Loading...
5105-91ti •. ORDINANCE NO!__5105-9 AN ORDINANCE OF THE CITY OF CLEARWATER, FLORIDA, RELATING TO THE LAND DEVELOPMENT CODE; CREATING SECTION't' 1360-031; CODE OF ORDINANCES, ADOPTING STANDARDS AND SPECIFICATIONS FOR STORMWATER DETENTION FACILITIES,,'-AND PROVIDING FOR PAYMENT IN LIEU THEREOF; AMENDING SECTION 137.010; CODE OF ORDINANCES, RELATING TO SITE PLANS AND STORMWATER DETENTION REQUIREMENTS FOR DEVELOPMENT PROJECTS FOR WHICH SITE PLAN APPROVAL IS REQUIRED; PROVIDING AN EFFECTIVE DATE. WHEREAS, Policy 23.1.4 of the comprehensive plan of the City states that the City shall adopt a stormwater ordinance requiring redeveloped sites, other than single-family residential areas, to incorporate water quantity and quality controls consistent with new development regulations, recognizing that case-by- case limitations may call for partial controls, off-site improvements, or payments in lieu of improvements to achieve this goal; and WHEREAS, the City Engineer has prepared development standards and design specifications relating to stormwater drainage and detention, known and referred to as "Design Criteria, Storm Drainage--City of Clearwater," a copy of which is attached to this ordinance as Exhibit A and incorporated herein by reference, pursuant to which the developers of both redevelopment projects and initial development projects are required to attenuate stormwater flow and provide certain water quality features; and WHEREAS, the development standards and design specifications relating to stormwater drainage and detention are consistent with and satisfy the requirements of Policy 23.1.4 of the comprehensive plan of the City, and should be adopted by ordinance; now, therefore, BE IT ORDAINED BY THE CITY COMMISSION OF THE CITY OF CLEARWATER, FLORIDA: Section 1. Section 136.031, Code of Ordinances, is created to read: Sec. 136.031. Stormwater detention facilities; standards and specifications adopted; payment in lieu thereof. (1) The development standards and design specifications relating to stormwater drainage and detention, a copy of which is attached hereto as Exhibit A, are hereby adopted and incorporated herein by reference. Copies of such standards and specifications shall be maintained on file in the office of the City Clerk and in the Public Works Department. The standards and specifications shall not be amended except by ordinance. (2) Stornmater detention facilities required by the standards and ?E specificiations but which, in the opinion of the city engineer, would be impractical or ineffective because of the size of the property, the space available for stormwater detention facilities, soil conditions, or other site related conditions, may be waived at the request of the developer upon payment to the city of a fee in lieu thereof which shall be used by the city solely for drainage improvements in the drainage basin in which the property is located. Such fees shall be determined by the market value of the area of land which would have otherwise been required to accommodate a stormwater detention facility, according to an appraisal made by the city or by a property appraiser holding either an MAI or SRPA designation, at the option of the property owner, and by } the construction value of the stormwater detention facility that would have otherwise been provided, such construction value to be determined by the city engineer. Subject to the approval of the city engineer, the developer may install a portion of the required stormwater detention facilities and pay the city a fee in lieu of installation of the remaining portion of the facilities. Section 2. Paragraph (4) of Subsection (g) of Section 137.010, Code of Ordinances, is amended to read: Sec. 137.010. Site plans. k * * * (g) Design guidelines for site plan review. It is the purpose of these design guidelines to supplement the standard requirements of the comprehensive indi'yldua-'l land use plan and land development code in a manner