•11 12 I. 14 15,.1S :ro 11 25 16 27 28 2' " F •􀁾􀀲􀁾􀀠􀁾􀁾􀀢􀀠3 9 10,. 17 13 2'3. FOR TODAY 1:30pm MEETING WICT & UNITED WAY PANCAKE BREAKFAST 1:30pm MEETING WICT& \ 􀁃􀀢􀀢􀀢􀁾􀁜􀀺􀀠-'. ,-<, 1:30pm MEETING W/CT 1:30pm MEETING WICT & 9:00am TODAY......IN WYUE... . 􀀬􀁟􀀬􀀺􀀮􀀮􀁣􀁾􀂷􀁟􀁣􀂷__-"·h'"',,.·-· TIME 8:00am DO Michael Murphy 1 10/04/2001 No-rember 2001' S M T W T f S S M 1 2 3November 2001 4 5 6 7 • • LO , •11 12 13 " 15 ,. 11 • ,.,. 19 20 21 22 2' '" " 17 2S 26 27 26 2' •• l3 24 30 .. __ Thursday November 11 Friday 􀁾􀀠8:00am LUKE @roNCRETE roNF. -----. ... 9 lO:30am Updated: CIP (TH Conf·Room) J__ 􀁾􀀠􀀡, 7 􀀮􀁾􀁉􀀠-----..... _________.___ J .. _ ,-------, 1:30pmMEETINGW/CT& ---i ---,-12 B .. --_ · _____ ·_·________1__ --. ---1--------_.10:30am Updated: OP (TH lO:OOam pre coundl meeting Conf-Room) in city managers ' -conf. roDm to discuss upcoming council me 10:00am pre council meeting in city! managers conf_ room to discuss 10:3Oarri-Updated:QP(TfI-------------------Conf-Room) 9:00am MONTHLY C1P PROGRESS MTG. [TH CONF_ ROOM] ! ____... -f MEETING wlcr 􀀦􀀭􀁾􀀠------____..􀁾 􀁌􀁦􀀠-------.____.._ 1:30pm MEETING 10:30am Updated: CIP (TH <0 10:00am pre coundl meeting