Karachi Harbor
Karachi Harbor, which occupies the lower part of Chinna Creek, has been widened, deepened and considerably improved. It is divided into a lower and upper harbor with principal commercial facilities located on both sides of the upper harbor. The harbor is narrow (minimum 250 yd (229 m) -- maximum 500 yd (457 m)) and heavily congested. A pilot is required and highly recommended. Additionally, it was reported as recently as 1975 that several wrecks were charted incorrectly and that ships should give them a berth of one-half mile. On incoming tidal currents during the southwest monsoon, a considerable swell rolls into the lower harbor near Manora Point. Dredging is continuously in progress to maintain charted depths, but silting is liable to occur during the southwest monsoon.
Ships up to a maximum length of 600 ft (183 m) can enter Karachi Harbor, and vessels with a draft of up to 25 ft (7.6 m) can enter and leave the harbor any time day or night. During the southwest monsoon, vessels drawing up to 32 ft (9.8 m) are permitted to enter and leave port, but this draft maximum may be increased at the discretion of port authorities. Inasmuch as the dredged channel is liable to silting during the southwest monsoon, the permissible draft must be regulated by the conditions of weather and sea.
The total harbor extends about 3-1/2 n mi (6.5 km) north-northwestward and north-northeastward, and ranges from 250 to 500 yd (229 to 457 m) wide between the 20 ft (6.1 m) depth curves. The lower harbor is that portion from Manora Point to the southern end of East Wharf, about 1-1/2 n mi (2.8 km); its navigable channel is reduced, in general, to about 300 yd (274 m) by the banks extending from each side. The upper harbor extends northward and north-northeastward about 2 n mi (3.7 km) and has a navigable width of 300 to 400 yd (274 to 366 m) for most of its length.
In approaching Karachi from the south, there are no good landmarks while passing the delta of the Indus and land is not generally visible until Manora Point comes into view. This approach is particularly dangerous during the southwest monsoon because continuous haze combined with overcast skies make determination of ship's positions difficult. Strong cross currents are experienced during a flooding tide and silting has been very heavy in the channel paralleling the shipyard and naval dockyard. Caution should therefore be exercised during entry and exit because of the rapid silting and flood tide currents.
Getting underway from a Karachi wharf during the southwest monsoon is a problem. Winds up to 20 kt are common, and if a vessel is berthed at East Wharf, the wind sets the ship on the pier. U.S. Navy ships typically have been assigned to wharves 1, 2 or 3 , although these would not be as sheltered as the pierside wharves in the upper harbor.
The major source of pollution in the Karachi Harbor is via Lyari River, which drains huge quantity of untreated mixture of industrial/municipal wastewater into it. About 50 billion cubic meter of sea water enters and leaves the Harbour during a tidal cycle. Due to natural geographical situation of Karachi Harbour, marine pollutants are not completely flushed out into the open sea that makes the Harbour waters hazardous from many aspects. The Karachi Harbor has become one of the most highly polluted Harbors in the region. The untreated municipal and Industrial waste water enriched with a variety of marine pollutants affects the ecological system of adjoining area and poses serious health hazards. In addition, vessels berthed in the Harbor and Harbor infrastructure is also being seriously affected.
All Pakistan Navy [PN] platforms including Surface Ships, S/Ms, Fleet Tankers, Mine Hunters, Missile Boats and Auxiliary craft are berthed at Karachi Upper Harbor and Pakistan Industrial Development Corporation (PIDC) channel at PN Dockyard. Besides negative effects on human health and marine ecology, the polluted Harbour water is seriously affecting the life of these platforms. In addition, it also results into frequent repair/maintenance problems. It becomes difficult to quantify indirect losses to these platforms due to host of variables involved. However efforts have been made to arrive upon an estimated value to have an idea of indirect loss to national exchequer and highlight seriousness of the problem. The same is being explained in subsequent paragraphs.
Mild steel is used in the construction of most of PN vessels. The study conducted by PN Dockyard Laboratory on the rate of corrosion of mild steel shows that standard weight loss of mild steel in the open seawater is only 5.48 gram per square meter per day as compared to 9.20 gram per square meter per day in the Karachi Harbour waters. However, due to various hull preservation techniques this can be reduced but 100% preservation is not possible. Therefore, an estimated value of around 33% loss of ship life has been taken to arrive upon an estimated cost to have an idea of indirect loss to PN. Generally speaking, price of large naval platform in the International market, is around US $ 300 Million. These platforms are usually built for 25-30 years. Loss of 30% ships life as discussed about would means loss of 70.5-90 Million $ US per platform. PN maintains 08 large platforms and 06 submarines. Hence more than one Billion $ US is lost due to the pollution problems and this is huge burden on the national exchequer. These figures will further increase if we take into account small platforms having total number of 26 at present with PN. In other words this cost can be saved if by controlling the pollution in Karachi Harbor as per defined National Environmental Quality Standards (NEQS).
Hull preservation period of naval vessels is about 3 years but due to prevailing condition of Karachi Harbour water, it hardly lasts for one and half year. Therefore, the expenditure cost for hull preservation is almost doubled. It is for information that the one time cost for hull preservation of one fleet tanker is Rs. 10.50 million and for frigate the cost is Rs. 9.00 million. This includes dock charges, grid blasting, painting etc. Marine pollutants reduce economical life of machineries and auxiliaries. Fire and flush pumps, filters, pipes and seals become ineffective and due for frequent replacement in the polluted environment. This results in extra expenditure on their maintenance/replacement. Frequent machinery failures occur in seawater based machinery (i.e. sea suction pumps, fire pumps, DG intakes etc) due to presence of solid waste and plastic bags, thus affecting the efficiency of these systems. This also some time results into failure of some sensitive electronic components which are procured from abroad. Polluted water also reduces the life of Harbour infrastructure i.e. Jetties and docks etc. Huge amount is spent on regular maintenance and repair of the damaged Jetties. For example, at present Rs. 470 million are being spent to refurbish naval jetties along the PIDC channel. It can safely be said that one would have used these berths for another 10-15 years had the Harbor waters been kept in the defined limits. Presence of the floating material/object in the Harbour waters is a potential danger which can cause damage to fast moving platforms. The newly inducted VBSS boat propeller was damaged in the recent past and the same had to be procured from abroad. All the above problems results into enhanced non-operational time thus affecting the sea worthiness and fighting efficiency of these platforms.
