Environmental Engineering Reference
In-Depth Information
had.a.pronounced.effect.on.the.whole-life.cost.for.most.BMP.facilities..For.
instance,. the. level. of. maintenance. for. retention. ponds. and. wetlands. had. a.
much. greater. inluence. on. whole-life. cost. than. construction. cost..Also,. the.
model.developed.by.the.Water.Environment.Research.Foundation.(WERF).
study.predicted.that.small.sites.with.a.high.level.of.maintenance.would.have.
a.greater.whole-life.cost.compared.with.facilities.that.were.10.times.as.large,.
but.maintained.at.low.or.medium.levels..The.costs.of.developing.or.retroit-
ting,.operating,.and.maintaining.a.drainage.system.are.normally.lower.for.
BMPs.than.for.a.traditional.system,.but.the.high.land-take.required.by.wet-
lands.is.a.major.cost.factor.in.their.selection.
StormwaterReuse
Stormwater.can.be.used.for.aquifer.and.groundwater.recharge.and.reused.
for.non-potable.use.in.homes,.for.example,.garden.watering,.toilet.lushing,.
hot. water. supply,. and. car. washing,. and. for. commercial/industrial. use. in.
cooling. towers,. cleaning. processes,. and. electricity. generation.. The. beneits.
of. stormwater. reuse. include. freeing-up. capacity. within. sewerage. systems,.
thus.facilitating.further.development;.decreased.volumes.of.treated.efluent.
lows.to.receiving.waters;.reducing.water.bills.for.the.community;.and.in.less.
economically. developed. countries,. reducing. the. incidence. of. water-related.
diseases.as.reused.stormwater.is.usually.of.better.quality.than.water.from.
traditional.sources.
Rousseau.et.al.. (2008).note.that.large-scale.applications.of.water.reuse.of.
efluent. from. constructed. wetlands. are. widespread. in. Australia. and. the.
United.States.but.less.common.in.Europe..Australia.uses.320.L.of.water.per.
capita. per. day. for. domestic. purposes,. and. its. cities. will. have. a. predicted.
15%.average.decrease.in.rainfall.by.2030..A.signiicant.volume.of.rainwater.
in.Australia.becomes.stormwater.run-off,.and.in.Sydney,.it.is.estimated.that.
420.GL.of.stormwater.is.discharged.into.the.sea.every.year..The.Metropolitan.
Adelaide.stormwater.reuse.project.(Australia.Government.Department.of.the.
Environment,.Water,.Heritage.and.the.Arts,.2009).uses.constructed.wetlands.
to. pretreat. stormwater. before. pumping. it. through. bores. to. underground.
water. supplies. beneath. the. city.. It. will. save. 1000.ML. of. water. per. year. by.
using.stormwater.to.replace.water.drawn.from.underground.supplies.for.the.
irrigation.of.parks.and.gardens..In.Northern.Adelaide,.the.City.of.Playford's.
parks. and. reserves.will.be.irrigated.by.570.million.liters.of.water.per.year.
from.4.ha.of.constructed.wetlands.(Australian.Academy.of.Science,.2008).
In. general,. stormwater. BMPs. can. potentially. offer. improved. safety. over.
conventional.drainage.systems,.given.the.reduced.presence.of.gully.pots.and.
drain.covers,.while.the.total.separation.of.surface.drainage.systems.means.
fewer. routes. for. vermin. to. enter. piped. systems.. In. addition,. the. reduction.
Search WWH ::
Custom Search