Municipal Class Environmental Assessment (EA) Study for the Stormwater Servicing and Tributary Works for the North Lambeth No.

Transcription

1 Municipal Class Envirnmental Assessment (EA) Study fr the Strmwater Servicing and Tributary Wrks fr the Nrth Lambeth N. P-9 SWM Facility The purpse f this PIC is t present: a descriptin f the Class EA prcess; a summary f the existing cnditins; a summary f the prblems and pprtunities; a descriptin f the alternative slutins cnsidered (i.e. d nthing); evaluatin f alternatives including criteria and methdlgy; a descriptin f the preliminary recmmendatins; and a summary f the future activities t be cmpleted.

2 Yur cmments are imprtant t us. Fllwing yur review f the infrmatin, please cmplete ne f the cmment frms and place it in the bx prvided r send it back t the address n the frm prir t Nvember 28, If yu have any questins ur representatives will be pleased t assist yu. Nelsn Oliveira, P.Eng. Prject Manager Nick Emery, P.Eng. Water Resurces Engineer Crri Marr, H.B.Sc. Senir Planner David Gugh, P.Eng. Envirnment Service Engineer Sctt Mathers Manager, Strmwater Management Divisin

3 The Class EA prcess is a five phase planning prcess which: This study will : identifies reasnable slutins t the Prblem; cnsiders advantages and disadvantages including net envirnmental effects; requires public cnsultatin; and prvides clear dcumentatin that describes the decisin making prcess. Fllw the Schedule B Class EA requirements. Cmplete Phases 1 & 2. Dcument the decisin making prcess in a Screening Reprt t be filed fr a 30 calendar day review perid. Schedule B Prjects Schedule A Prjects Schedule A+ Prjects Schedule C Prjects Typical r Emergency Operatinal Infrastructure Prjects Typical Infrastructure Prjects Phase 1 Prblem r Opprtunity Phase 2 Alternative Slutins Phase 3 Alternative Design Cncepts fr Preferred Slutin Phase 4 Envirnmental Study Reprt Phase 5 Implementatin Pre-apprved Prceed t Cnstructin Pre-apprved Ntify Public Prir t Implementatin Identify & Describe the Prblem/Opprtunity Prepare Envirnmental Inventry, Identify/Evaluate Alternative Slutins & Establish the Preferred Slutin Prepare and file Prject File Evaluate Alternative Design Cncept, Identify Envirnmental Effects Mitigatin & Preferred Cncept Prepare and File Envirnmental Study Reprt (ESR) Dcumenting Phases 1-3 fr Public Review Prject Cnstructed / Restre Disturbed Areas

4 Cnfirm all drainage/catchment and sub-catchment areas; Identify a drainage cnveyance system fr the prpsed Nrth Lambeth N. P-9 SWM Facility; Identify any necessary dwnstream channel mdificatin wrks; Evaluate the benefits f incrprating Private Permanent Systems (PPS) int the preferred strmwater servicing strategy; Prvide a preliminary design fr the preferred slutin and develp crrespnding cst estimates; Preserve dwnstream channel baseflw; Mitigate the pssibility f dwnstream channel ersin caused by the runff frm future grwth; Prevent any increase in future fld risk ptential; Prtect surface water quality; Maintain an apprpriate diversity f aquatic and terrestrial life; and Prvide pprtunities fr human uses.

5 As a result f nging urban develpment within the study area, a cmprehensive strmwater servicing strategy must be develped. The intent f the Servicing Strategy is t: Mitigate negative impacts f grwth n water quality/quantity, as well as flding and ersin; Identify required infrastructure; Reduce negative impacts n landwners and the envirnment; Prvide a cst-effective slutin. Ultimately, the Servicing Strategy and strmwater management measures will IMPROVE eclgical functin and result in the greatest envirnmental benefit.

6 Schedule A f the City f Lndn Official Plan identifies land use designatins fr the study area as lw & medium density residential and pen space. Schedule B1 identifies the natural heritage features f the area. This includes areas f unevaluated vegetatin patches and significant crridrs alng the creek. Schedule B2 indentifies natural resurces and hazards fr the area and identifies the study area as being within the Upper Thames River Cnservatin Authrity regulatin limit and within the regulatry fldline.

