Editing River Shannon (section)

==Navigation==
[[Image:ShannonRiversml.png|thumb|right|Course of River Shannon]]

===1755 to 1820===
Though the Shannon has always been important for navigation in Ireland, there is a fall of only {{convert|18|m|abbr=on}} in its first {{convert|250|km|abbr=on}}. Consequently, it has always been shallow, with {{convert|0.5|m|abbr=on}} depths in various places. The first serious attempt to improve navigability came in 1755 when the [[Commissioners of Inland Navigation]] ordered [[Thomas Omer]], a new immigrant from England, possibly of Dutch origin, to commence work.<ref>{{cite book|author=Ruth Delaney|title=Ireland's Inland Waterways|publisher=Appletree Press|year=2004}}</ref> He worked at four places between [[Lough Derg (Shannon)|Lough Derg]] and [[Lough Ree]] where natural navigation was obstructed, by installing lateral canals and either [[pound lock]]s or [[flash lock]]s. He then continued north of Lough Ree and made several similar improvements, most notably by creating the first [[Jamestown Canal]] which cut out a loop of the river between [[Jamestown, County Leitrim|Jamestown]] and [[Drumsna]], as well as lateral canals at [[Roosky]] and [[Lanesborough, Longford|Lanesborough]].<ref>{{cite book|author=Ruth Delaney|title=Ireland's Inland Waterways|publisher=Appletree Press|year=2004}}</ref>

The lower Shannon between [[Killaloe, County Clare|Killaloe]] and [[Limerick]] had a topography quite different from the long upper reaches. Here the river falls by {{convert|30|m|abbr=on}} in only {{convert|20|km|mi|abbr=on}}. William Ockenden, also from England, was placed in charge of works on this stretch in 1757 and spent £12,000 over the next four years, without fully completing the task. In 1771 parliament handed over responsibility to the [[Limerick Navigation Company]], with a grant of £6,000 to add to their subscriptions of £10,000. A lateral canal, {{convert|8|km|0|abbr=on}} long with six locks, was started but the company needed more funds to complete it. In 1791, [[William Chapman (engineer)|William Chapman]] was brought in to advise and discovered a sorry state of affairs – all the locks had been built to different dimensions and he spent the next three years supervising the rebuilding of most of them. The navigation was finally opened in 1799, when over {{convert|1000|LT|t|abbr=off}} of corn came down to Limerick, as well as [[slate]]s and [[Peat|turf]]. But even then, there were no [[tow path]]s in the river sections and there were still shoals in the summer months, as well as a lack of harbour facilities at Limerick, and boats were limited to {{convert|15|-|20|LT|t|abbr=off}} load, often less.{{citation needed|date=August 2024}}

With the approaching opening of the [[Grand Canal (Ireland)|Grand Canal]], the Grand Canal Company obtained permission from the [[Directors General of Inland Navigation]], and asked [[John Brownrigg (surveyor)|John Brownrigg]] to do a survey which found that much of Omer's work had deteriorated badly, so they started repairs. After protracted negotiations on costs and conditions, the work was completed by 1810, so that boats drawing {{convert|5|ft|9|in|abbr=on|order=flip}} could pass from [[Athlone]] to [[Killaloe, County Clare|Killaloe]]. Improvements on the lower levels were also undertaken, being completed by 1814.{{citation needed|date=August 2024}}

When the [[Royal Canal]] was completed in 1817 there was pressure to improve the navigation above Lough Ree. The Jamestown Canal was repaired, harbours built and [[John Killaly]] designed a canal alongside the river from [[Battlebridge, County Roscommon|Battlebridge]] to [[Lough Allen]], which was opened in 1820.{{citation needed|date=August 2024}}

===1820s to Independence===
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[[File:Boats on shannon rally.JPG|thumb|left|2012 Shannon Boat Rally]]
In the latter part of the 1820s, trade increased dramatically with the arrival of paddle-wheeled [[steamboat|steamers]] on the river which carried passengers and goods. By 1831 14,600 passengers and {{convert|36000|LT|t|abbr=off}} of freight were being carried. This put new pressure on the navigation and a commission was set up resulting in the [[Shannon Navigation Improvement Act 1835]] ([[5 & 6 Will. 4]]. c. 67) appointing five commissioners for the improvement of navigation and drainage who took possession of the whole navigation. Over the next 15 years, many improvements were made but in 1849 a railway was opened from Dublin to Limerick and the number of passengers fell dramatically. Freight, which had risen to over {{convert|100000|LT|t|abbr=off}} per year, was also halved.

But the work the commissioners carried out failed to solve the problems of flooding and there were disastrous floods in the early 1860s. Given the flat nature of most of the riverbank, this was not easily addressed and nothing much was done till the twentieth century.

===Ardnacrusha and passenger use===
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[[File:Shannon at Limerick.jpg|thumb|right|River Shannon at [[Limerick]], where it flows into the [[Shannon Estuary]]]]
One of the first projects of the [[Irish Free State]] in the 1920s was the [[Shannon hydroelectric scheme]] which established the Ardnacrusha [[power station]] on the lower Shannon above Limerick. The old Killaloe to Limerick canal with its five locks was abandoned and the head race constructed from Lough Derg also served for navigation. A double lock was provided at the dam.

In the 1950s traffic began to fall and low fixed bridges would have replaced opening bridges but for the actions of the [[Inland Waterways Association of Ireland]] which persuaded the [[Tánaiste]] to encourage passenger launches, which kept the bridges high enough for navigation. Since then the leisure trade has steadily increased, becoming a great success story.