Inland Waterways Design Criteria and its Applications in ...iwtc.info/2005_pdf/13-2.pdf · Ninth...

Ninth International Water Technology Conference, IWTC9 2005, Sharm El-Sheikh, Egypt 905

INLAND WATERWAYS DESIGN CRITERIA AND

ITS APPLICATIONS IN EGYPT

Hossam El-Sersawy * and A.F. Ahmed **�

* Doctor, Researcher, Nile Research Institute (NRI), National Water Research Center (NWRC), Egypt

E-mail: [email protected]

** Professor, Director of Nile Research Institute (NRI), National Water Research Center (NWRC), Egypt

E-mail : [email protected] ABSTRACT As the Nile River and its branched streams were formally assigned for irrigation and water supply, development of the waterway transport system becomes necessary. Improvements of the inland navigation system in Egypt to fulfill the required safety measures are being considered. Inland navigation is the safest, cheapest, tourist attractions and the most environment friendly means. The present study is carried out to illustrate the methodologies for designing the navigable channel dimensions for the first class navigation waterways in Egypt. The available data of the numbers, dimensions, status and types of ships used in different stretches are utilized to determine the representative ship dimensions such as draught, beam, and length relative to each type of inland waterway are assigned. The design ship dimensions are utilized to illustrate the suitable waterway width for the different first class navigation waterway in Egypt. Four design methodologies for the navigation channels are presented which produce suitable guidelines to be applied for the first class inland waterways in Egypt. The first two approaches were empirically developed to determine waterway width in each of one and two way traffics of straight channels. While the other two methods, are commonly used and applied for straight and curved waterways. These approaches were applied on the Nile River, Damietta branch, Rayah El-Behery and El-Nubaria Canal. The results are obtained for the navigation channel widths and are compared for each of the mentioned design methods. Key Words: River Nile, Inland Waterways, Navigation Channel, Design Criteria, Damietta Branch, Rayah El-Behery and El-Nubaria Canal.


INTRODUCTION The evaluation of the characteristics of the existing natural streams should be the first step for waterway planning. It is obvious that the first class inland waterways in Egypt are mainly natural streams. The design of such waterway channel in natural streams should involve many factors such as the channel widths and depths at various seasons, sediment transport load, extend of bank erosion, flood magnitude and frequencies, environmental considerations, size of locks; berths; and docking facilities available, visibility, bridge locations and clearances, weather conditions, and different topographic and hydrographic characteristics of the stream. In addition, the type and degree of waterways, and the available data for physical ship dimensions should be taken into consideration. One of the objectives of the Ministry of Water Resources and Irrigation provides save, and effective navigation channel in the Nile River and its branches. According to the data from RTA (River Transport Authority), it shows that more than 2.9 million tons of cargo were transported per year which represent only 20% of the waterways navigation capacity. The present study is carried out to illustrate the modern techniques and latest technologies with the comprising of the “Permanent International Association of Navigation Secretariat (PIANC)” and “International Association of Ports and Harbors (IAPH)” approaches to determine the suitable dimensions of the first class waterways in Egypt. The available data of the numbers, dimensions, status and types of ships used in different stretches are examined to determine the suitable waterway width. Four methodologies for the design of the navigable channels are presented which give a suitable guideline to be applied for the first class inland waterways in Egypt. The first two approaches were empirically developed to determine waterway width in each of one and two way traffics of straight channels. While the other two methods, are commonly used and applied for straight and curved waterways by taking into consideration some governing factors. The application is carried out to determine the channel width by the presented four methods for the River Nile, Damietta branch, El-Behary Rayah, and El-Nubaria canal. The results are compared for each of the mentioned design methods to get good control, safe maneuvering, and economic navigation. OBJECTIVES The aims of the present study are:

1- Evaluate the suitable dimensions of the first class waterways in Egypt. 2- Compare the methodologies for the design of the navigable channels width. 3- Develop suitable guidelines and procedures to be applied for the design of the

inland waterways in Egypt.


INLAND WATERWAYS IN EGYPT In a recent classification (1999) the River Transport Authority (RTA) divided the waterways in Egypt into three classes depending on the criteria listed in table 1.

