CITY OF TUCSON, ARIZONA DEPARTMENT OF TRANSPORTATION ENGINEERING DIVISION ACTIVE PRACTICES GUIDELINES

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1 CITY OF TUCSON, ARIZONA DEPARTMENT OF TRANSPORTATION ENGINEERING DIVISION ACTIVE PRACTICES GUIDELINES UPDATED 08/06/13 PREPARED BY: EFFECTIVE: --=08~-=06~-~13~-- APPROVED BY: DATE:_~0=8~-0=6~-1=3 _ SUBJECT: GREEN STREETS A. DEFINITIONS: 1. Basin: The area ftprint which identifies the ttal area f detained r retained runff. 2. Bttm f Basin: The flat area f the basin r the basin area minus the side slpes. 3. Green Infrastructure: Landscape and engineering features that utilize sils and vegetatin t manage strmwater fr multiple envirnmental and cmmunity benefits. These features, as described in Pima Cunty and City f Tucsn Guidance Manual fr Lw Impact Develpment and Green Infrastructure (in prcess), include but are nt limited t, curb scuppers, curb depressins, cre drills, water harvesting basins, swales, bi-retentin basins, berms, check dams, infiltratin trenches, and active water harvesting/strage systems. 4. Green Streets: Radways that incrprate the use f Green Infrastructure. 5. Mature Tree Canpy: The estimated diameter f leafy vegetatin f a given tree. 6. Prject Manager: The City f Tucsn, Department f Transprtatin individual wh is appinted t versee the prject. 7. Shrub, Grass and Grundcver Requirement: A minimum 25% recmmended vegetative cverage f the bttm f basin area. 8. Tree Canpy Area: The area that can be planted with trees withut sight visibility r utility cnflicts. The shade fr each tree shall be calculated at an average f 18' mature diameter in rder t prvide the recmmended minimum 25% cverage f the tree shade area. B. INTENT: The intent f these guidelines is t require the incrpratin f green infrastructure features int Tucsn radways wherever pssible. The csts and benefits f green infrastructure shall be evaluated and determined fr all new prjects and shall be included within the prject budget. 1 Exhibit A t Reslutin 22116

2 C. APPLICABll.JTY: These guidelines apply t new cnstructin and recnstructin (including widening, realignment, etc.) f publicly funded radways r drainage prjects including neighbrhd radways, drainage r Strmwater management prjects, within the City f Tucsn that include a landscaping element. These guidelines shall nt apply t radway maintenance prjects such as pavement preservatin, resurfacing r landscape and irrigatin maintenance. D. GREEN STREET PERFORMANCE GOALS: These guidelines create the fllwing perfrmance GOALS fr radways within the City f Tucsn wherever pssible: Strmwater runff frm the radway shuld be directed thrugh green infrastructure features in parkways and medians befre entering strm drains r natural drainage ways. Green infrastructure features shuld encurage maximum dispersal and infiltratin f strmwater acrss the pervius area f the prject. Landscape areas are designed t retain at least the first W' f rainfall falling n the radway and public right-f-way (nt including run-n frm ther streets and prperties). In areas where the W' gal cannt be met due t site cnstraints, green infrastructure features shuld be incrprated int as much f the landscaped area as pssible. The vlume shall be calculated as the "Prject Site Area x 12." Green infrastructure basins are designed t accept a maximum final pling depth f eight inches f strm water. All green infrastructure basins must drain within 24 hurs f the latest rain event. In areas withut adequate infiltratin rates t meet this gal, strmwater shuld be ruted thrugh vegetated areas befre discharge t strm drains. Strm water runff is directed t prvide supplemental irrigatin t the landscape. Landscape planting criteria shall generally be as fllws: The bttm f basins are planted with a minimum 25% cver f grundcvers, bunch grasses, and/r shrubs less than 3' in height. Mature tree canpy cvers a minimum f 25% f the Tree Canpy Area. Within five years f planting, the vegetatin survives n harvested rainwater, r with infrequent supplemental irrigatin. E. REQUIREMENTS: Trees are lcated t prvide shade n sidewalks. All basin planting areas shall be ripped t a minimum depth f 12" prir t planting. All prjects meeting the APPLICABILITY (C.) definitin shall be cnsidered t be Green Street prjects. The Perfrmance Gals can be met in a variety f ways. All reasnable effrts shuld be made t meet r exceed these gals. 2