that recognizes the need to tailor the land planning process to the unique features of each site, while preserving the right of reasonable use of private property based upon the uses permitted under- the land use plan and ;'0W*r4 atlas elassif4eatiens assigned to the ppepe ty The followings shall be given full consideration in the °ratie^---and review of site plans required under this section. Before Furt herme-beef ore any final site plan is granted approval (whether conditionally or unconditionally) , it shall first be estab- lished that such plan is consistent with the design guidelines of this section. If l+#4ei+ it is determined that a final site plan does not satisfactorily comply with one or more, in whole aF in-"rt, of any of the design criteria contained herein, the city shall have the authority to deny the site plan. Design guidelines to be considered shall include the following: 2 S/OS' 7/ • r 4 1 (4) Streets, drainage and utilities. Site plans shall be so designed as. to provide for adequate streets, water supply, sewage disposal, refuse collections stormwater detention and other public service and utility facilities, as follows. that- these measures haye beeR adequately addressed inelude the-49119wing: a. Citywide water supply and sewage treatment capabilities, by district where applicable. b. Water mains, fire hydrants and water meters. C. Sewer mains and manholes. d. Gas mains, where applicable. e. Provisions for refuse disposal, including container location and access thereto. f. Easements for all utility lines. g. Stormwater Leeation, eapaeky and design of stermwater detention facilities, berms-tethe--site --and the watershed or basin, or payment in lieu thereof as provided in section 136.031 heron. The location, adeguacy, and design of stormwater detention. facilities shall be evaluated both as to the site and the watershed or basin. The responsibility of the owner and the owner's successors in title or interest for the maintenance and appearance of stormwater detention facilities shall also be established. T h RespeRsibi 1-ity er- ""'nten mee and ppear a!TnV of r f _r.}nrngater- detention f ei l 444- h 4. Sufficiency of adjacent streets. All of the above requirements fac-ters shall be satisfied `{utter- ine4 consistent with the objectives of the utility plan and current development standards and design specifications of the city engineer, and the standards and specifications relating to stormwater drainage and detention set forth in section 136.031. it shall be the objective of this guideline to assure that adequate service capacity r r is available and that utility, street and drainage systems are appropriately designed for the proposed development site in relationship to the larger systems entering and leaving the site. ?rflame,- detentirtioT-TLTCTf?TGTE.:. T`?rrr?i`cr-i? epinien of the rite e1"ni%e?r, woufd--be i i raetealor,_ ineffeeti-Yt `?ti -[?use of the size of the ertJ i spaee available for +.vntn'??tE•P-?E?e{?t-rcrrr-rae-r-r-rsies, 3 S/aS' J/ • • w of the deyelopep upon payment to the eity ef a fee W lieu ay 3 ^ • site related eandk4qns, may be deleted at 06 request thereof wh4eh shall II e I; 1 O tieR 9f p of the faei!446s . Section 3. This ordinance shall take effect immediately upon adoption. PASSED ON FIRST READING AS AMENDED : PASSED ON SECOND AND FINAL READING AND ADOPTED Attest: I `? rte Cynt Gou City Clerk Approved as to f and correctness: M. A. Ga rait? City Attorney August 15, 1991 Mayor-Commissioner u u orm Jr. 4 ,570,5-- 7/ August 29, 1991 r w D-ESIGH CRITERIA CITY OF CLEARWATER L:l STORM DRAINAGE :ik:l''I'F:hllfk:k2 I?)t) STORZiWATER MANAGEMENT DESIGN CRITERIA 1. GENERAL: All construction shall comply with the City of Clearwater Contract Specifications and Standards Manual. All stormwater facility designs must be designed and certified by a Florida Registered Engineer. Record drawings shall be submitted and certified by a Florida Registered Engineer before