Alaminabdo53@gmail.com

A STUDY ON THE CONTROL OF WATER FLOW AT THE NEW

SITE OF ADAMAWA STATE UNIVERSITY MUBI

By

AMINU ABDULWAHAB1,BELLO ALI GARBA,2 GUNDIRI I. ABALIS3 RAJI M. OLAYINKA4

A Project Report Submitted To Geoqinetiq Geomatics Gold Medal And Prize Advisory

Board

FROM THE DEPARTMENT OF SURVEYING AND GEOINFORMATICS FEDERAL

POLYTECHNIC MUBI, P.M.B 35, ADAMAWA STATE.

ABSTRACT. This research work is a product of a preliminary watershed Analysis for the new

virgin land of Adamawa State University, and it covers an area of approximately 650 hectares. The

purpose of the research work is to describe what is not known about the condition of the new site and

also to present a list of prioritized issues for the planners in their development of strategies for further

assessment and subsequent watershed protection and restoration. The research examines land use

history, boundary limit, direction of water flow, topology of the land, water quality, soil condition and

social and economical conditions.

As in the case of tropical countries, heavy rainfall and effect of the upstream change in land use have

caused detrimental consequences in the sedimentation. Watershed analysis is recognized presently as

the most suitable tool to manage and control the flow of water in the research area.

Furthermore, the evaluation of processes that affect ecosystem and resources in a watershed is now

being carried out by a surveying student, although, the methods to be used will differ from those of

other implementations of watershed analysis because objectives and opportunities differ. In particular,

Adamawa State University Management must take into account the full range of uses and values

present. Interagency watershed analysis to include wildlife, social and economical components in

addition to the physical and aquatic evaluations shared by other watershed analysis efforts.

Interagency watershed analysis is intended to describe process interactions, GIS approach and

ecosystem functions that shape the environment. This research work will be based primarily on the

newly acquired information. It is an exercise in data gathering and inventory. The first wave of

analysis is to show the major operational difficulties and to integrate information into or from multiple

disciplines into an interdisplinary analysis.

This research work will also focus on providing all the necessary information needed relating to the

impact of flooding within the new site. It will also provide all the necessary actions needed in the

control of flooding within this area of study so that a suitable location for dam, reservoirs will be

recommended.

Finally, GIS approach will be used in the cost of this research work, to help in the control of disasters,

erosion, irrigations and flow of water.

Key words: GIS, DEM,HRU,BMP

INTRODUCTION

Sustainable development requires coordinated, comprehensive and sustained Earth observations for

early warning, informed policies and effective decision making. In support of this objective, I intend to

put an effort in conducting a study leading a GIS approach to solve the environmental problem of the

research site. It is foreseen that these problems of future planning and the derived Products will be

distributed via Geoqinetiq Geomatics Gold Medal And Prize Advisory Board Cast to a broad range of

user communities. Therefore, an analysis of the Adamawa University new site watershed, on the

southern part of mubi in Adamawa state (fig. 1), was conducted by the student of surveying and

geoinformatics in 2009-2010. The analysis was initiated to better understanding of the precise mapping

project (GPS field campaign, georeferencing and on-screen digitization of analog topographical map at

the scale of 1:50,000, and a better documentation of the data for the benefit of the state and the nation

as a whole) was also done. Some selected ecosystem components within the watershed was also

examine. The purpose of this report is to present report on “what is not know” that was prepared for

Geoqinetiq Geomatics Gold Medal And Prize Advisory Board as analysis report. The watershed

module report is organized around the key questions for the watershed issues that were developed

through field survey, GIS and remote sensing by the researcher.

The project site formally belongs to the milk industry known as (Gidan Madara) along Sahuda

Road, but after the breakdown of the industry, the site remains vacant for more than a decade. During

the Boni Haruna regime In 2002, the state university was established which led to the cancelling,

collection and conversion of the Shuware Government Collage into its site. But due to the rapid

increase in the population of both staffs and student, brings about the demand for a new site (Sahuda

road campus) from the state government and this demand was a success.

