Waterways Ireland advises users of the Shannon Navigation that a number of locations throughout the Shannon, in particular harbours and bays, have experienced or are likely to experience algal blooms.

This seasonal phenomenon is evident as a light pea-green and/or green, blue or blue-green colour in the water column on or near the water’s surface.

Information from the HSE’s Interim Fresh Water Algal Bloom Guidance is as follows:

• Affected waters may contain high levels of blue-green algae which may cause illness in humans and animals including pets.
• Avoid contact with scum, visible algae and surrounding water.
• Do not swim or partake in immersive watersport activities in water near visible algae.
• Do not touch scum on the shore.
• Wash hands if you touch the algal material.
• Keep children and pets away from the water’s edge.
• Do not let pets drink the water.
• Wash pets if they come into contact with water.

Waterways Ireland advises masters of vessels that low water levels and fast flows exist between Banagher and Meelick on the Shannon Navigation.

Water levels are currently at or below odinary summer levels in this area. All are requested to observe the 5km speed limits in the Meelick area to prevent squat in shallower areas.

Masters of vessels, particularly those with deep drafts, are advised to navigate with additional caution and to remain within the navigation at all times.

Elsewhere, on the Barrow Navigation, masters and owners on the inland waterway are advised that Clashganny Lock in Co Carlow is temporarily closed for essential repairs.

Waterways Ireland advises masters and owners of vessels that instream work will commence on the new slipway south of the Athlone Lock from tomorrow, Wednesday 4 August.

Works will also take place on the East Bank some 200m south of the weir on the Shannon Navigation. Temporary green navigation aids will be placed on the western extremities of the works area.

Masters of vessels are advised to proceed with additional caution at slow speed and keep to the West Bank while navigating in this area of the inland waterway.

Waterways Ireland has issued a number of advisories for masters and users of the Shannon Navigation over the coming days and weeks.

Where the Shannon meets the River Suck, Pollboy lock gates are on restricted operation until this Saturday 24 July. Vessels with a beam in excess of 12 feet will not be able to through the lock until this time.

Meanwhile, a swimming advisory notice is in place for Lough Allen, Acres Lake, Dromod and Summer Cove. Leitrim County Council has advised that swimming is not recommended at these locations due to reports of poor water quality.

And in Carrick-on-Shannon, navigation and mooring restrictions will be in place on Sunday 1 August to facilitate the Rowing Club Regatta.

The regatta will be held on a 500m stretch of the inland waterway immediately south of the town bridge from 9am to around 6pm. Craft wishing to make a through passage will be facilitated approximately every two hours during the course of the regatta.

Masters should note that only vessels of an overall length of 22ft (6.8m) or less will be permitted on the floating jetties from next Wednesday 28 July to Sunday 1 August. This is necessary in the interest of marine safety and to facilitate the laying of the competition course. Vessels berthed from Wednesday will be required to remain in place until racing finishes the following Sunday.

No vessels should approach the jetties between 4pm on Wednesday and Sunday evening as the entrance to the berths will be closed off and manoeuvring room will be severely restricted due to the proximity of the course.

Masters are advised to proceed at slow speed and with due caution and to take note of advice from course marshals when passing through the area.

Waterways Ireland advises masters and users of the Shannon Navigation that the ESB will be carrying out repairs to the electricity network in the Tarmonbarry area in Co Roscommon tomorrow, Monday 12 July.

As a result, Tarmonbarry lifting bridge and lock will be inoperable behttps://afloat.ie/itemlist/tag/Shannon%20Navigationtween 9am and 4pm during the repair works and no passage will be permitted until their completion.

The cross-border body for Ireland’s inland waterways also notes that due to ongoing mechanical issues, Begnagh Bridge on the Royal Canal will be opened by manual means on the following dates only: Fridays 16, 23 and 30 July and Fridays 6, 13, 20 and 27 August.

Lifts will occur at 12pm on each day and prior notice must be given two days in advance to the water patroller in Clondra at +353 (0)87 915 1400.

Waterways Ireland has issued separate notices for masters and owners of vessels on the Shannon Navigation regarding weed cutting and diving operations.

Weed cutting is currently taking place on the Lecarrow Canal in Co Roscommon and will continue until this Friday 2 July. Masters of vessels are requested to proceed with caution in the vicinity.

Elsewhere, diving operations are scheduled to take place between tomorrow, Thursday 1 July and next Tuesday 6 July in four locations on the Shannon Navigation:

• Portumna: 0.5km above the bridge downriver to the top of Lough Derg
• Shannon Harbour: between Minus Island and Lehinch Island
• Meelick: around Friar’s Island
• Banagher: between Muckinish Island and Inishee Island

Masters of vessels on the inland waterway are requested to proceed with additional caution in the vicinity of the diving operations and follow the instructions of the safety boat crew.

Waterways Ireland has issued an advisory to all vessels on the Shannon Navigation of low water levels, which are currently at or below ordinary summer levels.

Masters of vessels are requested to observe the 5km speed limits on the inland waterways to prevent squat in shallower areas.

All vessels, particularly those with deep drafts, are advised to navigate with additional caution and to remain within the navigation at all times.

Waterways Ireland advises masters and owners of vessels that low water levels exist on the upstream approaches to Meelick and Victoria Lock, north of Portumna on the Shannon Navigation.

Water levels are currently up to 39cm below summer levels as the sluices are open at Meelick Weir, which creates a draw-down of water levels in the area.

Masters of vessels, particularly those with deep drafts, are advised to navigate with additional caution and to remain within the navigation at all times.

Waterways Ireland advises users of the Shannon Navigation that that Tarmonbarry Lock will reopen following emergency lock gate repairs from 9am tomorrow, Saturday 29 May.

Some restrictions in the operation of the gates remain in place, therefore vessels are advised to take additional care when approaching the lock.

Waterways Ireland wishes to advise masters of all craft on the Shannon Navigation of the schedule for the operation of Sarsfield Lock in Limerick, which can be downloaded below.

The lock keeper can also be contacted during the listed operational hours at 087 797 2998. Outside of operational hours a message can be left at thus number. Masters of vessels should provide 24 hours prior notice for lock passage.

Waterways Ireland reminds that due to resource limitations, only in exceptional circumstances will the lock gates be operated outside of the listed hours of operation.