The name Karmanasa means ‘destroyer of good deeds’. So before giving an account of the various bridges constructed across the Karmanasa River, it is important to relate the mythological story that made this river an inauspicious one for Hindus as well as Budhhists. The ominous quality of the river was one of the primary reasons for Hindus to build a bridge over the river as it formed a major obstacle to cross for those Hindus from the east wanting to visit important pilgrim places such as Benares, Allahabad and Vindhyachal near Mirzapur.
Gautama Budh, while writing about the sanctity of city of Gaya, stated that, ‘by the touch of water of Karmanasa, all virtuous works are instantly destroyed.’ The Padma-Purana relates a long story on the cause of the misfortune addressed to the Karmanasa River:
After Ravana abducted Sita and took her to Lanka, Hanuman and his followers surrounded his fortress and threatened to destroy Lanka if Sita was not returned. Ravana in order to gain protection for his beautiful city Lanka, prayed to Shiva for assistance. The prayer only managed to invoke a goddess who directed him to obtain a Shivling from Kailash Mountain and carry it to Lanka without placing it even once on the ground during the journey. Ravana obtained the Shivling and on his return, near Baidyanath Hill was accosted by Indra in the garb of a Brahmin. Indra and Varuna, the lord of water, concerted together a plan to stop Ravana from succeeding in his mission. Varuna in his invisible entered the belly of Ravana and created immense discomfort causing him to pause in his journey. He called upon the Brahmin who was Indra disguised as such to help him with the Shivling by holding it for the time Ravana took time to recover from the strange and sudden affliction of stomach pain and discomfort. The Brahmin willingly extended assistance and the moment Ravana handed the Shivling to him, he placed the Shivling of the ground, where it immediately became fixed and permanent. Meanwhile, Varuna had filled Ravana’s stomach with so much water that it soon got discharged and formed a river which was called Karmanasa. And, thus, the water of the river acquired the defiling qualities so abhorred by the Hindus.
Another legend, that is often shared, is that a highly aspiring Rajah Trisanku, father of Raja Harishchandra, wanted to achieve an exalted position among the gods in his material body. To achieve this wish, he requested Rishi Vasistha to assist him but the Rishi refused to help him. The Raja then went to Vasistha’s sons who got irritated by his demand and thus cursed him and turned him into Chandala. Angry and humiliated, Raja Trisanku rushed to Rishi Vishwamitra, who was a rival of Rishi Vasistha, for help. Rishi Visvamitra agreed to help the Raja in achieving his desire. He set a big yagna to which all the Rishis were invited. Rishi Vasistha declined the invitation. At the completion of a successful yagna, Raja Trisanku started ascending towards heaven in his material body. However, displeased by this, the gods stopped his entry and kicked him out of their abode. In the battle of egos between the gods and Rishi Visvamitra, Raja Trisanku became stuck in limbo between the earth and the heaven in an awkward position. The anguished caused tears from Raja Trisanku to flow, which formed the Karmanasa River.
The Karmanasa River is nearly 192 km long and flows in a south-north direction to join the Ganges at village Chausa located in the district of Buxar, Bihar. Despite being a difficult obstacle for the movement of people and goods between the territories of Bengal and North-West Provinces, the river was never successfully bridged even though attempts were made.
According to some sources, several attempts were made in distant past to throw a bridge across the said river but every attempt failed which lent credence to the ominous nature of the river. During the reign of Aurangzeb, the Subadar of the Benares district through attempted to create a bridge over the river. This structure was never completed because remnants of an incomplete structure were visible over a century later, in the early nineteenth century. In the middle of the eighteenth century Rai Bhara Mal, who, according to some was a Diwan of Himmat Bahadur, a Gosain leader, and according to others Diwan of Dara Shikoh, began another effort to ford the river near the village of Naubatpur, but faced failure like the others in the past. In 1780, the prolific builder of public and religious buildings Ahilya Bai took interest in the matter and directed her workers, who were involved in creating several ghats at Benares, to ford the river at the same spot as that of Rai Bhara Mal. However, there is no evidence of any work done by her workers.
Towards the turn of the nineteenth century, during the period of Mr Duncan at Benares, Nana Fadnavis took serious interest in fording the river and put in nearly ten years of labour and over rupees fourteen lakhs (some doubt this figure and state in reality it was between rupees two to three lakhs). His death put a sudden stop to the effort. Nevertheless, in those ten years, Nana Fadnavis was successful in creating secure foundations in river which had a ‘soil formed of deep oozing sand.’ To build houses and other construction work, Zamindars and villagers of nearby places carried away parts of the large quantity of material collected for the construction of the bridge. Some were used to built a large well in a village in the vicinity.
In 1820s, public-spirited Indian elite Raja Shiv Chander Rai hired the services of Mr Colin Shakespeare, an engineer in the service of the East India Company, to construct a rope suspension bridge across this river. The British government supported and lauded this effort. This bridge had a 300 feet span and could accommodate foot passengers and dak runners. The coir rope used in the construction of this bridge was tarred to give it extra strength. Soon it was felt that this rope bridge should be replaced by an iron bridge, for which a person was deputed to do a study for its erection. However, the idea was dropped and in its place, it was felt prudent, to build a masonry bridge.