LITERATURE REVIEW Over the years, many models have been developed to help agencies assess and control the quality of

many nation’s water bodies such as USA, UK e.t.c. Water quality simulation models have been

developed by government agencies, academic institutions, and consulting firms. Because end-of-pipe

point sources are largely controlled and are highly regulated, more and more focus is being placed on

non-point sources which make up a significant portion of pollution in natural waters. There are a large

group of non-point source models that have been developed to address water quality concerns. These

models are written in standard FORTRAN77 and are executable in the MS-DOS environment. Some of

these models have been updated to include a Windows user interface. One of the potential drawbacks to

using these models can be the need for very large input data sets. Conversely, spatial averaging can be

assumed to decrease the amount of required input data at the potential expense of output accuracy.

Some detail on these models is presented briefly. Geographic Information Systems are becoming more

useful in modeling water quality because they can incorporate spatially varying data. There are many

instances where GIS have been incorporated into modeling efforts, and two basic ways that they have

been used are: (1) as a method for deriving input for external models, and (2) as a stand-alone model.

Since water quality is integrally related to water quantity, some hydrology models will also be

mentioned in the review.

PHOTOGRAPHS ON SITE

Some of the hardware/software Used are listed

below:

24 Channel GPS receiver ( 5800)

Leveling instruments

Total station (TPS 400)

Laptop (HP Compaq 6720s)

Scanner (HP 3220)

Software

ArcView 3.2

Ilwist 3.1

Global mapper 11.0

Surfer 8

AutoCad 2009

STUDY AREA

The study area is located in Mubi south local Government area, with three conical hills inside, the site

is adjacent to the road to Cameron and it experiences a lot of smugglers along its site. Mubi lies at an

approximate latitude and longitude ’ ’’ and ’ ’’ respective y with an approximate

population of 225705 (GeoNames geographic database). The area covered by this study is

6494.2015Sqkm of land.

Fig 1. Map of Mubi Showing The Study Area.

TOPOGRAPHICAL ANALYSIS

In this study, a topographical analysis was carried out to shows or tells the distribution of details (both

natural and man-made features) on the surface of the earth within the study area. It gives information

relating to the height of points below or above the mean sea level. Fig. 2 shows the topographical map

of the project area; this map shows the distribution of details such as the man-made features (buildings,

roads e.t.c.) and natural features (trees, stream, foot paths e.t.c.). It also shows the generated contours at

1meter interval within the project area. The contour ranges from592-666m.

Fig. 2 Topographical map

METHODOLOGY Input data were composed of derived digitization and simplification methods specific to GIS

technique. All the vector data (elevation values from on screen digitization and field data) were

combined with raster (ortorectified imagery) and correlated, finally analyzing the derived

geomorphologic parameters (figure no. 3). The geomorphologic parameters (slope, aspect, elevation,

curvature of terrain and roughness) were analyzed individually and put together in a formula,

returning the risk of Water flow.. R av = (S + Ex + Al + Fx) * Rg

Digital Elevation Model A digital terrain model (DTM) , also known as a digital surface model (DSM) or digital elevation

model (DEM) is a topographic mode of the “bare earth”. All features such as vegetation, buildings,

bridges etc. are removed to create the bare earth/ DTM.

For the creation of a DEM of the area under examination, 491 x-y-z vector points data, taken from the

field, the topographical map was scanned and converted to raster images using ILWIST 3.1 Academic

software and the satellite image of the Area was also acquired. An example of x-y-z point data and

generated DEM is given in Figure 4.

Figure 4. DEM

Extraction of river network From the accumulated drainage area map the river network can automatically be extracted. a constant

drainage area threshold at

was used for this purpose. Every cell that has a > at was defined as a river

cell. As can be seen in slope/aspect map in Figure 7, the extracted river Network depends from the

chosen drainage area threshold at. The smaller you choose a

t , the more branched is the river network.

The bigger you choose the threshold value the less branched is your river network because fewer cells

are larger than the threshold used to define river cells.

Fig. 5 DEM SHOWING TERRAIN ROUGHNESS

VECTOR MAP The vector map of the study area was generated using the Surfer 8 software to show direction and

magnitude of data at points on a map, this vector map shows the natural flood direction within the study

area and it was overlay on the terrain roughness. You can create vector maps from information in one

grid or two separate grids. The two components of the vector map, direction and magnitude, was

automatically generated from a single grid by computing the gradient of the represented surface. At any

given grid node, the direction of the arrow points in the direction of the steepest descent. The

magnitude of the arrow changes depending on the steepness of the descent. Two-grid vector maps use

two separate grid files to determine the vector direction and magnitude. The grids can contain Cartesian

or polar data. With Cartesian data, one grid consists of X component data and the other grid consists of

Y component data. The Overlay of vector maps on 3D surface maps was done to enhance the

presentation.

