As the storm clouds gather

In the last few days, temperatures in Jeddah have dropped, the wind shifted to a brisk southerly, and clouds have moved in. High over the Sarawat Mountains to the east of the city heavy clouds gather, the result of the onshore breeze being forced upward into the cooler air. In the convergence zone between relatively warm sea air and the cold above the mountains, fluffy cumulus clouds heavy with moisture build, increasing a little in volume each day. Rain seems imminent and with it, the fears of the citizens of east and south Jeddah who remember Jan. 26, 2011 floods. Early in the morning the rains came in quantity, tumbling down the wadis that scar the land west of the Sarawat Mountains. The water gathered momentum as tributaries. Much of the water hit the eastern suburbs of Jeddah before day broke, causing death and destruction on a grand scale. Just as residents thought the worst was over, as the water level stabilized, the worst happened: Umm Al-Khair Dam gave way in a spectacular collapse and added millions of tons of accumulated water to the disaster area. The effect was to create a surge and cause a second wave of water damage on a scale the city had never before seen. After the deluge had receded and when the damage had been assessed, recriminations and the blame-game began. Decisive action by Custodian of the Two Holy Mosques King Abdullah cut through the bluster and the decree was made to build dams of a quality and size to ensure that the humanitarian disaster could not happen again. Jeddah-based Huta Hergafeld was tasked with the seemingly impossible job of building not one, but six new dams in ten months. The work involved was simple enough in principle. Deep footed foundations, a concrete barrier several meters thick and inclined walls to provide support and extra protection. It was perfectly within Huta Hergafeld’s engineering remit. One would have been a standard engineering challenge; six in ten months was a completely different scale. Mobilizing their resources and experience gained in marine engineering, they succeeded, and although bearing rather unprepossessing designations such as M1 and Q2, the dams are massive, very solid and — to the residents downstream — very reassuring structures. With substantial concrete cores and walls of country rock, they span six wadis and form a barrier to westward flowing water. Still the clouds build; the acid test is yet to come. The question is whether the dams, a result of decisive action, marine-informed design and huge effort, have produced an effective barrier against any repeat of Jan. 26 2011. Tens of thousands of Jeddawis pray they have.