Table 1. Inland waterways classes in Egypt

First class Criteria The Nile Main canals Second

class Third class

Minimum Clearance below structures (bridges) (m) 13 6 3.5 2.5

Minimum Navigation vent width (m) 35 12 8 Maximum draft (m)� 1.8 1.5 1 Minimum water depth (m) 2.5 1.8 1.25 Total length (km)� 2191 121 813

All these navigation routes in upper and north of Egypt are shown in Figure 1. Concerning the first class inland waterways in Egypt, Sabet et al. (2004), divided the first class navigation routes into four main stretches depend on the traffic intensity and type of transported production, the following four reaches can be justified: 1- The reach between Aswan and Luxor is 216.0 Km long and mainly used by tourist

floating hotels with heavy traffic density of more than 5 units per hour. While the traffic density of the other types of navigation units can be neglected as it is limited to less than 2 units per hour.

2- The reach between Luxor and Cairo is 704.0 Km long and mainly used by pusher

Figure 1. The Navigation Routes in Egypt (Source M. Elzeir, 2002)


barge and pushed dump barge units with heavy traffic density while the traffic density of the floating hotel units can be neglected.

3- The navigation waterway along Damietta Branch is about 227.25 Km long and

mainly used for transportation of goods and row materials by different types of navigation units of which pusher barge and pushed dump barge type is the majority. On the other hand, this waterway can be considered as the most important transportation path between Cairo and the outer exposed waterway to the open sea at Damietta and Raas El-Barr harbors. It is believed that the development activities for the navigation waterway - which are being carried out by RTA (River transportation Authority) in this branch - will lead to improve the traffic density to more than 5 units per hours.

4- The transportation waterway along El-Behary Rayah and El-Nubaria Canal can be

considered as the most important navigation waterway between Cairo and the outer exposed waterway to open sea at El-Dekhala and Alexandria harbors. This waterway is about 202 Km long of which 82 Km along El-Behary Rayah, then 100 Km along El-Nubaria canal then ended by about 20 Km across Marriott Lake till the open sea.

It is obvious that each of the above four reaches has specific characteristics and function within the Egyptian waterway system and consequently the design criterion and traffic considerations of each waterway channel will be varied from one reach to other. METHODOLOGY Natural Streams Consideration The types of waterways in Egypt normally are nature streams. The existence of some morphological changes in the river such as bank failure, bed degradation, island formation, etc.; increase the interest towards sediment transport. The movement of sediment in natural streams is extremely complex depending on many factors, most of which are interrelated. Solution of sedimentation problems requires knowledge of the general characteristics of the stream and of the principles of river sedimentation processes. Natural streams tend to meander, developing a sinuous course (Figure 2a). The degree of sinuosity assumed by these streams depends on many factors including discharge, sediment load, valley slope, and composition of bed and banks. Because of the concentration of high velocity currents and turbulence in bends, much more sediment can be moved in sinuous channels than can be moved in straight channels with the same average velocity and slope. For this reason, straight channels and crossings downstream of a bend will tend to be shallow and unstable. Because of the reduced slopes and velocity, deposition is seldom sufficient to reduce depths to less than the required depth for navigation. The channel in bends tends to deepen during high river stages.


The main causes of shoaling problems are, changes in the discharge and stages produce changes in currents and in the movement of sediment. The investigations have indicated how channel depth and configurations can be altered with changes in stages. The movement of sediment in one reach can be considerably higher than in a reach just downstream during low flows and considerably lower during high flows (figure 2.e). in addition, changes in low water slope profiles are usually indications of the relative amount of sediment movement in successive reaches. When the low water slope in a reach is substantially higher than the average, it is generally an indication that more sediment was moved into that reach from upstream during the higher flows than could be moved through the reach during the same and subsequent flows. Unstable and trouble some reaches will trend to have a higher than average low water slope as shown in figure (2.d). Design Requirements 1. Channel Width As no specified criterion was set for waterway channel design, certain recommendations were made by the national and international authorities, which were modified later. Among these are the Permanent International Association of Navigation Congresses "PIANC", the International Association of Ports and Harbors "IAPH", and US Army Engineers. Consequently, the following design factors for waterway channel were considered:

1- Dimensions of the largest ships, considering their lengths, widths, drafts, and displacements as well as stopping distances, maneuvering characteristic,

Figure 2. Characteristics of a river reach (after Fenwick, 1969)�


anchoring and mooring equipment. 2- Depth of channels, underkeel clearance, allowances for vessel motion, side

slope effects and inaccuracies in dredging and measurements. 3- Waterway channel layout, turns, and anchorage. 4- Widths for passing, maneuvering, turning circles. 5- Navigation aids and communications along the waterway channel.