Fig. 6 vector map on DTM

Reference Vectors

0.00054725744701830.27579776067613

TERRAIN PARAMETERS

Slope is between one of the most important geomorphometric parameters of terrain surface,

representing an important role in determining the geomorphologic processes that affect a certain area. It

represents the quantitative measure of maximal change of elevation values (Shary et. al., 2002), ranging

from 0° to 90°. Base on the DEM of the study area, it can be seen that it is flowing towards the NE, i.e

to the blue Zone.

Geometrically, slope describes the angle between the horizontal plane and the tangential to the surface

and slope is expressed as follows:

Slope gradient can be expressed in either degrees or radians, but more commonly Percentages are used

to refer to slope values (tan (S) *100).

Fig7. Slope map (Left) in Ilwist 3.1 and Aspect map (Right) in Arcview 3.2

A survey of water available for runoff of a single storm would consist of measurements to compute

water available for runoff at several different sites that vary with respect to altitude, vegetation type, or

aspect direction. The erosion pack low-water equivalent would be measured before and after the storm,

as would the amount of water from the higher surface or bare soil (lower) surface during the storm.

Total storm water available for runoff at each site was then computed from an equation for the site

water balance. An equation for the water balance is

where

WA

R

is the total water available for runoff

for the storm, in meters;

P is the quantity of water from higher that

is input to the high or low soil surface

during the storm, in meter;

ΔSW

E

is the change of higher part water

equivalent during of the storm, in

meter; and

E is the total evaporative loss during the

storm, in. meter;

Another parameter is represented by aspect which represents a crucial role in a number of

morphological, hydrological and ecological processes. It is defined as the compass direction to which a

slope faces, measured in degrees from North in a clockwise direction and ranging from 0° to 360°.

Aspect can be defined as (Shary et.al., 2002):

As seen in figure no. 6, the west, North-West and North-East versants are the most representative due

to the fact that the rapid downhill flow of a large amount of water risk is higher in those areas.

IMAGES As basic image layer for the terrain model, orthoimages with 6.91×6.96 m image resolution of the study

area was taken from the internet using the Google earth 5.3 software. The images were georeferenced

in both Global Mapper 11.0 and Ilwist 3.1 software presented in Figure 7 below. The map on the right

blow shows the contour of the study area being overlaid on the satellite image, the blue portion of the

map indicates the recommended site for future DAM construction generated Arcview.

Fig7. Recommended dam site (Left) in Arcview 3.2 and boundary on image (Right) in Global Mapper

v.11

PROFILE Profile curvature is the curvature of a line formed by the intersection of a fictional vertical plane with

the ground surface. While a zero value of profile curvature indicates a flat surface, negative values

indicate that the surface is upwardly concave and positive values indicate that the surface is upwardly

convex. Profile curvature can be determined using the following calculation formula (Evans

1972, quoted by Shary et. al., 2002):

Nonetheless landform is very useful for Water flow risk because it determines the possible water

accumulation area or the possible areas of propagation. The concave areas are mostly represented by

the bed’s rivers. The convex one’s in genera are represented by the highest s ope va ues.

The profile along the major flow channel was generated with the Global Mapper 11.0 so as to

graphically visualize the terrain within the valley or concave areas of the site as shown fig 8 below.

Fig. 8 Profile along the steeply area from DEM

Geology and Soils

The geology of the watershed affects hydrologic responses in the watershed insofar as it controls bed

surface slopes and gradients in stream channels and as it affects substrate materials that control or

mediate subsurface flow. Ridges within the North, Middle and South sub watersheds are composed of

rocks of sedimentary origin, such as sandstone and shale (Tabor and Cady, 1978). The sides of the

ridges are very steep. As a result, the hydrologic response to storms of many smaller, steep-gradient

tributaries is prompt.

