A HydroSack or a HydroSnake is a brand name for a flood control sandbag alternative made by Gravitas International of Cheshire, North West England. [1] They are very lightweight and thin until they come into contact with water, then they begin to retain water until they have reached capacity. The devices then resist any further water excess. These can be used to absorb, resist and redirect flowing water.
The HydroSack and the HydroSnake are made up of an outer fabric consisting of non-woven polypropylene with a hydrophilic finish. The internal pads are composed of pads containing wood pulp and a superabsorbent polymer (SAP). In this form, the HydroSack or HydroSnake weighs 0.5 kilograms (1.1 lb). The HydroSack measures 60 by 48 centimetres (24 by 19 in) and the HydroSnake measures 20 by 120 centimetres (7.9 by 47.2 in). When a HydroSack or a HydroSnake comes into contact with water, the SAP crystallizes and absorbs the water. [2] HydroSacks take approximately 2-3 minutes to reach full capacity. The HydroSack and the HydroSnake are very absorbent. [1] Full capacity is between 15–20 litres (4.0–5.3 US gal) of water. It retains this weight for up to six months. HydroSacks can be stacked together to form a strong ballast. It is used as a form of flood control and can be used to minimize the damage that flooding can cause. [3] The HydroSack has a three-section structure with handles. [1] When a HydroSack is no longer needed, the insides can be emptied into the earth after use, without any harmful effects.
HydroSacks and HydroSnakes are new innovations to replace sandbags for their multiple purposes, from road ballast signs to flood protection. Globally, other companies are making products similar to the HydroSack, such as UK-based FloodSax which have sold more than 2.5 million of their alternative sandbags worldwide and Thailand based Nanotec. [4] Fife council in the United Kingdom recently integrated the HydroSack into their first response flood protection. [5] In June 2013, some residents of Rosyth criticized the distribution of HydroSacks for flood control, complaining that they were a single-use, disposable product. The Fife Council confirmed this, but added they would last for two or three months once filled with water. [2]
A levee, dike, dyke, embankment, floodbank, or stop bank is a structure used to keep the course of rivers from changing and to protect against flooding of the area adjoining the river or coast. It is usually earthen and often runs parallel to the course of a river in its floodplain or along low-lying coastlines.
A flood is an overflow of water that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding. Examples for human changes are land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees. Global environmental issues also influence causes of floods, namely climate change which causes an intensification of the water cycle and sea level rise. For example, climate change makes extreme weather events more frequent and stronger. This leads to more intense floods and increased flood risk.
Fife is a council area, historic county, registration county and lieutenancy area of Scotland. It is situated between the Firth of Tay and the Firth of Forth, with inland boundaries with Perth and Kinross and Clackmannanshire. By custom it is widely held to have been one of the major Pictish kingdoms, known as Fib, and is still commonly known as the Kingdom of Fife within Scotland. A person from Fife is known as a Fifer. In older documents the county was very occasionally known by the anglicisation Fifeshire.
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower. Hydropower supplies 14% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants. However, when constructed in lowland rainforest areas, where part of the forest is inundated, substantial amounts of greenhouse gases may be emitted.
Inverkeithing is a coastal town, parish and historic royal burgh in Fife, Scotland, on the Firth of Forth, 9.5 miles northwest of Edinburgh city centre and 4 miles south of Dunfermline.
Dunfermline Athletic Football Club is a Scottish professional football club based in the city of Dunfermline, Fife. Founded in 1885, the club currently compete in the Scottish Championship after winning the 2022–23 Scottish League One title. Dunfermline play at East End Park, are nicknamed The Pars and are currently managed by James McPake.
Limekilns is a historic coastal village in Fife, Scotland. It lies on the shore of the Firth of Forth, around 3 miles (5 km) south of Dunfermline and 13 miles (21km) northwest of Edinburgh.
A sandbag or dirtbag is a bag or sack made of hessian (burlap), polypropylene or other sturdy materials that is filled with sand or soil and used for such purposes as flood control, military fortification in trenches and bunkers, shielding glass windows in war zones, ballast, counterweight, and in other applications requiring mobile fortification, such as adding improvised additional protection to armored vehicles or tanks.