final acceptance of project. Design Frequency (a) - 10 Year - storm systems, culverts (b) - 25 Year - channels and detention areas with outfalls (c) - 50 Year - detention areas without outfalls (d) - 100 Year - detention areas without outfalls which when capacity is exceeded overflow onto private property .' ..IP Runoff Coefficients: Ponds, lakes and detention area (wet or dry) 1.00 Buildings, paved areas, and other impervious areas .95 Turfblock .45 Green or pervious areas .20 Design coefficients shall be obtained by using the above coefficients on a weighted run off method for both pre-development and post-development. 2. STORM DRAINAGE: Detention areas must be built before storm sewers are installed. Slopes shall not be steeper than three to one (3 : 1) and shall be protected from erosion by sod. Time of concentration Time of concentrations to first inlet on a system shall be determined by using velocity of runoff chart. (Chart attached). A minimum time of 15 minutes to first inlet shall be used. .-P. = a SEPTEMBER - 1991 .J 1 i --+q..+-.•....-o.. :.:?.iwi.. ? .:??, ...,?:kt.....?. - ... .,. '" ,er5, u c ? .. e- .. ::'; '.i'. '.i,?? ?F : ^?. ?• r??t,7,ti,?:???. .?; ::,t7a,.,. rw?rrr:nn.,:rrr:' ..'.?__,t;°'•r?s.rK}.,•.. 3. STORM SEWERS. INLETS. AND STREET DESIGN PERTAINING TO WATER FLOW Unless specifically approved by the City Engineer, reinforced concrete pipe shall be used in all easements and street rights-of- way. Minimum size shall be 1511 diameter. Design frequency - 10 year storm. Mannings Roughness coefficient for storm pipe: 0 (a) RCP N 1511 - 3011 inclusive .013 3611 - 4811 11 .012 5411 - up .011 (b) CMP or Aluminum .023 ' Asphalt coated .018 (c) PVC Storm Drain Pipe .009 The slopes for culverts used as storm sewers shall produce a velocity within the following limits: Maximum minimum CMP 10 f.p.s. 2 f.p.s. RCP 12 f.p.s. 2 f.p.s. Standard hydraulic gradient elevation shall be minimum of 1.0 foot below throat of inlet or manhole. i Minimum Culvert Size: (a) - Pape - 1511 (b) - Box Culvert - 31 x 31 Maximum length of pipe without access structure: k (a) - (1511 - 1811) Pipe -,350 ft. (b) - (24" - 3611) Pipe - 400 ft. (c) - (4211 & cover & all box culverts) - 500 ft. SEPTEMBER - 1991 2 :? ;}'?"ygffi?????M?`e???k;~krk?;{.?+k?Fk?.fdc• rye .,•r.-. ?n.;i,,..?,i ;?••.t'?:k?:r;,+•A• "+.? :.9.?.?:.+fi?ide"•.:r-: ;a;l'.y,.;,?.-y.?i°t? t, < !ri ! 1. 4. NLETB AND MANHOLES: Vertical throat opening for inlets shall be 511. Inlets and manholes will be designed so as not to have standing water when not functioning. All inlets to have manhole lids in accordance with city standards. Inlets are not to be placed in curb return. Pipes are to be out flush with inside wall of inlet. Subdrain shall enter structure a minimum of one foot above invert and 2' Gtr below top of structure. When pipe diameter exceeds 3011,. inlets shall not be used as junction boxes, limit 3 pipes per inlet. For design purposes inlet capacity should be assumed as follows: Grate Inlet * - 4 CFS (No Wing Type * - 5 CFS 511 Throat (Single Wing Type - 7 - 8 CFS (Double Wing Type - 9 - 10 CFS * - Subject to City Engineer's approval only. Standard inlet wings shall be a minimum of four feet in length as per City Standards. 5. STREET DESIGN: Generally gutter water should not be carried for distances exceeding 600 feet. Except as where impractical, channeling water across intersections will not be allowed. Normal Grades - .5% up to 2% Steep Grades - greater than 2% Inlet Spacing - 600 ft. - 400 ft. I SEPTEMBER - 1991 3 STREET DESIGN: (continued) Where grades exceed 2t, a 6' wing will be required on the inlet. Grades less than 0.5% are subject to City Engineer's approval only. A minimum of 0.5% grade shall be required for asphalt drives and parking lots. Right-of-way shoulders shall be sodded three feet behind curb and remainder, graded, seeded, and mulched. Mulch to be dry or green per F.D.O.T. current standard. 