Countering climate change

Climate change challenge

The high tem­per­a­tures and the accom­pa­ny­ing extreme drought were one of the hottest top­ics last sum­mer. The par­tic­u­lar­ly explo­sive nature of the issue can be illus­trat­ed using the munic­i­pal­i­ty of Laue­nau in Low­er Sax­ony as an exam­ple: After con­sump­tion had been too high for days, the water sup­ply col­lapsed last sum­mer. Until well into the fall, the approx­i­mate­ly 4,000 inhab­i­tants were instruct­ed to use water as spar­ing­ly as possible.
But even in the pre­vi­ous­ly quite humid north­ern Black For­est, the per­sis­tent dry phas­es can no longer be ignored. With deliv­ery peaks of up to 30,000 m³ per day, the water sup­ply of Stadtwerke Pforzheim (SWP) set new records. The amount of ground­wa­ter recharge, on the oth­er hand, is con­tin­u­ous­ly decreas­ing. Since 2002, there has not been a sin­gle year in which the ground­wa­ter lev­el has recov­ered. The inter­play of shrink­ing ground­wa­ter reserves and ris­ing con­sump­tion pos­es new chal­lenges for SWP’s drink­ing water load man­age­ment, espe­cial­ly in the sum­mer months. This is because, in addi­tion to the city of Pforzheim, sur­round­ing com­mu­ni­ties are also sup­plied by the SWP water net­work; with an upward trend in consumption.

The status quo

Cur­rent­ly, SWP obtains its raw water from the drink­ing water pro­tec­tion areas in the Nagold Val­ley and the Enza­uen. In addi­tion, the Pforzheim water is sup­plied with long-dis­tance water from the Bodensee­wasserver­sorgung (BMV). The impor­tant resump­tion of drink­ing water sup­ply from the Grös­sel Val­ley is tar­get­ed before sum­mer 2021 by repair­ing the trans­port pipeline along the water pipeline route.
The cen­tral loca­tion for water treat­ment is the Friedrichs­berg water­works. In the mod­ern drink­ing water treat­ment plant, the water from the var­i­ous wells is fil­tered in an ultra­fil­tra­tion plant and by reverse osmo­sis, soft­ened and fed into the water network.
This treat­ment plant already rep­re­sents an impor­tant step in the direc­tion of a mod­ern water sup­ply, but at the same time it also reveals prob­lems that are more like­ly to wors­en than improve in the (near) future: Drink­ing water is becom­ing scarcer, and the load of nitrates, hor­mones and oth­er con­t­a­m­i­nants is increas­ing. Even if the con­t­a­m­i­na­tion with hor­mones and nitrates in par­tic­u­lar is not yet a note­wor­thy prob­lem in Pforzheim, SWP is close­ly mon­i­tor­ing cur­rent devel­op­ments. In par­tic­u­lar, the glob­al increase in water con­t­a­m­i­nat­ed with so-called per­flu­o­ri­nat­ed and poly­flu­o­ri­nat­ed alkyl com­pounds (PFAS, PFT or also PFC), such as those used in fire extin­guish­ing foams, impreg­na­tion sprays or in the tex­tile and paper indus­try, is now even occu­py­ing the atten­tion of politi­cians. These com­pounds can accu­mu­late in human tis­sue over the long term and have very low biodegradability.

The SWP water management strategy

The devel­op­ment described above is con­trary to the val­ue that drink­ing water has — or should have. The pre­am­ble to the EU Water Frame­work Direc­tive states that:
 

“Water is not a com­mon com­mod­i­ty, but an inher­it­ed good that must be pro­tect­ed, defend­ed and treat­ed accordingly.”

 
As a net­work oper­a­tor and water sup­pli­er, SWP there­fore sees it as its duty to fol­low these prin­ci­ples and explic­it­ly align its water man­age­ment accordingly.
To meet these future chal­lenges in water sup­ply, SWP presents its water man­age­ment strat­e­gy. This strat­e­gy is based on sev­er­al pil­lars: The preser­va­tion of sup­ply secu­ri­ty, eco­nom­ic effi­cien­cy, cus­tomer friend­li­ness. In addi­tion, aspects of cor­po­rate man­age­ment, polit­i­cal lev­els and man-made cli­mate change must also be tak­en into account.
Par­tic­u­lar atten­tion must be paid to secur­ing the sup­ply through a sta­ble water net­work, increas­ing the region’s own water pro­duc­tion, and pro­tect­ing resources and the envi­ron­ment or ensur­ing the (hydro-)geological con­di­tions that enable a healthy ground­wa­ter table.
The aim of the strat­e­gy is to ensure in the long term that
 

• the rate of water recharge increas­es again
• the water qual­i­ty is improved and pol­lu­tants are pre­vent­ed from enter­ing the groundwater,
• to pass on the accu­mu­lat­ed know-how to the fol­low­ing gen­er­a­tions as well as to the sur­round­ing com­mu­ni­ties and to sup­port them, and
• the exist­ing water pro­tec­tion areas and zones accord­ing to §51 of the Water Resources Act are secured and extended,

 
in order to enable a region­al and sus­tain­able water man­age­ment and to be able to do with­out the sup­ple­men­ta­tion of long-dis­tance water in the long term.
The focus is in par­tic­u­lar on sup­ply­ing the cit­i­zens of Pforzheim and the sur­round­ing com­mu­ni­ties with healthy, clean drink­ing water and sus­tain­ably sat­is­fy­ing the increas­ing demand.
To accom­plish this, cur­rent laws pro­tect­ing wells and springs must be enforced and the input of any pol­lu­tants as well as land seal­ing — espe­cial­ly where ground­wa­ter resources exist and are used — must be min­i­mized. This is the only way to reduce depen­dence on ener­gy-inten­sive exter­nal water pur­chas­es and to increase water pro­duc­tion from the wells in the low­er Enzauen.
Cen­tral to the project are tan­gi­ble invest­ments in the trans­port sys­tem, for exam­ple in the water sup­ply pipeline from the Grös­sel Val­ley or on the Davosweg. Opti­miz­ing the exist­ing net­work is also part of the water man­age­ment strategy.
Because, this much is cer­tain: The own water resources are suf­fi­cient­ly avail­able. Where­as in recent years the SWP obtained only 36% of its total drink­ing water from region­al springs and wells, the goal is to increase this to 70% of its own water pro­duc­tion by 2030.
For the cit­i­zens and the SWP as a sup­pli­er, this means a pre­ven­tive and sus­tain­able step towards cri­sis pre­ven­tion in the region. By imple­ment­ing clear­ly defined water man­age­ment and cli­mate strate­gies, the SWP pur­sue the pro­tec­tion of the liveli­hood of peo­ple and nature in our region. This sus­tain­able pro­tec­tion goal must not be eclipsed by com­mer­cial plan­ning in water pro­tec­tion areas. These are always asso­ci­at­ed with soil seal­ing and mas­sive inter­ven­tions in the fis­sured sub­soil, as well as with the appli­ca­tion of sub­stances that are harm­ful to the envi­ron­ment and water bod­ies. As a con­se­quence, they rep­re­sent a sus­tained poten­tial threat to the basic secu­ri­ty of the water resources of our fel­low cit­i­zens. Clean drink­ing water is more than a com­mod­i­ty — it is a vital resource and a fun­da­men­tal human right.