Rai Patni Mal of Benares volunteered the building of this masonry bridge. Rai Patni Mal was known for his munificence towards erecting ghats, tanks, and temples at places like Benares and Mathura. He offered to complete the bridge started by Nana Fadnavis but his family were not supportive of this project as they feared some bad omen might befall him and large sums of money would be wasted on a fruitless project. Rai Patni Mal, however, stood his ground. At the commencement of the project his wife expired, which could have been taken as an evil omen, but Patni Mal was undeterred. The government, also, by then had not accepted any of the terms under which he had offered to build the bridge. The terms were:
1) Permission to use the materials formerly collected
2) Assistance from the police in procuring carts, &c
3) The Services of a Secretary to the Benares Committee of Improvements, who had furnished a design for the new bridge
4) A remission of the heavy duties on Chunar stone
5) A confirmation of the title of Raja Bahadur Neknam, which had been conferred upon him by the king of Delhi, during Mr Seton’s residency
Point number four above was addressed by the opening a quarry nearby instead of carting and paying duty on the stone from Chunar. This quarry was located fourteen miles to the south-west of Naubatpur.
Source: Gleanings in Science, October 1831, Volume III, January to December 1831, pp. 297-300.
The details of the bridge are given below. Rai Patni Mal executed two changes to the original plan, which is displayed in plate given in the source. The first change he made was to omit the semi-domes over the recesses on the piers and, the second change was to create plain parapet on the wing walls instead of a balustrade.
The original native bridge was to have seven arches of 17 feet span; to take advantage of the piers already built it was determined to throw two of these into one, making three equal arches, which with the piers should occupy precisely 200 feet in span. The semicircular form was preferred on account of the great rise of the river, the necessary height of the road way, the symmetry of the elevation, (since for more than 8 months of the year, the level of the water remains 2 steps below the spring of the arch as shewn in the sketch,) and the convenience of cutting the stones to one model. The span of the arches is 53 feet, and the depth of the voussoirs 3 feet. A vault of brick is laid over them to prevent any infiltration of water through the joints from above. To the piers is given a section of 30 by 13 feet: the roadway is 25 feet wide, and perfectly horizontal. The centering consisted of 6 frames, each composed of four pieces (fig. 3) so as to be as light as possible; for it must be remarked, that no machinery could be employed in the construction: – every stone was to be raised and posited by direct human labour; – figures 5, 6, and 7 are intended to exemplify one instance of this in the simple native mode of carrying stones: the number of men is increased according to the weight to be lifted, and from the combination of levers, the weight necessarily bears equally upon the supporting shoulders of all the pesrajes or carriers; with a saugar of 16 men they readily move a stone of as many maunds or about fourteen cwt.
When the construction started it was found that the coffer dams or kothi of stone had been laid across the bed of the river for a width of 60 feet thereby constructing a solid rock bed. Most of these kothi reached 20 feet below the bed of the river, firmly standing on hard clay. Some of these kothi of stones were filled with masonry which reduced the time and effort in building piers on them. In April of 1830, the first arch ‘was turned’ and two other arches were commenced. And by July of 1831 the roadway was nearly completed. This despite the fact that on one occasion a sudden rise of water by 26 feet carried away parts of arches under construction.
The estimated cost of the bridge as incurred by Rai Patni Mal was Rs 100,000. This was exclusive of the cost incurred by Nana Fadnavis previously. It is reported than Rai Patni Mal’s son, Rai Ram Kishen acted as the superintendent of the project which ensured proper management of funds. Captain Grant, an officer of EIC in the Benares Division, gave valuable advice and inputs in the construction and frequently visited the site to ensure proper execution of the works. However, the whole detail of construction was conducted by Indian masons, and the construction quality was so good that the British officers commended the skills and exertions of the Indian masons.
This masonry bridge still stands (the bottom one) as can be seen in this Google Map snapshot.
Source: Courtesy Google Maps.
 Wopendranath Ghosh, Rohtas Garh (Cuttack: Orissa Mission Press, 1908), pp. 4-5.
 H. M. Elliot, The History of India as told by its own Historians: The Mohammadan Period, Volume VII, ed., John Dowson (London: Trubner and Co, 1877), p. 168.
 Colin Shakespeare, ‘Portable Bridge of Suspension,’ in Transactions of the Society, Instituted at London, for the Encouragement of Arts, Manufactures, and Commerce, Vol. 43 (1824), pp. 160-182.
 ‘Summary of the Latest Intelligence from the East,’ in The Oriental Herald, Vol. VIII, January to March, 1826 (London), pp. 353- 376.
 Gleanings in Science, October 1831, Volume III, January to December 1831, pp. 297-300.
 Gleanings in Science, October 1831, Volume III, January to December 1831, pp. 297-300.
 The kothis of stone rested upon a wooden frame or jamwat, which is sunken through the sand by the process of under-digging, as practised by the well-diggers of Bengal.
 The Caramnassa Bridge, Gleanings in Science, No. 34, October, 1831, January to December, 1831, Volume III (Calcutta), pp, 297-300.