HYDROLOGICAL RESPONSE UNITS (HRU) Definition For rainfall-runoff modeling the watershed may be divided into areas that have a similar hydrological

response, that is based on their physical characteristics (such as soil type, vegetation, slope, etc.) they

may have a similar response to a unit input of rainfall. This is the theory behind defining HRUs, i.e.

hydrological response units.

In this part of the study, HRUs for the new site was defined.

Steps in defining HRUs Since the new site is in a steep Alpine environment, I expect that slope may play an important role in

runoff production. For this reason slope, aspect and overlays was used as the primary factor and the

proposed land use design as the secondary factor for HRU definition. 3 different slope category groups

were determined using the arcview 3.2:

1. Highs slope between (33.728 - 37.944) °

2. Medium slopes between (16.864 - 21.08) °

3. Lower slopes (0 - 4.216) °

Category group 2 subdivided in 9 land use category groups:

Residential, recreational, student res, commercial, Green, academic, parking, administrative and others

This division resulted in 9 HRUs of land use which are show in Figure 9.

Fig 9 Land Use Map Of The Study Area

The main properties are listed in Table below.

S/NO USES Area(m2) 1 residential 1908232

2 recreational 824383.8

3 student res 659122.1

4 commercial 403703.1

5 Green 448696.1

6 academic 1082357

7 parking 51628.61

8 administrative 61575.22

9 others 1051491

total 6491190

The reason why I took the slope as primary factor is, that I think it is a major parameter for runoff modeling

and we just want to use these HRU therefore. Further, the subdivision by land use seemed to be possible for

me because of the obvious influence on runoff.

TABLE OF DATA

The table below will show the field vector data obtained with both 24 channel GPS and TPS 400 Total

Station instrument.

KEY HYDROLOGY ISSUES AND KEY QUESTIONS

A. Maintaining flows in the Study area and its tributaries that are, to the degree possible,

beneficial to human uses and that promote maintenance or restoration of critical ecosystem

functions; and

B. Effects of management on wetland form and function.

These issues were addressed through a key-question process, which is the principal vehicle

prescribed by GIS Applications and Guide for advancing through watershed analysis. The key

questions are:

1. What are the natural, physical, and biological features of the watershed that control hydrologic

responses?

2. What is known about current stream flow characteristics, including peak and low flows?

3. What evidence exists that forest harvesting and road construction have altered frequency and

magnitude of peak and low flows?

4. What is currently known about the distribution and extent of wetlands, and what have been the

impacts of land management activities on wetlands?

5. How might existing hydrologic monitoring be maintained or augmented to help detect future

hydrologic change, to preserve critical ecosystem functions, and to protect public and private

property?

The key questions were researched using the scientific literature, a brief field investigation, and

hydrologic, climatic, and resource mapping databases created and maintained by the researcher.

RESPONSES TO KEY QUESTIONS

For this report, hydrologic response is defined as a change in a hydrologic variable as a result of

changes in rates at which water is added to or taken away from a hydrologic system. Hydrologic

variables include stream flow, overland flow rate, water yield, stream and lake stage, hydraulic head,

hydraulic gradient, ground-water recharge and discharge, evaporation, transpiration, ground-water flow

rate, and soil water content.

Climate

Variations of weather and climate are probably the most important determinants of hydrologic

responses in most watersheds. Weather refers to meteorological conditions, such as precipitation

or air temperature, as they occur at any given instant, and climate refers to the average weather

conditions or to recurrent seasonal weather variations during some number of years

Vegetation performs a number of functions that can influence hydrologic responses. First,

terrestrial vegetation mediates the exchange of water and energy between the atmosphere and the

soil and thereby exerts control on the amount of water that is stored in the soil and available to

recharge streams or ground water. For example, vascular plants can absorb water from the soil

through their roots and transport it to their leaves, where the receipt of energy from the atmosphere

causes the water to evaporate. The nature of the leaf surface, such as how efficiently it absorbs

down welling solar radiation, in part determines the magnitude of evaporation and, ultimately, the

amount of water withdrawn from the soil. During rainfall, some of the precipitation is intercepted

and stored on the surfaces of the vegetation. Some of the intercepted water can drip from the

vegetation to the soil, and some of the water evaporates into the atmosphere. The process by which

water evaporates from wetted vegetation is termed "interception loss." In some situations, the

presence of vegetation can lead to increased inputs of water to the soil surface. Vegetation can

intercept some of the moisture from fog and some of that intercepted moisture can drip onto the

soil surface.