Hessian, burlap in North America, or crocus in Jamaica and the wider Caribbean, is a woven fabric made of vegetable fibres, usually the skin of the jute plant or sisal leaves. It is generally used for duties of rough handling, such as making sacks employed to ship farm products and to act as covers for sandbags, and for wrapping tree-root balls. However, this dense woven fabric, historically coarse, more recently is being produced in a refined state, known simply as jute, as an eco-friendly material for bags, rugs, and other products.
A flood barrier, surge barrier or storm surge barrier is a specific type of floodgate, designed to prevent a storm surge or spring tide from flooding the protected area behind the barrier. A surge barrier is almost always part of a larger flood protection system consisting of floodwalls, levees, and other constructions and natural geographical features. Flood barrier may also refer to barriers placed around or at individual buildings to keep floodwaters from entering the buildings.
A ballast tank is a compartment within a boat, ship or other floating structure that holds water, which is used as ballast to provide hydrostatic stability for a vessel, to reduce or control buoyancy, as in a submarine, to correct trim or list, to provide a more even load distribution along the hull to reduce structural hogging or sagging stresses, or to increase draft, as in a semi-submersible vessel or platform, or a SWATH, to improve seakeeping. Using water in a tank provides easier weight adjustment than the stone or iron ballast used in older vessels, and makes it easy for the crew to reduce a vessel's draft when it enters shallower water, by temporarily pumping out ballast. Airships use ballast tanks mainly to control buoyancy and correct trim.
The Wivenhoe Dam is a rock and earth-fill embankment dam with a concrete spillway across the Brisbane River in South East Queensland, Australia. The dam takes it names from the local Wivenhoe Pocket rural community. The dam wall is located about 80 kilometres (50 mi) by road from the centre of Brisbane. The primary purpose of the dam is the supply of potable water for the Brisbane and Ipswich regions. The dam also provides for flood mitigation control, hydroelectricity, and recreation. The impounded reservoir is called Lake Wivenhoe and the dam, the lake and a narrow strip of surrounding land forms a locality also called Lake Wivenhoe.
Surface runoff is the unconfined flow of water over the ground surface, in contrast to channel runoff. It occurs when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the soil is saturated by water to its full capacity, and the rain arrives more quickly than the soil can absorb it. Surface runoff often occurs because impervious areas do not allow water to soak into the ground. Furthermore, runoff can occur either through natural or human-made processes.
A stand-alone power system, also known as remote area power supply (RAPS), is an off-the-grid electricity system for locations that are not fitted with an electricity distribution system. Typical SAPS include one or more methods of electricity generation, energy storage, and regulation.
A superabsorbent polymer (SAP) (also called slush powder) is a water-absorbing hydrophilic homopolymers or copolymers that can absorb and retain extremely large amounts of a liquid relative to its own mass.
Flood control methods are used to reduce or prevent the detrimental effects of flood waters. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and runoff. Flood control methods can be either of the structural type and of the non-structural type. Structural methods hold back floodwaters physically, while non-structural methods do not. Building hard infrastructure to prevent flooding, such as flood walls, is effective at managing flooding. However, best practice within landscape engineering is more and more to rely on soft infrastructure and natural systems, such as marshes and flood plains, for handling the increase in water.
A check dam is a small, sometimes temporary, dam constructed across a swale, drainage ditch, or waterway to counteract erosion by reducing water flow velocity. Check dams themselves are not a type of new technology; rather, they are an ancient technique dating from the second century AD. Check dams are typically, though not always, implemented in a system of several dams situated at regular intervals across the area of interest.
Ballast water discharges by ships can have a negative impact on the marine environment. The discharge of ballast water and sediments by ships is governed globally under the Ballast Water Management Convention, since its entry into force in September 2017. It is also controlled through national regulations, which may be separate from the Convention, such as in the United States.
Water crystal gel or water beads or gel beads is any gel which absorbs and contains a large amount of water. Water gel is usually in spherical form and composed of a water-absorbing superabsorbent polymer such as a polyacrylamide.
AquaFence is a reusable temporary flood and hurricane barrier made by the Norwegian manufacturer AquaFence. It is an alternative to other temporary floodwater control such as sandbags and to the building of permanent seawalls.