6. HEADWALLS: All inlet and outlet pipes shall be provided with a headwall, mitred end section, or flared end section. Headwalls shall be reinforced concrete. Pinned Sand/Cement bag structures built in accordance with City of Clearwater specifications ma? be permitted only for temporary use. All outlets shall have an appropriate apron to prevent erosion. 7. CHANNELS AND SWALES: Roughness Coefficient - for a channel with maintained vegetation is .030 to .035. Normal channel depth shall not be within 10% of critical depth. When velocities exceed maximum allowable values energy dissipators shall be provided. Plans shall include undeveloped areas, pre- development drainage, and pre-development discharge at key design points such as channels, existing ponds, sloughs, etc. Also post- development calculations for storm runoff and proper detention shall be determined. Type of Soil Maximum Allowable in Flow Line . Velocity! _Lf.1O. s.) Fine Sand 1.5 Sandy Loam 1.8 Silt Loam 2.0 Firm Loam 2.5 Fine Gravel 2.5 Stiff Clay 3.8 Coarse Gravel 4.0 Hardpan 6.0 Major channels .(Q greater than 30 CFS) shall have a five- foot bottom width. Drainage swales normally will not be permitted along rear lot lines. Swales shall be vegetated and designed for a 50 year storm. 4 SEPTEMBER - 1991 $ . STOItM WATER_DETENTION: This policy is to insure that runoff will not be increased beyond its present state by development. It is also intended to protect the quality of receiving waters in the City from additional pollution resulting from new development. The design frequency shall be a 25 year storm based on rainfall intensity graph for the Clearwater area. The duration may be obtained from the Rational method for areas up to 10 acres. Design variations may be considered for areas less than one acre. The runoff coefficient differential, DELTA C is obtained by subtracting pre-development coefficient from post--development coefficient. For projects greater than 10 acres, systems design must incorporate the U.S. Department of Agriculture soil conservation Service Modified Unit Hydrograph, or equivalent as determined by the City Engineer, in conjunction with a SCS Type III rainfall distribution curve. For average watershed slopes less than .5%, use of the Del Mar Va Unit Hydrograph, in conjunction with the SCS Type III Rainfall, Distribution Curve, will be required. In the case of redevelopment of land upon which no stormwater attenuation or water quality feature exists, or upon which the existence of such features do not meet the standards applicable at the time of redevelopment, the redeveloper will be required to provide facilities in a manner similar to an original developer and in proportion to the extent to which the site plan of the property is affected or disturbed by the redevelopment. In the methodology for calculating stormflow from property undergoing redevelopment, the pre--development volume of runoff will be calculated by the use of a Weighted Runoff Coefficient taken from the following table: PROPERTY DESCRIPTION* WEIGHTED COEFFICIENT OF RUNOFF** Undergoing redevelopment and not 1/2 Actual contributing to an existing flood- in roblem *** Undergoing redevelopment and .20 contributing to an existing floodin roblem Undergoing redevelopment and 1/2 Actual contributing to an existing flood- ing problem for which an attenuat- ing stormwater management project is under construction * City Engineer shall be the determining authority of the Property Description ** In no case shall the coefficient be less than .20 ** To be applied only to area of property undergoing alteration *** Situation wherein property damage occurs in a 25 year - 24 hour storm SEPTEMBER - 1991 5 The City of Clearwater standards relative to the provision of water- quality features are, by this reference, the same as the Southwest Florida Water Management District's, excepting that where SWFWMD may rule that no water quality features are required, the City's standard shall require the provision of