7 Clnel Talbt Rad Bx Culvert Frest City Cmmunity Church: Run-ff cntrlled by existing n-site SWM pnd Tributary C Anguish Drain (Open) Anguish Drain (Clsed)

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10 DP-1a -(Dwnstream) Channel transitins frm manicured lawn t a naturally vegetated area dwnstream f private prperty. Flw is split int tw small, shallw flw paths heavily cntrlled by dense vegetatin. Numerus flw paths within the brader valley becme active during high flws as the watercurse appraches its cnfluence with Dingman Creek, resulting frm the dense shrub vegetatin and minr variatins in lcal tpgraphy. DP-1b - Based n bservatins made frm Clnel Talbt Rad, the channel becmes well-defined and displays a mre natural frm. Evidence f widening as bank ersin was typically bserved and installed stne prtectin was being ut flanked. Signs f verbank flw were bserved with depsitin nted n the fldplain at the dwnstream reach limits. DP-2 - This reach is gemrphlgically sensitive transitining frm hardened banks t less resistant, natural bank materials. A scur pl has frmed immediately dwnstream f the transitin pint as flws are sediment starved. Scured material is depsited further dwnstream frming depsitinal features as the channels carrying capacity is re-established. A mre natural channel frm is established in the upstream prtin f this reach. Ersin and slumping exists alng the Clnel Talbt Rad embankment as it acts t direct flws twards the dwnstream culvert crssing. The Clnel Talbt Rad culvert appears t be large enugh t cnvey flws, but des nt prvide sufficient space fr natural channel migratin t ccur. Reach Breaks Watercurse Ill-Defined Channel DP 3 Channel has been mdified, straightened and lined with rip rap, as it flws adjacent t numerus residential prperties Due t the stne lining, the channel is mre r less gemrphlgically stable with evidence f verbank flw nted DP 4 Demnstrated mre defined channel frm, with an irregular meandering planfrm Signs f verbank flw were evident via brushed grasses and siltatin ver fldplain vegetatin The small mre defined channel cnveys lw flws while higher flws are cnveyed within the brad, vegetated valley fldplain which als prvides prlnged water strage DP 5 (Upstream) is a lw-lying, intermittent (semi-dry) drainage channel lcated within an agricultural area. The channel is prly-defined, with diffuse flw ccurring ver the flat fldplain.

11 Scial/Cultural archelgical and cultural heritage public health and safety prperty impacts/acquisitin aesthetics land use (e.g. meets Official Plan bjectives and is cnsistent with the existing Draft Plan) abriginal/first natins lands, treaty rights cmpliance with applicable studies/reprts Natural Envirnment fldplain impact/ plicy ersin and sedimentatin in dwnstream tributary aquatic habitats terrestrial habitats migratry/ther birds: (e.g. waterfwl, sngbirds) special habitat areas (specially designated r prtected habitats, migratin rutes, specific plicies) grundwater quality and quantity Recmmended Slutin Technical achieves strmwater design targets develped based n the Draft 2014 Dingman Creek Subwatershed Study Update cmpliance with applicable design standards cmpliance with OMB Decisin dated February, 2014 regarding Auburn lands and servicing cmpliance with applicable watercurse and fldplain plicies (Official Plan, UTRCA guidelines) site design and peratinal challenges getechnical cnsideratins that may affect implementatin f strm drainage measures risk and cnsequence f system failure Ecnmic initial capital cst prperty acquisitin csts peratin and maintenance csts cmpliance with Develpment Charges Backgrund Reprt

