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Welcome to the Pacific HYCOS Showcase page where project activities are 'showcased' using different types of media such as video footage and digital photographs.
2nd Pacific HYCOS Steering Committee Meeting
The 2nd Pacific HYCOS Steering Committee meeting was held 23rd - 24th July 2008 in Niue. The meeting was officially opened by the Honourable Minister O'love Jacobsen.
Digital Videos
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By clicking on the following links you can view digital video footage of activities carried out in different countries.
Hydrological Equipment
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The following is a list of hydrological equipment available under Pacific HYCOS.
Current Meters
Current meters are used to measure velocity at different depths in flowing bodies of water. Depth of water and velocity will determine which size current meter is suitable. The photos below show examples of different size current meters.
Sounding Weights and Gauging Rod
Depending on the depth of water a current meter can be mounted to different accessories such as a sounding weight (aka "Bomb") or a gauging rod as shown below.
Sounding Winch
A current meter can be attached to a sounding winch which can then be attached to the back of a boat.
Counters, Loggers, Samplers, Water Level Meter with ER, Water Quality Kit, Divers and GPS
Current meter counters, mini loggers, sediment samplers, water level meter with ER, water quality test kits, divers and GPS are also available under Pacific HYCOS.
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b) Mini logger |
c) Sediment sampler |
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d) Water Level Meter with ER
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e) Water quality test kit
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f) Survey equipment
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g) Diver
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h)Diver |
i) Diver Data Download |
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j) GPS
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Computer Equipment and Digital Cameras
Under Pacific HYCOS, each of the 14 Project countries will receive a 'ToughBook' computer (a laptop computer built specifically for rough terrain use) and digital camera.
Operations and Maintenance ("O&M")
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Correct maintenance is one of the major influencing factors toward the optimum life of hydrological equipment. Pacific HYCOS provides the following links to PDF versions of operations and maintenance manuals.
Rainfall Manuals
Surface Water
Groundwater
The Importance of Pacific HYCOS and Hydrological Data
Why does Pacific HYCOS exist? A valid question. Imagine attempting to manage something you cannot measure. Here’s an example: Attempt to draft a budget without knowing how much money you have to spend, or, how to meet the water demands of a community without knowing how much water you receive annually. You begin to understand the challenge.
Reliable hydrological data sets are difficult to acquire throughout the 14 Project member countries, there importance is incredibly valuable toward sustainable development in the region.
The aim of a hydrological cycle observation system (HYCOS) is to collect hydrological data to improve the accuracy, availability, dissemination and ease of use of water resources data and information.
Data collected from rain water, surface water and ground water is needed by a number of individuals, as outlined in the table below, through the development and implementation of appropriate national water resources information systems.
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Who
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Why / What
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1. Hydrologists and Hydro-Geologists
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· Better definition of the hydrological cycle in a specific hydrological regime
· Urban & rural water supplies
· Identification of sustainable abstraction rates (surface & groundwater)
· Groundwater assessment
· Catchment erosion & sedimentation
· Groundwater modeling & flow paths
· Development of return periods for floods, droughts and other parameters
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2. Engineers and Designers
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· Bridge & culvert design
· Road design
· Catchment modeling for areas of competing use in a single or multi catchment water transfer environment, eg, potable water supply, irrigation, hydro electric
· Development of IFD data (intensity, frequency, duration) for use in models and design data for urban & rural drainage, rainfall runoff models
· Irrigation design
· Hydroelectric design (run of river & storage) reservoir and spillway design
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3. Coastal Engineers
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· Coastal protection
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4. Planners
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· Long term national interest (trends, changing catchment conditions, climatic change)
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5. Environmentalists
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· A sound basis for compliance monitoring
· Environmental claims
· Consideration of environmental/riparian flows
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6. Scientists & Academics
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· Modeling
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7. Disaster Risk Managers
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· Flood estimates, flood modeling, flood forecasting & warning
· Flood mitigation schemes (including hydrological and hydraulic modeling)
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8. Meteorologists
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· Low flow & drought analysis
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9. Agriculturalists and Horticulturalists
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· Land use & forestry
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10. Tourism
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· Recreation & tourism
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11. Marine Resources
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· Aquaculture
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12. Health
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· Water quality issues
· Sanitation
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The components, objectives and expected outputs or outcomes of Pacific HYCOS are listed on the About Page. These stem from the objectives of the World HYCOS Project administered by the World Meteorological Organisation:
- To support regional institutions and national water resources agencies in discharging their relevant regional and national responsibilities in support of:
- Integrated water resources management (IWRM)
- Water resources assessment
- Flood forecasting and warning
- Groundwater monitoring and assessment
- Water quality monitoring
- To strengthen and build the capacity of regional institutions for cost-effective and sustainable water resources information systems and data dissemination by national water resources agencies
- To supplement existing hydrological observing programmes, especially in terms of observation networks
- To improve the quality of hydrological and related data and information by adopting international standards
- To support development, implementation and maintenance of appropriate modernized regional and national databases
- To support greater efficiency in the acquisition and dissemination of water related information, and development of regional and national water resources information systems by encouraging and facilitating cooperation among countries sharing the same water resources.