treatment of 1/2 inch of rainfall as applied over the entire area of a development project and 1/2 inch as applied over the portion of the site plan undergoing alteration in the case of redevelopment. Qi Ar) = Aare The design hydrograph is an isosceles triangle with a time of concentration equal to one half of the duration. Detention design shall incorporate a minimum time of concentration of one hour and a 25 year storm intensity. The outfall shall be G restricted to accommodate the pre-develop- ment flow with appropriate overflow facilities for larger volumes. Detention ponds will no longer require one foot of CCMCSKTA ETON f (Sec,} freeboard. 1 OVAATIOM Volume of detention may be established by multiplying time of concentration times DELTA Q providing the outlet control structure (weir, pipe, etc.) is designed to restrict other than pre-development Q. An outfall design allowing less than the pre--developed Q to pass is acceptable if storage is provided. Discharge to Lake or Wetland In situations where the pre-developed Q abuts a lake or wetland, the developer may store additional runoff above that required for water quality treatment in the wetland subject provided that the following conditions are met: Wetland with positive outfall has the capacity to store a 25 year design storm. t Wetland with no outfall has the capacity to store a 50 year design storm. Wetland has sufficient capacity to absorb additional runoff. All areas on or off site contributing to a wetland shall be included in the design. Runoff discharging directly to the wetland shall be transmitted via grassed swales. Runoff from lots abutting a wetland shall be collected in an interceptor swale designed to drain dry in less than 24 hours. The maximum design high water elevation of the wetland shall be one foot below the lowest floor elevation around the wetland or one foot below the flow line of the nearest adjacent road, whichever is lower. The design wetland elevation shall be determined by the inflow and outflow hydrograph method. The impact to the wetland system will be taken into consideration when reviewing these applications. Those areas directly outfalling tidal salt water basins will be reviewed for water quality impacts only. SEPTEMBER - 1991 6 Pk Wet detention/retention systems are those that under non storm conditions are designed to have a standing pool of water. The design shall be in accordance with City Detail Index #227. All wet systems shall incorporate a vegetated littoral shelf over 35% of the areal cover of the pond under normal conditions. Drawdown may include an underdrain system, natural percolation or slow bleed down system. Underground vaults are not allowed as water quality facilities and are permitable for water quantity storage only as specifically allowed by the City Engineer. Dry Detention systems Dry detention systems are those that under non storm conditions are dry, ie., has a grassed bottom and side slopes that can be mowed. These systems shall be designed with no steeper than 3:1 side slopes, preferably no deeper than three feet deep and drain dry within 24 hours or less. The side slopes and bottom shall be sodded. Drawdown may be accomplished by the use of underdrain according to city specifications or by percolation if the soil conditions permit. At least one soil boring showing soil profile and the seasonal high water table shall be provided with the site plan. The soil boring shall be located at the center of the proposed detention area. Wet Detention Systems Detention Pond Walls The use of vertical walls on the sides of detention ponds is discouraged and will not be permitted except as may be specifically approved due to reason of undue hardship developer. In no circumstance will vertical walls on ponds be permitted adjacent to rights-of-ways, along boundaries of adjacent parcels of land, on more than a detention pond, or any side of a pond serving only quality facility. 