RESULTS Finally, all the geomorphologic parameters were analyzed together. The study area (650 hectares) was

divided in 450 cells with a resolution of 6.91×6.96 meters. Every cell risk coefficient was

independently obtained by entering the specific parameters of that area in the final formula. A class of

values of Risk of avalanche was established. Finally, for each cell I obtained values varying from 0 to

12.71.

Summary This study and model do provide an effective, scientifically based management tool despite the

limitations of the model and the need for more data. The current model calculates flowed based on

acquired field data. Loads from individual watersheds were quantified, and the effects of various BMP

implementation strategies were examined to help focus those efforts. This tool allows managers,

planner, Architecture, surveyors and engineers to quantify load contribution, not only on a sub-

watershed basis, but also on a land use basis within sub-watersheds. The decision support system

developed in this project is merely a starting point. It is intended to be a living model. It provides a

framework for developing a more detailed tool to be used by managers and stakeholders in the

Adamawa state new site watershed. As monitoring and data collection continues, the model can be

updated to allow for more specificity and detail in the analysis. This model refinement will not happen

overnight, but as more data becomes available, it can be used to provide more focused guidance for

resource managers.

CONCLUSIONS This study demonstrates that GIS is an effective platform for modeling water Quantity and quality in

the Adamawa state new site watershed and for developing a decision support system for resource

managers. Loadings from the basin sub-watersheds are segregated and attributed to various land uses

are described. The experiment was tested and the results confirmed the risk of water flowed to be

present in most of the land uses due to the nature of the terrain .The final results were compared with

the background from the “terrain” the vector and the raster data confirmed the potential areas which

were in a 90 % accurate. The current mapping project could represent a base for land planning and

utilization, a method for prevention, maybe a future interactive web mapping, a useful tool for the

Management of risk sites and can be applied in different areas and has an educational goal.

REFERENCES Andreea.Argesanu, (2009):The Role of Geomorphometric Characteristics in Mapping

Avalanche Tracks, Case Study: Valea Cerbului, Bucegi Mountains –Romania

Kingston University, London,

Autodesk (2009): Autodesk AutoCAD 2009. Online resources:

http://www.autodesk.com

Dartiguenave, C., (1997): Water Quality Master Planning for Austin. Master’s Thesis The

University of Texas at Austin, Austin, Texas.

Irina Ungureanu,( 2000): Geografia Carpaţilor şi Subcarpaţilor, curs, Biblioteca

Universitară Iaşi

I., Bojoi, Geografia fizică a României, Editura Universităţii A.I.Cuza, Iaşi,

S. Fuchs, M. Bründl and J. Stötter, (2004): Development of avalanche risk between

1950 and 2000 in the Municipality of Davos, Switzerland, Natural Hazards and

Earth System Sciences, 4, 263–275

M. Keiler, R. Sailer, P. Jörg, C.Weber, S. Fuchs, A. Zischg and S. Sauermoser, (2006):

Avalanche risk assessment – a multi-temporal approach, results from Galtür,

Austria, Natural Hazards and Earth System Sciences, 6, 637–651

Metcalf & Eddy, Inc, 1991. Wastewater Engineering: Treatment, Disposal, and Reuse.

Edited by G. Tchobanoglous and F.L. Burton, 3rd Edition, McGraw-Hill, Inc.

New York.

Mitchell, J.K., B.A. Engel, R. Srinivasan, and S.S.Y. Wang, 1993. Validaation of AGNPS

for Small Watersheds Using an Integrated AGNPS/GIS System. Water Resources

Bulletin, 29 (5):833-842.

Riggs, H.C., 1972, Low-flow investigations: U.S. Geological Survey Techniques of Water-Resources

Investigations, Book 4, chap. B1,18 p.

Rothacher, J., 1965, Streamflow from small watersheds on the western slope of the Cascade Range of

Oregon: Water Resources Research, v. 1, p. 125-134.

S. P. Pudasaini and Kolumban Hutter(2007): Avalanche Dynamics: Dynamics of

Rapid Flows of Dense Granular Avalanches, Springer, Berlin, New York,