2. Channel Depth Additionally, there are many factors that affect the depth of waterway navigation channel in planning and design. Those can be assigned as follows:

1- Draft of the design ship 2- Variation of river flow and elevation 3- Vertical motion of ship caused by waves, swells, squat. 4- Accuracy of measurements of water depth corresponding to ship draft and

vertical motion. 5- Allowances for sedimentation, shoaling. 6- Wind set – up, pushing water into or out from a harbor or bay.

Physical Characteristics of Ships in Egypt Development of inland waterways for navigation is usually justified on the basis of commercial traffic. Therefore, the type of vessels, equipment that would use the waterway and their principal characteristics should be considered for the design of waterway. Concerning first class waterway navigation in Egypt, the pusher barge and pushed dump barge and tourist floating hotels are the majority. With this in mind the obtained data from RTA about the total navigation ships can be classified as shown in Table 2.

Table 2. Navigation Units in Egypt

No. Division Total Number

1 2 3 4 5 6

River Transport Company Water Transport Company Sugar Refining Factory Private Sector Public Sector Governmental Units

240 216 191

4418 256 325

Total Number of Units 5646 On the other hand, the classification of floating tourist units information which are obtained from RTA are shown in Table 3.


Table 3. Physical Dimensions of Tourist Ships in Egypt

Min. Max. Type of Tourist Ship� Classified element

Total number of floating hotels =218

Ship length (m) Ship beam (m) Ship draught (m) Ship Height (m) Number of passengers

27.0 5.6

0.65 1.8 20

109.0 16.2 2.34 8.50 239

Total number of restaurant ships =16

Ship length (m) Ship beam (m) Ship draught (m) Ship Height (m)

29.0 7.0 1.1 1.6

70.5 12.0 1.5 3.8

However, it is essential - in some cases - to consider one or more other criteria for the design ship such as poor inherent maneuverability, excessive area subjected to wind, and particularly hazardous cargo. The resulted elements of the design ship for the Main River Nile and Navigation Canals are shown on table 4.

Table 4. Main Elements of the Design Ship

Design Dimensions

No.

Design Element River Nile (m)

Main Canals

(m)

Damietta Branch

(m) 1 2 3 4

The designed ship length The designed ship beam The designed ship draught The flow water depth

100.0 15.0 1.8 2.3

51.0 7.5 1.8 2.3

51.0 7.5 1.8 2.3

It is obvious that such results should be based on an extensive investigation and special analysis for the existing situation of the type, number, and dimensions of the used ships in the first class waterways in Egypt. Therefore, due to the lack of data required, the depicted dimensions in Table 4 will be used to illustrate the design procedure in the following sections of the paper. Inland Waterway Design Approaches The four design approaches for the navigation waterway are presented and applied to determine the navigable channel width for each of the River Nile, Damietta branch, El-Behery Rayah, and El-Nubaria canal respectively. The first two approaches were empirically formed in such a way as to provide safe inland navigation, which were


