The estimated cost of the stone embankment (known today as the Cob) was £23,500, and a workforce of between 200 and 300 men was engaged, which created problems with accommodating them and feeding them.
Madocks hoped the work would be finished by May 1809, but the work proved to be more difficult than expected.
Stones tipped into the water were carried away by the sands, and the work was battered by both the tides and the waters of the Glaslyn.
Eventually, rush matting was used, to form a foundation onto which the stones could be tipped, a technique well known in Lincolnshire, but not so well known in Wales.
Further progress was made using this method, but there were still two large gaps in the construction.
The construction of stone piers to buttress the bank and the use of boats to dump stones into the gap helped, but the work was hampered by the Glaslyn, which should by this time have been diverted to a new course to reach the sluice gates at Ynys Tywyn at the Porthmadog end.
As it had not yet been diverted, it still flowed down the middle of the estuary, and scoured the back of the embankment.

By this time, Madocks was in ill-health, and was being pursued in the courts for debts, but somehow remained enthusiastic, and in July 1811, the gap was finally closed.
An impromptu celebration was held, which was reported in the North Wales Gazette.
A more formal celebration was held in September, which included a four-day feast, horse racing at Morfa Bychan and an Eisteddfod, which included prizes for the best Welsh Poem on Agriculture and for playing the harp.

Parliament did not re-assemble until January 1812, and Madocks spent his time in Wales trying to resolve his financial affairs and to consolidate the embankment.
As a Member of Parliament, he was immune from civil arrest while Parliament was in session, but only for forty days afterwards, and the long prorogation at the end of 1811 put him at risk of being thrown into Fleet prison, as he was being ceaselessly pursued for debt, but the Under-Sheriff at Caernarfon was clerk to John Evans, Madocks' own solicitor, and so proceedings were conveniently delayed.
With Parliament reconvened, Madocks worked on steering the Boston Harbour Bill through the House of Commons.
The estimated cost of the stone embankment (known today as the Cob) was £23,500, and a workforce of between 200 and 300 men was engaged, which created problems with accommodating them and feeding them. Madocks hoped the work would be finished by May 1809, but the work proved to be more difficult than expected. Stones tipped into the water were carried away by the sands, and the work was battered by both the tides and the waters of the Glaslyn. Eventually, rush matting was used, to form a foundation onto which the stones could be tipped, a technique well known in Lincolnshire, but not so well known in Wales. Further progress was made using this method, but there were still two large gaps in the construction. The construction of stone piers to buttress the bank and the use of boats to dump stones into the gap helped, but the work was hampered by the Glaslyn, which should by this time have been diverted to a new course to reach the sluice gates at Ynys Tywyn at the Porthmadog end. As it had not yet been diverted, it still flowed down the middle of the estuary, and scoured the back of the embankment.
By this time, Madocks was in ill-health, and was being pursued in the courts for debts, but somehow remained enthusiastic, and in July 1811, the gap was finally closed. An impromptu celebration was held, which was reported in the North Wales Gazette. A more formal celebration was held in September, which included a four-day feast, horse racing at Morfa Bychan and an Eisteddfod, which included prizes for the best Welsh Poem on Agriculture and for playing the harp.
Parliament did not re-assemble until January 1812, and Madocks spent his time in Wales trying to resolve his financial affairs and to consolidate the embankment. As a Member of Parliament, he was immune from civil arrest while Parliament was in session, but only for forty days afterwards, and the long prorogation at the end of 1811 put him at risk of being thrown into Fleet prison, as he was being ceaselessly pursued for debt, but the Under-Sheriff at Caernarfon was clerk to John Evans, Madocks' own solicitor, and so proceedings were conveniently delayed. With Parliament reconvened, Madocks worked on steering the Boston Harbour Bill through the House of Commons.
William Madocks