Based on the drainage system, the Chindwin catchment was divided into 57 subbasins, as shown in Fig. 4a. The sizes of the basins ranged from 3 km2 to 11,762 km2. The minimum elevation of the basins was 69 m above mean sea level in the central flat plain, whereas the maximum elevation was close to 1,800 m in the mountainous regions. Average slopes of the basins varied from 0.7% to 16.4%, while the basin lengths were between 2 km and 397 km. Shape factors range from 1.3 to 13.4 as different-sized basins constitute the entire catchment. With a narrow and elongated shape, basin 24 has the biggest shape factor and area because it represents the catchment area of the largest tributary of the Chindwin River, flowing from north to south. Tc values for each basin varied from 9 minutes to 1138 minutes, according to the orientation of the basins.
In the CN calculation, only three hydrologic soil groups (B, C and D) were found in the Chindwin catchment. Hence the parent geological material of the watershed may have a range of water transmission rates between 0 to 8 mm/h according to USDA (1986). Although the infiltration rate of the soil depends on the depth of impermeable layers, it can be generally said that the catchment has low to moderate infiltration rates. Group A soil, which mostly consists of excessively drained sand or gravel, was not found in the catchment. As shown in Fig. 4b, the CN values ranged from 58 (lower runoff) to 100 (higher runoff) across the catchment. The results show that the Chindwin territory has three distinct divisions. The areas with lower CN values (55-65) were found in the upper and northeastern parts of the catchment. The middle and southwestern parts have moderate CN values (65-80) while the lowest region sh...
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...e to the low rainfall. However, the extreme climatic effects from its upstream part may superimpose on flooding in it.
In Cluster 3, the mountainous regions are dominant with higher mean basin elevation of 1344 m accompanied by higher basin slopes (3.4% to 16.4%). The region, which mainly covers the most upstream parts of the Chindwin catchment to 85 km downstream Hkamti station, receives the highest mean annual rainfall of 3000 mm, and can generate moderate to higher runoff with mean basin CN of 81. Therefore, the region can be regarded as the highest flood potential zone compared to the other clusters.
With a mean basin elevation of 470 m, the highland region on the right side of the Chindwin mainstream constitutes the majority of Cluster 4. The region is characterized by a moderate annual precipitation of 2000 mm and has a moderate runoff potential with CN of 74.
As can be seen from the photo( Image 1), looking downstream, there were steep sections of bank where it appeared the erosive forces of the river when high have cause part of the bank to fall away leaving steep about 1m high drops on the bank with exposed rocky soil visible. The phenomenon also illustrate that it is an alluvial landforms, which will find erosional feature from fluvial
Moore, J. R., Bell, A. V., Jones, A. D., 2005. Forecasting for flood warning. C.R Geoscience 337, 203-217.
The study site included four lakes in the Yahara chain: Mendota, Monona, Waubesa and Kegonsa. The Lake Mendota is the largest and deepest of all 4 lakes, it has an influent derivative from agricultural and urban sources. The influent for Lake Monona is urban and it is the second largest and deepest lake. For Lake Waubesa, that is the smallest and less deep lake, the influent is from urban and agricultural. And for the last lake, Lake Kegonsa, has an agricultural influent and it is really shallow. For the modeling the scheme was in the same order, first Lake Mendota, then in the chain Lake Monona, in third place Lake Waubesa and at the final of the chain Lake Kegonsa.
river basins that flow into it transporting TN and TP from the outfalls of terrestrial wastewater
Within a river there are areas known as pools and riffles. The pool is an area of deeper slow moving water, whereas the river is an area of shallow, fast flowing white water. The rocks are also clearly visible at the riffle, but submerged in the pool. A pool is usually found on a meander whereas the riffle is normally seen on the straighter areas of the channel, they tend to be situated very close to one another, forming in sequences. The aim of this investigation is to carry out a field investigation at a pool and riffle and compare the characteristics at these two sites with the objective to state the differences.
Since there is semi-arid climate, there is low and unreliable rainfall. Mean annual rainfall in North China is only 400-500mm, but mean annual evaporation reaches 1500mm in China, resulting in water deficit.
