As part of my work as a consumer advocate, for over four years now I’ve been active in the water sector chairing a Customer Challenge Group for South East Water. So I’ve been attending lots of discussions and events about water and trying to keep up with all the acronyms and terminology in the sector.<\/p>\n
I was thrown when I first heard references to blue, green and grey water. What on earth is this all about, I thought – and you might too.<\/p>\n
The blue \u200bwater refers to \u200bfreshwater. \u200b<\/p>\n
The green \u200bwater refers to \u200bwater stored in \u200bsoil.<\/p>\n
The grey \u200bwater is \u200bpolluted water. \u200b<\/p>\n
I understand that globally \u200bthere is enough \u200bfreshwater on \u200bour planet to \u200bsupport \u200beven 10 billion \u200bpeople \u200b(not if we all \u200blive like in \u200bthe USA), \u200bbut grey \u200bwater can dangerously pollute \u200bblue and green \u200bwater.<\/p>\n
In an online discussion of the different types of water, I found this analysis:<\/p>\n
“Rain fed \u200bagriculture \u200bcovers 80% of \u200bthe world’s \u200bcultivated land,\u200b and is \u200bresponsible for \u200babout 60% of \u200bcrop production.\u200b In rain fed \u200bagriculture the \u200bsoil stores the \u200brain and \u200breleases it \u200bslowly to the \u200bplants. This \u200brainwater used \u200bin agriculture \u200bis part of what \u200bis called ‘\u200bgreen \u200bwater\u2019 \u200band is a \u200bcharacteristic \u200bof the land on \u200bwhich it falls. \u200bIt is usually \u200bnot subject to \u200bcompetition \u200bfrom other \u200bsectors. \u200b<\/p>\n
Yields in \u200brain fed \u200bagriculture are \u200bstill far from \u200btheir potential.\u200b In 2005, \u200bcereal yields \u200bwere about 1.1.\u200b5 tonnes per \u200bhectare in Sub-\u200bSaharan Africa, \u200bcompared with 5 \u200btonnes per \u200bhectare in \u200bEurope. \u2018\u200bGreen \u200bwater\u2019 or \u200brain fed \u200bagriculture has \u200ban important \u200brole to play in \u200bsustaining \u200bpopulations and \u200bsecuring future \u200bfood supplies.<\/p>\n
By contrast, \u200bin irrigation, \u200bwater is \u200bextracted from \u200brivers, lakes \u200band aquifers (\u200bwhich is \u200breferred to as \u200b\u2018blue \u200bwater’). \u200bThis \u2018\u200bblue water\u2019\u200b is applied on \u200bland, where \u200bmost of is \u200bconsumed by \u200bevapo \u200btransportation. \u200bIrrigation \u200bcompetes with \u200bother sectors (including the \u200benvironment) \u200bfor \u2018blue \u200bwater.\u2019 \u200bToday irrigated \u200bagriculture \u200bcovers about 20%\u200b of cultivated \u200bland and \u200baccounts for 40%\u200b of global food \u200bproduction. \u200b’Grey \u200bwater’ is \u200bpolluted or \u200bwaste water, \u200bwhich can be \u200brecycled and \u200bpurified. Grey \u200bwater will play \u200ban important \u200brole in \u200bsecuring future \u200bglobal water \u200bsupplies.”<\/p><\/blockquote>\n
So, now you know …\u200b<\/p>\n","protected":false},"excerpt":{"rendered":"
As part of my work as a consumer advocate, for over four years now I’ve been active in the water sector chairing a Customer Challenge Group for South East Water. So I’ve been attending lots of discussions and events about water and trying to keep up with all the acronyms and terminology in the sector. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-19997","post","type-post","status-publish","format-standard","hentry","category-environment"],"_links":{"self":[{"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=\/wp\/v2\/posts\/19997","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=19997"}],"version-history":[{"count":4,"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=\/wp\/v2\/posts\/19997\/revisions"}],"predecessor-version":[{"id":20001,"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=\/wp\/v2\/posts\/19997\/revisions\/20001"}],"wp:attachment":[{"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=19997"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=19997"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.rogerdarlington.me.uk\/nighthawk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=19997"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}