3 TDOT shall develp a permanent prject review team t include planning, engineering, landscape, and the design/cnstructin prject manager. This team shall review the prject dcuments at each stage including Early Planning, Design Cncept Reprt (DCR), Design Cnsultant scpe f wrk, 30%, 60%, 75%, 90%, 100% plans, and Cnstructin t determine if the APG intent has been met. The Landscape Architect shall review the as-builts, t determine that the intent has been met. Design: During the creatin f the DCR and/r 30% plans, the cnsultants and the TDOT prject review team shall agree n a set f Perfrmance Gals apprpriate t the prject. In the event that these gals are less stringent than thse utlined in the APG, the Directr f Transprtatin shall be apprised by Memrandum utlining reasns why the gals cannt be met. Cnstructin: If at any stage in the cnstructin prcess a mdificatin t the prpsed design is determined t be necessary, plans fr the mdificatins shall be reviewed by the Prject Manager, wh will ntify the reviewers f the changes prpsed and the impacts t the riginal Perfrmance Gals established during the design. The reviewers shall review and ffer input as t pssible alternatives t be used t meet the riginal standard. A reprt shall be made by the Prject Manager and submitted t the Engineering Administratr describing each prject's green infrastructure, the cst, and ability t achieve cmpliance. F. PRINCIPLES: The design cm:ept and intent fr green infrastructure is t retain, detain, infiltrate, and/r filter runff frm the street and sidewalk in landscaped areas behind existing r prpsed curbs (parkways and medians). Water is retained r detained in depressins (basins, swales) r back f munding (berms). This runff is t be used fr supplemental watering f plant materials within the public right-f-way. Where runff exceeds retentin and infiltratin capacity, it shuld be slwed, spread, and/r filtered thrugh vegetatin t remve debris and sediment frm the water befre it returns t natural watercurses. Civil and landscape design shall include infrastructure t meet the intent f this prcess and incrprate materials, grading, and amenities t be cmpatible with bth this effrt and the prject functins fr street, drainage, pedestrian, and landscape. G. GREEN INFRASTRUCTURE PLANNING: The purpse f the APG shall be met thrugh the implementatin f Green Infrastructure Planning fr qualifying radway prjects. The Green Infrastructure Planning prcedure shall fllw this prcess: 1) The design cntract scpe f wrk shall indicate an bjective t integrate and maximize green infrastructure pprtunities in the areas t be landscaped: a) The COT Prject Manager shall receive input frm the civil and landscape designers identifying the lcatins f ptential green infrastructure pprtunities. The intent is that drainage planning, grading and landscaping will be planned in an integrated fashin. 3

4 b) The Design Cnsultants shall be required t crdinate with utility cmpanies n determining utility lcatins during the early design stages t identify ptential pprtunities. c) The Prject Manager shall review all submittals t be sure that the APG intent is met. The Prject Manager shall slicit the help f staff engineers and landscape architects t review all pertinent cntract dcuments t ensure this plicy is fllwed. 2) At the 30% submittal/design cncept reprt, the Cnsultants shall include: a) Series f figures indicating the green infrastructure methds that are prpsed alng the radway b) Cnceptual radway crss-sectins that demnstrate: i) Optimal grading f radway surfaces t direct runff int adjacent landscape areas ii) Placement f trees and vegetatin t maximize shading and water quality imprvement iii) Placement f curb pening/flush curb and catch-basin cnceptual details. c) Utility plan, created in crdinatin with utility cmpany representatives, that includes: i) Plan view map f preferred lcatins (including jint trenching where apprpriate) fr undergrund and abvegrund utilities t minimize cnflicts with streetscape and basins. ii) Indicatin f each affected utility' s cmpatibility f existing utilities with ptential green infrastructure areas. d) Plan view and Landscape Plans fr radway that demnstrate: i) Cnceptual type f green infrastructure features ii) Cnceptual details fr water ingress t and egress frm basin areas (such as scuppers, curb penings, flush curbs, and verflws) iii) Landscape cncept shwing placement and type f vegetatin t maximize utilizatin f strmwater runff and prvide shade.. 3) At the 60% submittal, the Cnsultants shall include: a) Preliminary sectins indicating extent and depth f retentin areas, slpes, and areas f strmwater flw and verflw b) Preliminary planting plan, indicating specifically hw plants are utilized within and arund basins c) A defined utility crridr fr ptential mdificatins d) Irrigatin plan utlining types r methds f watering such as Dri water, temprary systems used fr establishment nly, quick cupler and cnversin t lng term systems. 4) The Prject Manager shall enlist the help f civil engineer and landscape architect reviewers t determine the feasibility f prceeding as prpsed and t mdify green infrastructure features as needed t meet the prject budget. 5) At the 75% and 90% plan submittal, the Cnsultant shall prvide cnstructin dcuments. Said dcuments shuld be detailed and explanatry enugh t allw cntractrs t build. The Prject Manager shall review t make sure all incrprated cmments have been addressed with the help f the review team. 4

5 6) At the 90% submittal the Landscape Cnsultant shall prvide: a) Calculatins n the detail sheets dcumenting the fllwing: i) Y2'' rain vlume fr the ttal prject site ii) Ttal retentin (final pling) vlume f green infrastructure features within the prject area iii) Estimated vlume f water t be retained by green infrastructure features annually iv) Annual irrigatin requirements fr the prpsed planting plan at maturity b) Estimated water and maintenance cst based upn a scpe described in the design cntract. 7) At the 100% stage, the utility cmpanies shall be ntified f the upcming cnstructin and its prpsed start date. Utility cnflicts will be addressed by each utility cmpany at this time, thrugh final design and cnstructin, making use f the utility crridr prvided n the plans, where pssible. 8) The Prject Manager, Landscape Architect and the Prject Inspectr team shall meet t review the green infrastructure elements prir t the pre-bid meeting. The team shall identify and review the element with the General Cntractr at the pre-cnstructin meeting and during the weekly cnstructin meetings as needed t ensure the crrect installatin and develpment. 9) The Landscape Architect shall mnitr the maintenance f the green infrastructure elements during the tw-year Landscape Establishment perid. 10) The Landscape Architect shall review the green infrastructure elements with the Streets Maintenance Sectin prir t turn ver and final acceptance. 5