9. SUBMITTALS P to the detention the two sides of as a water In addition to submitting complete plans and specifications, the Engineer shall also submit the following: A. - Drainage calculations or computations including hydro- graphs for any detention areas, retention ponds, complete with cross sections. B. - A scale map or plat showing each subdivision drainage basin, as an aid for review of the proposed work. A minimum of 50 feet of topographical survey shall be required adjacent to the perimeter of the proposed site. SEPTEMBER - 1991 7 C. - Profile of hydraulic gradient for storm pipe sygtem. D. - All pertinent information of adjoining properties affected by stormwater from site such as finish floor elevations of buildings, streets, channel or receiving waters to the final outfall. All adjacent property draining onto the proposed site is to be shown on the site plan. Before project is accepted by the Public Works Department, a Registered Engineer must submit written verification that the project was constructed in accordance with approved construction plans. 10. ATTACHMENTS: Rainfall - Intensity/Duration - Clearwater. This Rainfall Intensity Graph shall be used for 10, 25, and 50 year storms. velocity of Runoff - for use in determining intensity for above grade runoff. Drainage Design computations - suggested for working out drainage "J' computations showing required information for submittal to city of Clearwater for approval. Throttle T e Concrete outlet for Detention Ponds - Index No. 225 Dry Detention Overflow Outfall Structure - Index No. 225--A Underdrain Detail. Non-Roadway - Index No. 205. - sheet 3 of 4 Wet Detention/Retention Pond - Index No. 227 subdrain Detail for Dr Detention Areas - Index No. 236 ?A a SEPTEMBER - 1991 VOLUME 2-PROCEDUF]WPlorida Department of 'transportation Drainage Manual t? ' A 625-040-205-a Page 78 of 98 rte- ?r a1 co r- to u'1 ? m N Q m co i~ co Ln C7 N - 7 1 N - - r - I L L Y 7 Q y r il l r ? '.. ? ?T. .y' .ti" " r1 Q S V C U7 Q 117 i 7 r' d U 7 a r7 - - Q 0 3 N ? 4 CC cD C p t$ O N & -L A _ .a I A (n W - .1 C J-, m - - ?, {.ice - - o Q I H fi ff i ffi tn C) (n co I- W U) -T Cl) C14 0 0) co r, (D l t co unaH Had S3H3Ni NI A-1ISN3.LN1 11VJNIV8 n G W = a M C. 2 '? ILL CE I 1 f 1 1 1 i 1) inn co r 8o r;•' ,' h Vs s W 1 rz I 7O C u G 6u u L L z C 0 >- Cc I l i •/ 1 1 , f l 1 1 1 , f l 1 1 1 1 1 , 1 1 1 r l 1 + 1 1 1 1 1 l l r 1 , I r l 1 1 1 1 , 1 1 1 1, 1• I I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1, 1 1 1 1 1 1 1 1 r 1 1 1 1 1 1 • 1 1 1 1 1/ 1 1, 1 1 1 1 1, 1 I I I I 1 { r 1 1 1 r 1 v I 1 1 1 , 1 , 1 I 1 , 1 1 1 1 1 1 1 1_ 1 I, 1 1- - ? - -_ I 1 • • 1 1 1 1 1 1 1 1 1 I 1 I i+ ! 1 1 1 ? 1 1 7 1 1 ( 1 1 11 t, l I r l 1 1 1 1 ! 1 / , 1 { r 1 1 ' , 1 1 • • ' 1 1 1 I 11 , 1 1 1 f 1 1 1 1 1 1 1 - 1 1 1 1 I /, 1 1 1 1 K 1 1 1 1 1 r f , f 1 1 1 1 1 1 l 1 ` / ? 1 ? 1 ,1 + 1 1 I 1 4 1 1 1 1 1 1 + { 1 ! 1 , ! i I 1 1 l 1 1 ! r: , ! 1 1 1 ' f l / ?I I I 1 1 1 I 1 4 , ? , f 1 1 1 1 1 11 1 1 1 1 I S 1 I 1' • f 1 1 1 1 1 ' , A \1 1 1 , l 1 \?.a • 1 1 . f r 1 ? I I A 1 1 , 1 1 1 r r1 1 ' 1 1 1 1 1 1 1 1 I . ? I 1 1 1 1 1 1 , 1 1 1 r , { 1 1 1 1 , 1 r\ ; 1 . ; ! 1 1 ?• ' 1 1 ry1 1 ' 1 1 1 i 1 t r U O ._.•J u 2OQ i Z y 7 6V-= "GE SLOP= O 77::;=-' IN IN 1 (l ¦ . A.AA 1• U of 0 N .c ? L LL v E v of L v '> % ? rn u L \ rn • D q --to o Oo 40° °OoOad 0 °p 00 q o 0 o00 • v ? X00 ? in Cv O ° O 0? O q0 /• O a 1 ° O pa d a p0o : 0 q q '1 0 ° 00? ? 0 co cr L a} O r ?' :« C1 O \ / a) a? u> > «• O N 0 s1 a O O L- rn -v Lo - v a. v ?- N O ?'m_v(la rn Q.- C: c '- 4 0 ati C 0 m c o a ? ' 9 m ui z O -0 > , a N n ? w p? rP'.•O b- ? as ? a, E " ?o o Q) v o a. zizam 0 U LLJ m All. U _ a_ a N O c: u E E O ?- U as 41 iD 0.v Q. m 0 U) .0 Sri L ? v a CL U v .c .c N V) U a 3 ? a > r? ns 0- o w c Pry v] vi 0 L a Q) b E F-' ? D c (n O O L7 Q -0 w N 4) cv W k r "s r $ cn C ° o a "t3 ? ? c D C N a c lj z ¢ a 3 y, ? O?vC7 is ? ? a 0 cr a ' a o a . .c Ol --I r) U) J U z (L) N O L- V oZ C Cy, 0 cm of Q O Lt1 ' m °D o a o UZ z nQ ? g? LL, V) L I F L 0 Q 0 Q Z O i i s r I }F i s s 1 I w r } t' I 1 I I I ` .. -. C7 ELI O .. I z41 o In a F, a 1-7 i0 y _N I ?