A DAM SIGHT BET­TER

Heavy rain brings re­lief but lots more needed

The Star Late Edition - - NEWS - ILANIT CHERNICK ilanit.chernick@inl.co.za @Lanc_02

THE DARK, heavy clouds gath­ered while the group stood on the Vaal Dam wall as a light driz­zle be­gan to fall.

On prior vis­its to the Vaal Dam, in Au­gust and Novem­ber last year, The Star wit­nessed the clear skies with no rain in si­ight as the sun beat down on the dry­ing riverbed.

Be­tween Jan­uary and Novem­ber last year, the Vaal Dam was drop­ping at an ex­treme rate. At the time, the con­sult­ing of­fi­cer for the Depart­ment of Wa­ter and San­i­ta­tion (DWS) at the Vaal, Pi­eter Ver­maak, said they were los­ing about 10cm a day, which was a sig­nif­i­cant amount.

At the end of Au­gust the Vaal was on 33.7 per­cent, and two months later it dropped to 26 per­cent.

How­ever, wa­ter re­leased from Sterk­fontein Dam be­tween Novem­ber 7 and De­cem­ber 22 as well as sev­eral days of con­stant heavy rain­fall in the area over De­cem­ber and this month have painted a dif­fer­ent pic­ture.

The Vaal is now sit­ting at 52.9 per­cent. Is­lands and riverbeds that were once vis­i­ble dur­ing prior vis­its are now al­most cov­ered, and the area is greener. But this doesn’t mean Gaut­eng res­i­dents can re­lax their ef­forts to use wa­ter wisely.

On the con­trary, if Gaut­eng is go­ing to get through win­ter with­out fur­ther re­stric­tions, res­i­dents must con­tinue to be care­ful with their wa­ter us­age and ad­here to the level two re­stric­tions.

DWS deputy di­rec­tor-gen­eral of emer­gency projects Trevor Balzer said that al­though the Vaal Dam had picked up a sig­nif­i­cant amount of wa­ter over re­cent weeks due to the heavy down­pours, Gaut­eng was far from be­ing out of the woods.

“About one in ev­ery five peo­ple in Gaut­eng re­ceives wa­ter from the Vaal Dam. Pre­to­ria re­ceives about 85 per­cent of its wa­ter from the Vaal Dam, but the run-off in north­ern Joburg and Pre­to­ria flows into rivers like the Jukskei and Croc­o­dile, which lead to Hart­beespoort Dam.

“The rain that falls in south­ern parts of Joburg, Gaut­eng and the Wilge River area in the Free State is what sup­plies the Vaal Dam,” he added.

He said the DWS needed mu­nic­i­pal­i­ties to save 15 per­cent of wa­ter. Mu­nic­i­pal­i­ties not far­ing well in wa­ter sav­ing in­cluded Mid­vaal, Madibeng and Ekurhu­leni.

“How­ever the City of Joburg has man­aged to save 14.4 per­cent and is just below the line, while Pre­to­ria has saved 21.1 per­cent,” Balzer said.

The SA Weather Ser­vice ex­plained to the DWS that with the La Niña weather phe­nom­e­non re­turned to neu­tral, it was dif­fi­cult to pre­dict, but South Africa could see above nor­mal rain­fall in the next few months, and “We need a sig­nif­i­cant amount above that”.

“We need an­other 10 rain­falls like we had in the last week to take us out of the drought sys­tem,” he said.

Balzer em­pha­sised that the Vaal Dam was not the only in­di­ca­tor when look­ing at wa­ter sup­ply lev­els for Gaut­eng.

“The Vaal river sys­tem con­sists of 14 dams, with the Vaal Dam be­ing just one. When peo­ple ask why the re­stric­tions haven’t been lifted if the Vaal Dam is ris­ing, we need them to re­mem­ber it’s just one of 14 dams sup­ply­ing Gaut­eng.

“Be­fore we can look at lift­ing re­stric­tions, we need the level of the Vaal River sys­tem to be at 70 per­cent or above.”

He added that the DWS would re­view whether to main­tain wa­ter re­stric­tions in mu­nic­i­pal­i­ties af­ter May.

As a clap of thun­der was heard over­head, Balzer ex­plained that even dur­ing cloudy con­di­tions there was evap­o­ra­tion over the Vaal Dam.

“It’s shal­low and wide, so this leads to a much higher evap­o­ra­tion rate.

“But Sterk­fontein (Dam) is in a cooler area, it’s small and deep, so it has a much lower evap­o­ra­tion rate, but it takes longer to fill up,” he said.

Spokesper­son for the DWS Sput­nik Ratau said the level of the Vaal Dam was at 44 per­cent full last Fri­day but had in­creased to 52.8 per­cent be­cause of the rain­fall.

While stand­ing on the dam wall he pointed to a grey build­ing in the dis­tance where the wa­ter from the dam only reached its bot­tom. “It should be up to the mid­dle of that struc­ture, so you can see we still have a way to go.

“We need sig­nif­i­cantly above nor­mal rain­fall. We have to re­mem­ber that with high tem­per­a­tures there is also a high evap­o­ra­tion rate. The more rain we get, the bet­ter,” he said.

“We need to take the mu­nic­i­pal­i­ties’ mes­sage se­ri­ously. We must lis­ten to the mes­sage be­ing con­veyed, use wa­ter spar­ingly and bring wa­ter con­sump­tion down,” Ratau con­cluded.

As the group headed back to Joburg and Pre­to­ria, the heav­ens opened and rain be­gan to fall heav­ily once more.

PIC­TURES: KAREN SAN­DI­SON

PROGRESS: The wa­ter line of the Vaal Dam shows weeds and rocks now cov­ered af­ter heavy rains over the past few weeks. The dam is cur­rently sit­ting at more than 52 per­cent full.

HOPE­FUL SIGN: Dark clouds move in over the Vaal Dam.

IT FIG­URES: Trevor Balzer of the Depart­ment of Wa­ter and San­i­ta­tion ex­plains a graph to mem­bers of the me­dia.

Newspapers in English

Newspapers from South Africa

© PressReader. All rights reserved.