The above objectives are reflected in the following scenarios and case studies.
Disaster Risk Management
Within the context of disasters such as drought and flood hydrological data sets can provide accurate predictions based on factual trends. Currently these predictions are done using historical profiles and seasonal calendars which in theory should be based on, amongst other things, hydrological data. Unfortunately theory often does not mirror reality.
By using geographic information systems (GIS) hydrological data from several locations can quickly indicate highly vulnerable areas. Using the same method mitigation and adaptation measures can be strategically introduced such as large communal water catchments for optimum rain water harvesting during wet periods to prepare for prolonged dry spells. Another example is to use hydrological data to improve food security for specific geographic locations i.e. based on hydrological trends one can determine which areas will be affected by drought or flood and thus provide adequate warning for agricultural seedling stockpiling of flood and drought resistant crops.
Engineering
From an engineering perspective hydrological data is valuable for town planning of infrastructure and construction of buildings and structures like hydro dams.
Hydrological data can determine how much water an area receives and thus answer several questions like soil integrity i.e. is the ground stable for construction and if so what weight capacity will the ground support, horticulture and agriculture issues i.e. what plants and animals will thrive in an area, what type of material is best for building, type of roof, is it necessary to install a catchment system on buildings i.e. roof guttering and water tanks.
Hydrological data also helps determine the most appropriate drainage system for a residential or industrial area, irrigating farmland and drainage from a wetland where property and people are located which is common throughout the Pacific.
Water Consumption
Water consumption or meeting the water demands of a community is another vital reason for collecting reliable hydrological data. Know how much you receive during a certain period in any given location by various means i.e. ground water, rain water and surface water (rivers and streams), is essential to determining how much water you can supply, to whom and when. In some countries where water supply is very limited it is necessary to accurately ration water supply based on what consumers need rather than what they want.
Case Study 1
(Introduction to flood hydrology, river modelling and floodplain mapping, July 2006, HR Wallingford)
A number of major rivers in countries throughout the Pacific can be used as examples to demonstrate the importance of reliable hydrological data. The Vaisigano (Samoa), Labasa, Navua and Rewa (Fiji) rivers each drain into vast areas.
The Vaisigano river is the largest on Samoa’s main island of Upolu. The river drains directly into the capital Apia which is densely populated. Much of Apia is located on low lying area. During a deluge infrastructure such as storm water drains are unable to cope with the large capacity of water. Mean annual precipitation is recorded only for 1973 (5816mm), 1976 (4777mm) and 2001 (2994mm). River flood variability may be expressed by the standard deviation of the logarithm (base 10) of the annual maximum flood series (10). The world mean of this index is 0.28 and it is proposed that values > 0.6 are ‘catastrophic’ floods. The flood variability index for the measured data is 0.6, which is at the threshold for catastrophic flooding. The ‘near catastrophic’ flood index for the Vaisigano indicates frequent, high magnitude overbank floods related to the biennial occurrence of tropical cyclones.
Data collected at Navolau, along the Rewa river, between 1970 – 1997 during tropical cyclone events show that this site experiences a high frequency of flooding. Tropical cyclones that have the greatest impact on river flows are those that pass closest to the watershed. The centres of tropical cyclone Bebe (1972, 6711m3/s), Wally (1980, 4218m3/s), and Kina (1992/93, 6923m3/s) all tracked within 50km of the centre of the Rewa basin. Most tropical cyclones approach Fiji from the northwest. This path maximises peak flows in the Rewa by delivering precipitation in the upper portions of the watersheds before the lower reaches, thereby concentrating discharge over a shorter period of time at Navolau. Also, the gauging station is located just downstream of the Wainimala confluence where flood waves from the upper Rewa and Wainimala rivers interact constructively.
Case Study 2
The water level gauge at the Nakavu site along the Navua river has collected reliable hydrological data sets since the early 1970’s when it was first established. The station is the control site for the newly installed flood early warning system for Navua. Recent gravel extraction around Nakavu has impeded the station from collecting accurate data. Readings from the station in 2008 showed a difference of between 1.5 to 2.0 metres in the base flow level. Such a dramatic difference means the entire flood early warning system is compromised. The long term solution is to carry out hydrological studies along the Navua river and determine morphology and a more accurate picture of the extent of impact gravel extraction has on the Navua river.
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