12 Optin A: SWAP SWM Pnd Lcatin Optin B: Pnd in area withheld frm OMB Decisin Optin C: SWAP & OMB SWM Pnd Lcatin

13 Alternative Descriptin Preliminary Evaluatin D Nthing Imprvements r changes t existing strm drainage and strmwater management (SWM) measures wuld nt be implemented in the study area t service future grwth. This slutin des nt address the prblem. It des nt cmply with the Official Plan Plicies r the Prvincial Plicy Statement specific t the prvisins t ensure necessary infrastructure will be available t meet current and prjected grwth. It des nt cmply with regulatry requirements r prtect human health and the natural envirnment. Carried Frward fr Further Cnsideratin Limit Grwth Residential grwth wuld be limited within the study area. This slutin des nt address the prblem. It des nt cmply with the Official Plan Plicies r the Ontari Municipal Bard decisin permitting grwth within the study area. Lw Impact Develpment (LID) Permanent Private SWM Measures (PPS) LID is a series f cst-effective, lt-level strategies that try t replicate predevelpment cnditins and generate less runff by infiltrating rainfall int grundwater, evaprating rainwater back int the atmsphere after a strm, and finding beneficial uses fr water rather than cnveying it thrugh strm sewers. PPS are intended t be used in medium and high density residential; (MDR/HDR) institutinal ; cmmercial and industrial develpments (ICI). These systems may include depressed strage in parking lts, green rf strage, and il and grit separatrs. This slutin des nt prvide sufficient capacity t treat runff n its wn and meet the quality and quantity cntrl targets as utlined in the Dingman Creek Subwatershed Study (DCSS). This slutin may supplement end-f-pipe cntrls. Permanent Private SWM measures may be beneficial t address water quality and quantity in MDR and ICI land use designatins but given that the MDR land use frms a relatively small percentage f the develpment area, benefits may nt be significant if implemented n their wn. PPS may supplement end-f-pipe cntrls. End-f-Pipe Alternatives Typically multi-purpse strmwater management facilities addressing bjectives relating t water quality, ersin cntrl, and peak flw cntrl. Dry pnds, wet pnds, and wetlands are typical alternatives, althugh dry pnds are nt cnsidered a feasible alternative fr this applicatin. This slutin des address the prblem. It cmplies with the Official Plan Plicies, Prvincial Plicy Statement and OMB decisin specific t the prvisins t ensure necessary infrastructure will be available t meet current and prjected grwth. End f pipe facilities can be designed efficiently, prvide water quality and quantity cntrl t meet DCSS targets, and can service drainage areas > 10 hectares.

14 This slutin prvides strm cnveyance and SWM measures fr an apprximately 119 hectare area triggered by develpment. A Reginal SWM Facility designed as a wet pnd will prvide water quality, quantity, and ersin cntrl fr 115 hectares. Runff frm the remaining service area will be treated by n-site SWM cntrls that will discharge t external drainage wrks lcated in the Clnel Talbt Rad right-f-way. The SWM measures will prvide MOE Enhanced Prtectin Level water quality cntrl, as described in the MOE design guidelines. Outlet imprvements will be required t cnvey strmwater frm the prpsed SWM facility t the existing dwnstream channel. Pipe r pen channel culd be used fr this purpse, an pen channel prvides ptential benefits including natural heritage mitigatin, passive recreatin, and habitat creatin. The prpsed utlet imprvements will be identified in further detail fllwing cnfirmatin f the preferred slutin.

15 Summer 2014 Fall 2014 Ntice f Prject Cmmencement issued July 24 th and August 21 st, 2014 Prject Team Meetings Class EA Phase 1 Agency/Stakehlder Cnsultatin Class EA Phase 2 Ntice f PIC issued Octber 30 th, Nvember 6 th, 2014 PI C #1 Nvember 12, 2014 Distributin f : Letter Newspaper Ntice City f Lndn website Prject Team meets regularly thrughut the study Includes City persnnel and cnsultants Review existing cnditins Identify the Prblem Cnfirm the need and justificatin Identify slutins UTRCA MNR MOE CNR AANDC/MAA Develp evaluatin criteria and methdlgy Identify impacts Identify mitigatin measures Identify preliminary recmmendatins Distributin f : Letter Newspaper Ntice City f Lndn website Present evaluatin criteria & methdlgy Alternative slutins Preliminary recmmended Alternative Winter 2015 Receive and Address Cmments frm PIC Draft Recmmendatins t the City Municipal Class Envirnmental Assessment Study fr the Nrth Lambeth N. P-9 SWM Facility City Cuncil Endrsement Ntice f Prject Cmpletin 30 Day Review Perid Detailed Design and Implementatin Indicates where we are in the prcess. Dcument Class EA prcess, alternatives and recmmendatins Distributin f : Letter Newspaper Ntice City f Lndn website File Class EA dcumentatin fr mandatry 30 day review perid If n Part II rders, prceed t detailed design and implementatin

16 Fall 2014/ Winter 2015 Receive / cnsider input frm public and agency cnsultatin t cnfirm r refine the preliminary recmmended slutin; Stantec t identify mitigatin measures t reduce/ffset ptential adverse effects; Receive cuncil endrsement f recmmended slutin; Prepare Screening Reprt. Winter 2015 Issue a Ntice f Cmpletin and File the Screening Reprt fr the mandatry 30 day review perid; Address cmments raised during the 30 day review perid; Anyne with utstanding cncerns, which cannt be addressed, may, within 30 calendar days f the Ntice f Cmpletin, request the Minister f Envirnment t issue an rder t cmply with Part II f the EA Act, knwn as a Part II Order, bumping up the status f the prject; If n Part II Order requests are received, then the City may prceed with design & implementatin. Spring 2015 Detailed Design and Cnstructin