MUMBAI, May 19 -- In what could constitute a minor crisis, 2,500-plus unresolved complaints regarding cable faults and other technical issues have remained unaddressed by the BEST Undertaking for months. In South Mumbai, covering Wards A, B, C, D and E, which has only one fuse control room to address 350,000 consumers, the situation is graver, especially in the congested locations of Kalbadevi and Bhendi Bazaar areas where the cables are old. The ageing 80-year-old power cable network, rising power demand, unprecedented summer heat and rapid real-estate expansion has begun to take a toll on the city. The combination of these factors has been causing frequent power outages, moreover outages in localities where there used to be none-a warning that local fixes will not hold for long. Sources in BEST said that the primary reason is the increased demand for electricity. Another reason is the lack of manpower due to the non-filling of vacancies, which has reduced labour by 50% to 70%. A BEST official said that one of the most critical issue was the BMC's refusal to give permission to dig up cement-concrete roads in case of a technical failure or issue with the cables. Added another official: "We end up taking a connection from other lines from the nearest substation to restore the supply. But this puts pressure on other active cables in the network." Sources, however, said that the BMC recently allowed BEST to dig up concrete roads to address issues with extra-high voltage (EHV) lines that cater to multiple phases. The BEST authorities said on Monday that a new control centre-cum-office at Tardeo was being constructed for South Mumbai's five wards. The Undertaking has also completed around 50% of replacement works of the 120-km-long EHV cables. Sources said it would take another two years to replace the remaining ones. Distribution companies blame frequent power outages on the rising demand for power, attributed to the hot weather. Since local plants only generate a fraction of what the city consumes, the remaining 3,650 MW is sucked into the metropolitan region through external transmission networks, putting pressure on receiving substations and ageing underground cables. The total demand of Mumbai has crossed 4,570 Mw of which nearly 1,000 Mw is handled by BEST....