Most of water consumed in China is not rationally used. The cause which intensifies the water shortage in China is water inefficient use. For instance, 65%-70% of Chinese water usage is spent on agricultural needs, but more than half of this amount evaporates percolates and loses (Roberts 2009). Besides, majority of another 20%-25% which is occupied by China’s industry is not recycled (Brown 2008a, 16; Roberts 2009). Obviously, improving water distribution technologies and management quality can be one of the options to reduce the water scarcity in China. There are many different methods of improving the water distribution efficiency. Firstly, irrigation technologies should be improved. Farmers in China may use drip and shrink irrigation methods instead of traditional “surface” ones such as furrow and flood irrigation. Drip irrigation method is used mostly in arid and semi-arid zones and it increases the efficiency of irrigation by transporting the water directly to the roots of irrigated plant. The emitters sprinkle the soil under the roots with water which is introduced to the plant by pipes, diminishing water evaporation, deep percolation and leak. In contrast, fur...
Aim: To determine what effect agricultural runoff has on surrounding environment, and to find what solutions can be made to reverse any damage.
The water moves at a faster rate since there is nothing to absorb the water, which could cause flooding.
...f the streams and drainage basins were found using the Calculate Geometry tool in ArcMap. This information gave us the minimum, maximum, average, and total stream lengths, along with the area of the drainage basins. Once this information was obtained it was used to calculate morphometric relationships (table 1). The sinuosity of the BRV was determined through a custom built tool in ArcMap that took the length of the stream over the length of the valley.
The Three Gorges Dam in China is the largest hydroelectric dam ever built. The Three Gorges Dam (TGD) was built to prevent flooding, as well as produce energy. Flooding has plagued the Yangtze for centuries; Chinese authorities estimate that some 300,000 people were killed in the 20th century's largest Yangtze River floods. In 2012 during the peak flood season, with a peak flow of 70,000 cubic meters of water per second (Angela), the TGD performed as expected controlling the floodwaters, from flooding the Yangtze saving thousands of lives. Production of power has been as inclusive as preventing flooding, “the hydropower produced by the TGD will supply only produce 3% of Chinas energy needs (originally assumed to supply 10%, however the rise in population and demand, has decreased it to 3%.) The hydroelectric power will save energy needed to mine, wash and transport coal from northern China”(Angela).
Because watersheds are specified by natural hydrology they represent the most logical basis for managing water resources. The resource becomes the center point and managers are able to gain a more complete understanding of overall conditions in an area
...creased rainfall and increased temperature in the western part of Central Asia such as Uzbekistan and Turkmenistan leading to the scarcity of water which directly heats the agriculture and livestock production. The estimating consequences from the precipitation and temperature change on the production of food are the potential changes in variability and extreme events like droughts, heat waves, sand storms and heavy rainfall. Increased surface runoff in the mountainous regions accelerates the land slides, soil erosion and floods which have huge capability to destroy the crops.
Flooding is an ongoing challenge in regional Victoria and it is expected to affect Victoria every 10-20 years. Victoria consists of 39 drainage basins and each of the basins comprises of rivers and streams (Comrie, 2011, pp.17). These rivers and streams are susceptible to flooding, which may impact various regional towns and communities within close proximity to water courses (Comrie, 2011, pp.17). The discussion of flooding is vital, as it is the most frequent occurring natural hazard, which affects approximately 520 million people per year Moore et al.2012, pp.1). Additionally, flooding is responsible for the lives of approximately 25,000 people every year and cost the global economy approximately $50- 60 billion per year (Moore et al.2012,
...eport also documents all the research which has been scheduled for the area as well as the researchers who are planned to come in. This report also provides some suggestions as to how the river can be rehabilitated. This is source is valid and reliable to some degree because it is written by Ian Garland himself, and he has seen all the changes in the area but as he is a conservationist and because he has an attachment to the area, this report will contain bias. The element of bias can also be a limitation because the report was done to highlight the state of degradation that the rivers were in. This information is valuable to proving the hypothesis regarding the relationship between catchment management plans and the present state of the Siyaya Estuary as it allows a comparison to take place to compare the descriptions of the rivers to the present day conditions.