_ 1 u M !+) V co T _ # u !- Z Co ri ll -I W W? , o tiJ w a H a. = o N -? m ° a _ F- a q CL i W w U) In Y• C7 ti. D LL 7- W J O us vi °[ M a. Z U w D Z 2 0 Q ? W Q L ? (15 o w cc a ?" (:) w X z W "I ?- w U O a 3 a < Q a 0. a z +J 0 f- (L c? Ca w 4 Q ;e l_! L) U Z 00) bi W cc 11 CJ w i rom w CL a0 W 1lf u Q W a 4 L ? u a a a LX w V W (] a or r d J? r L o Fn r 4 N u /- W ?' a w z u m t C13 0 o s ..}}-- f r: r o F- w 4 Li a ~ a? x? f ( Z co to 1-1 C) co x w -G I -LO I I fY? a '? E c •? W Z X3 I a a • m U. ; F-- m Lo I ? ^ ' ? IA ? _ L_ _i v ? L?J I? = a V 1 ?- w U ri In 41 1 1 i Q W -1 W 4 a? u, H W C, W ? ?- a 1 z 0 U W cn ?z EL -n uj 21 10 C 'U 4J JI C) t t • ,r RR r` 1 0 O W N W a 0. s- 0 is L J f a U- OJ F" w r= J cn W ... N .W _Ln 11 W W J W x a -- r a c ?- : x -? ; ? 4 u? ? O .- k lAJ .r. i r.. x h .rN O O • ` ` O A C '? ON N i- -a 5 qtr _ a o' e_ f - O Q V D O °y W O M O C C J CL O 4 k1 Q V J a c r? r O? w ? p G r ? <L ? ! BE .°_ z Z a 4 s a n C r m W 0 1 V _ Ix N _ V a n M w = n a C 2 z v v " 3 w O a x w [J __- 3 0 ° i .n It Q w N a o N z N o u O - u o N i!1 C ,? u o a O - 'n o A ? - 4 W w W 41 b?v _ a E o C o ?L ° LL C) Z cr a n r u - H x a J O u) N J la ! - N - M v F- W ¦ ¦ N ? [J Z '• =t ° y m o = ? 1 W UI ?? Lu ua r z sS =3 NY 0 W o L o Z m U a 3 ? Wh o J d l O x= a ? z l ?Om n r O ? i 00? o . Z 1 ` q q U O , JN >n W Z I U) Y < O J u t J Li.. w J r i J ro G z W Q J C=i] a ?- W z no E-- J ? EY f S 7 3 f s f} ?i r D4 n • Q y? Q 4 a G Sn ? N 'b a Z b d W e; ?a pJ w o to u- a »- ? w a 3 w a a a z w J p u o LL co >- 4Z:ax w y w y a U Z-:.%.crG.m (D in -3u3$l7 Z4w- C3 w s u o F 6 4 b o ? f th h LL G R u a ? 6 o U ? w a C? a v t G C31 `- a ' c$ a Q ? O a W P u ? ti ° a ltJ o v , : V w .`'a IDo L U. x 1 = o_ x N ? - vx? ms's ? p fl' o Q P uT b D ? Z ? r fm Z ? Q p CD ls! s w - m O `r z n F? W (ni l e. e D q e • a O s., A .p p rn n4 v r+ cn in a a U n ? io ?i a C) zl-- \ CITY OF CLEARWATER DEPARTMENT OF PUBLIC WORKS STORM DRAINAGE DESIGN CRITERIA INTRODUCTION This manual is a guide to assist Engineers in the design of stormwater systems in the City of Clearwater. In general these standards are a combination of requirements set by the Southwest Florida Water Management District as administered by the Pinellas County Department of Environmental Management, and requirements set by the City of Clearwater, Public Works Department. This manual does not propose to itemize the requirements of the Southwest Florida Water Management District, but to highlight and detail the requirements of the City of Clearwater. Where design standards of applicable regulatory agency's. vary, the more restrictive or higher standard will apply. The Designer is required to be familiar with the current design requirements of the Southwest Florida Water ?.. Management District. The appropriate Southwest Florida Water Management District storm water permit and other applicable regulatory agency permits will be required prior to any final construction permit approval by the City of Clearwater. The Designers attention is called to the city of Clearwater requirement that all development and redevelopment will require provisions for storm water management. In particular, redevelopment will be required to provide storm water management facilities in accordance with the regulations herein. For the purpose of administering these stormwater management regulations, redevelopment is",'defined as the alteration of buildings, parking, or other landform features of a property which necessitates the land development code review process. Redevelopment of property for which no stormwater management facilities exists will be required to provide such facilities in accordance with the methodology contained herein, notwithstanding that the circumstances of the redevelopment may not result in an increase of stormwater runoff. -J