Missing manholes: culprit to floods?
With the advent of Ondoy, Pepeng, Sendong, and other typhoons, floods in Metro Manila are already unexceptional especially during rainy seasons. But last July, Metro residents experienced few consecutive unusual flooding.
Metro Manila Development Authority (MMDA) said that due to flash floods, some streets appear to be impassable to light vehicles. They added that gutter-deep floods, knee-high level and chest-deep floods were also noted particularly on some parts of Quezon City, Manila and southern parts of metro like Paranaque and Makati forcing many schools to cancel classes and government offices to call off operations.
One of the few reasons pointed to recent unusual floods is the missing manholes which have been plugged by private contractors of the Department of Public Works and Highways (DPWH) while asphalting major thoroughfares in Metro Manila. Based on MMDA’s summary report, there are 661 manholes overlaid with asphalt.
MMDA chairman Francis Tolentino said that they have already asked the DPWH-National Capital Region to immediately solve this matter and penalized heedless contractors who are accountable for asphalting manholes.
“Contractors must be held responsible for this. They should face fines and penalties like withholding their retention fees and if they continue with this kind of work, be blacklisted from conducting government projects,” he cited.
Tolentino stressed that missing manholes could contribute a lot to recent floods because manholes which have been covered can cause difficulty to MMDA workers for its clearing and declogging operation.
“Waste deposit buildups are hard to reach, there is slow receding of flood water, which result in flooding and traffic jams,” he added.
Discrepancy in records
On the other hand, in an interview with the DPWH Maintenance OIC Reynaldo Rosario, he confirmed that there are 471 total numbers of manholes in Metro Manila and verified that only 243 manholes were overlaid with asphalt.
When asked why MMDA’s report and theirs are inconsistent, Rosario said that MMDA included some utility manholes which are not part of DPWH properties like Philippine Long Distance Telecommunication Company (PLDT) and Metropolitan Waterworks and Sewerage System (MWSS) and some manholes located in the sidewalk which are not cover of asphalting.
“There are two different kinds of manholes: A circular manholes which are owned by MWSS, PLDT and municipalities and rectangular or square manholes which are ours. Utility manholes are out of our liability,” he added.
As such, then why DPWH didn’t appeal to MMDA and media for clearing up fallacies in the total numbers of manholes overlaid that was reported by MMDA?
“In the name of companionship, you know MMDA and DPWH are two government sectors that work jointly in road matters. Thus, we support each other,” Rosario answered.
Rosario explained that during asphalting, the contractors will overlay the whole roads including the manholes. Manholes location will be marked before asphalting to be retrieved after. So what is the cause of missing manholes? Do asphalts overlaid clog the watercourse inside manholes?
“Overlaid asphalts will not clog the manholes because it has steel or concrete cover, what makes missing manholes to be pointed out as major cause of floods is that when it is overlaid, MMDA will have a hard time identifying its location and removing the silt and waste in it which impedes the flow of floodwater”, he defended.
“We have also our own fault because after asphalting procedure, some of the contractors forget to retrieve the manholes,” admitted Rosario.
Meanwhile, South Manila Flood Control Operations District (SMFCOD) Engr. Alexander Mohammad said that the main reason to the missing manholes he saw was due to time constraints. Most of DPWH works like road improvements and constructions usually take place by night to avoid inconvenience to motorists and commuters causing some of the contractors to rush working and neglect fetching the manholes after.
Despite the blames being drawn to them, Rosario insisted that missing manholes is just a small factor to worsening of floods.
“It just so happened that road repairs and improvements extends up to June and July where it is rainy season and there’s no one to partly blame but the missing manholes. This is just a petty reason to be pointed out. There’s much more, like human’s discipline on proper disposal of garbage and waste materials and informal settlements,” he added.
He also compared floods in metro to a sink with narrow inlet where water when suddenly poured became still but after a few seconds, subsides slowly.
“That’s flood in Manila, it might stay for long hours, but it will not take months to subside,” ended Rosario.
On the way to clearing up
As of September 2012, DPWH indicated that 75% of the missing manholes are already retrieved and estimated that by October they have already retrieved all the remaining overlaid manholes in Metro Manila.
DPWH plans to add big pumping stations in Metro Manila only if an enough budget will be provided by the government.