1. Ecological Retrofittingon AlgonquinCollege Campus
Beach closuresare orderedineventswherethe watertestedatthe beachhas a highlevel of E.coli(>100
CFU/100 mL)1
. Thisisnot onlya nuisance topatrons seekingameanstocool off in the Ottawa river,but
inadditionimpactsecological biodiversity,andcancause healtheffectsassociatedwithbathing/drinking
contaminatedwater. The Westborobeachlocationisupcurrentof the 18 CSO locations1
alongthe
Ottawariver,but there are othersourcesof contaminationinthe Pinecrest subwatershed. The
Pinecrestcreekisanurban creekthatemptiesintothe Ottawariverjustupcurrent onthe Westboro
Beach2
.
AlgonquinCollegeislocatedinside the Pinecrestsubwatershed2
,andsoasa large institution,itis
importantforAlgonquintotake measurestoreduce itsenvironmentalimpact. Algonquincollege should
focuson waysto reduce waste waterproductionaswell asdecrease stormwaterrunoff3
.
RetrofitOptions to Decrease Wastewater(recommendingimplementingone ormore of these options):
Low flowtoilets
Urine divertingtoilets
Automaticfaucets
Vacuumtoilets
As the Cityof Ottawa worksto separate the wastewaterpipesfromthe stormwaterpipes,combined
sewage overflows(CSO’s) will continue tobe anissue followinglarge precipitationevents. Eliminating
the CSO’s,althoughalreadyunderway,isaveryexpensive andtime consumingproject. Everysewer
overflowhasconsequencestothe healthof the ecosystemandanyusersof the contaminatedwater;it
isessential toact fastto decrease the CSO’s. Inthe meantime,projectstoreduce the volume of
wastewaterwill helptodecrease the CSOvolume enteringthe rivers,andthiswillhelptoreduce the
2. beachclosuresat WestboroBeach. The above bulletedlistsummarizesthe watersavingideas,andI
recommendimplementingone ormore of these ideasintothe AlgonquinCollegecampus.
Low flowtoiletscansave onaverage aboutone litre of waterperuse. Savinga litre peruse wouldhelp
overall,howeversome of the otheroptionsmaysave more waterperuse. Urine divertingtoiletsare a
great wayto save on waterbecause the fluidvolumefromeachuse isdivertedawayfromthe waste
water,and the nitrogenousproductcanbe usedas a fertilizer. The urine divertingtoilethasalot of
potential tosave onwaterbecause people tendtoexcrete urinemore frequentlythanfeces.
Automaticfaucetsare useful forpublichealth,butalsoconservewaterthatwouldotherwise be wasted
by people whoforgettoshutthe tap off. Upgradingmanual faucetsoncampus wouldalsobe an
excellentopportunitytocheckfortap leaks(andfix anytap leaks). Thisisa goodwayto save
wastewatervolume,howeverthe toiletswouldbe mypriorityforretrofittingbecausetoiletsconsume
more water.
My final retrofittingoptiontoconserve waste watervolumeoncampusisthe vacuumtoiletoption;this
optionpotentiallysavesthe mostwater(usesupto1.5 L, versusstandardtoiletswhichuse 6-8 L). Less
wateris requiredperflushbecausethe powerof the vacuumcarriesthe waste away4
. Waste products
may evenbe senttoan alternate facilityforbiogasproduction. Sendingthe waste producttoa biogas
plantwouldsave onwaste watervolume andwouldreduce our burdenonthe watertreatmentplant.
For ultimate watersavings,the vacuumtoiletcanbe usedinconjunctionwithaurine divertingdevice4
.
RetrofitOptions to Decrease Storm WaterRunoff (recommendimplementing all followingoptions,as
well asexpansionof the rooftopgarden):
Rooftopgardens
Raingardens
Permeable pavement
3. Retentionpond
Algonquincollege alreadyhasalivingwall,andarooftopgarden. It looksbeautiful,anditalsofunctions
to save storm waterrunoff volume. Applyingthe rooftopgardenapproachtoall buildingsoncampus
wouldbe a great wayto convertthose impervioussurfacestoslightlymore pervious- nottomentionthe
aestheticappeal. Inthe same theme asrooftopgardens,raingardensonthe groundlevelsave waterin
the same way: uptake bythe plants,andeventuallyevapotranspiration3
. Plantsactto decrease the
volume of stormwater,as well asutilize the nutrients,whichotherwisewouldbenefitthe harmful
bacteriaassociatedwiththe WestboroBeachclosures. Increase inplantlifeonthe campusresultsina
decrease of stormwaterrunoff volume;whichdecreasesthe opportunityof stormwatercarrying
harmful bacteriaintothe rivers3
.
Permeable pavementisagreat wayto reduce the storm waterrunoff volume,andIhighlyrecommend
thisoption3
. Figure 1 showsthe campus outlinedinblue;the campusconsistsmostlyof impervious
ground. Switching all the pavedsurfacestopermeablepavementwouldallow the would-be storm
waterrunoff to infiltrate intothe groundwater. Stormwaterpassingoverpavementisaliabilitytothe
nearbystreamsandriversbecause the stormwatercarries the contaminantsdirectlytothe basin,often
withoutmeansof purification. While waitingtoimplementthe permeablepavementoptionintothe
campus,buildingaretentionpondwouldbe agreat wayto mitigate the stormwaterprobleminthe
meantime. The retentionpondwouldbe relativelyeasytoinstall,andcouldpotentiallyincrease
biodiversityoncampusrightaway!The retentionpondoptionnotonlydivertsstormwaterrunoff away
fromthe stormsewers,butitalsofunctionstocleanse the waterinthe natural way (settlingand
biological uptake of nutrients)3
.
4. ConcludingRemarks:
The City of Ottawaputs out a 24 hour noswimadvisoryinthe eventof 5 mm of precipitation ormore
for the WestboroBeachlocation. Large precipitationeventsare predictorsof CSO’s,andstormwater
runoff alsocarriescontaminantstothe basin. The Cityof Ottawa isworkingtoseparate the combined
sewersystemtopreventfuture CSO’s,butitisa slow process,andinthe meantime,the healthof the
ecosystemandthe residentsare at stake. Withthe intensityandfrequencyof stormsexpectedto
increase asthe climate continuestochange,the CSOproblemisexpectedtogetworse before all the
necessaryupgradestake place.
For now,itis up to residentsandlocal institutionstobe mindful of waterconsumption. Algonquin
College ispreparingtoinvestinlowimpactdevelopmentandretrofittingoptionstoreduce waste water
outputas well asdecreasingstormwaterrunoff oncampus. The combinationof reducedwaste water
and stormwaterrunoff will resultinlowervolumesof contaminatedwater3
enteringthe Ottawariver,
and reduce ourburdenon the watertreatmentfacility.
My ideasforretrofittingoptionsandlow impactdevelopmentprojectsoncampusare: low flow toilets,
urine divertingtoilets,automaticfaucets,vacuumtoilets,raingardens,rooftopgardens,permeable
pavement,andretentionpond. Irecommendimplementingatleastone (ormore) retrofittingoptions
to reduce waste water,andmy toppick isthe vacuum toilet option4
. Asforthe storm waterrunoff
problem,the more optionsthatare implementedthe better3
. The permeablepavementoptionis
expectedtohave the largesteffectondecreasingstormwaterrunoff,butthe otheroptionswill helpas
well,andcould alsobecome community/studentengagementtype projects.