presented in the Handbook of Coastal and Ocean Engineering [5]. Those two approaches were mainly developed to suit the conditions through a straight waterway reaches and can be empirically determined as a multiple of the design ship width. The third approach is commonly used in the Netherlands, and is applicable for still water canal cross section, then the necessary modifications to suit the existing condition are developed. Three different increments to the calculated still water width are determined to justify the effect of cross winds, channel bends, and flow velocity. Therefore, the final designed width of the navigation channel is conveniently expressed as a multiple of the beam of the representative design ship. Additionally, the fourth method is presented, in which the developed two main equations are provided to calculate the waterway width in either of the single or two way channels as a multiple of the beam of the design ship. The radius of curvature at the bend in this method is expressed as a multiple of its length, while the depth of the channel is related to ship draught. 1. The First Design Approach This approach was empirically developed by McAleer et al. [8] for the design of one and two way navigation waterways. The approach was developed on the assumption that the navigation is easiest in a straight channel and the waterway should be made up of several segments of linked straight lines by such circle arcs. The [8] radius of these arcs should be at least equal to five times the length of the ship, but a greater radius have to be chosen where the ship is subject to cross winds or currents liable to bring about an important drift.

Figure 3. Two-Way Channel Alignment

In the case of two-way traffic waterway channel, as shown in Figure 3, the following recommendations were worked out: The waterway is fully restricted channel, Material beyond waterway channel boundary is silt, Strength of the flow currents is about 4 knots and parallel with the channel, Vessel maneuverability and controlling is satisfactory. The normal cruising speed in this waterway is 5 knots relative to the


channel bottom (One knot = 0.515 m/s), Strong winds are rare and frequently occur with certain angle to the channel. Considering that, the waterway channel in each of the River Nile, Damietta branch, El-Behery Rayah, and El-Nubaria canal is two-way traffic, the corresponding channel widths were calculated by the first approach as shown in Table 5.

Table 5. Channel Width by the First Approach

The First Class Waterway Design Element River Nile Damietta

Branch El-Behery

Rayah El-Nubaria

Canal Traffic Type Design Ship Width[Bs] Lane Width Lane Clearance Bank Clearance Channel Width

Two-Way 15.0

1.8 Bs 1.5 Bs 1 Bs

7.6 Bs

Two-Way 7.5

1.8 Bs 1.5 Bs 1 Bs

7.6 Bs

Two-Way 7.5

1.8 Bs 1.5 Bs 1 Bs

7.6 Bs

Two-Way 7.5

1.8 Bs 1.5 Bs 1 Bs

7.6 Bs Waterway Width (m) 114.0 57.0 57.0 57.0

2. The Second Design Approach It has developed by Wicker [10 and 11]. The channel width in this approach was empirically formed as a multiple of the design ship width by considering some outer effects such as the yawing forces and ship controllability. The approach was developed for one and two ways traffics and stated that the channel width should be measured at the bottom of two side slopes or at the required design depth for safe navigation. The design waterway channel width is usually determined according to the following information: Design Width = f{vessel size, vessel steering characteristics, traffic density, vessel speed, water depth, channel type, flow currents, waves and winds}

Figure 4. Two-Way Traffic Elements


This approach revealed that the first step for the design of waterway width is determining the required width of the maneuvering lane. This was defined as shown in Figure 4 as the channel within which the ship may easily maneuver without encroaching on the safe bank clearance or without approaching another ship too closely. It is likely that a lane width must be large enough to secure safe navigation. Therefore, the channel width for each of the four major waterways was determined as shown in Table 6. It is calculated depending on the designed ship width (the beam) which was assigned relevant to each of the first class waterway channels in Egypt as listed in Table 4.

Table 6. Estimated First Class Waterway Widths by second approach

The First Class Waterway Design Elements River Nile Damietta

Branch El-Behery

Rayah El-Nubaria

Canal Traffic Type Design Ship Width [Bs] Lane Width Lane Clearance Bank Clearance Channel Width

Two-Way 15.0

2.0 Bs 1.5 Bs 1 Bs 8 Bs

Two-Way 7.5

2.0 Bs 1.5 Bs 1 Bs 8 Bs

Two-Way 7.5

2.0 Bs 1.5 Bs 1 Bs 8 Bs

Two-Way 7.5

2.0 Bs 1.5 Bs 1 Bs 8 Bs

Waterway Width (m) 120.0 60.0 60.0 60.0 3. The Third Design Approach The third approach [1] is commonly used in the Netherlands and is applicable for still water canal cross section but the necessary modifications to suit the existing condition are developed. Three different increments for the calculated still water width are carried out to justify the effect of cross winds, channel bends and flow velocity. This method is based on the assumption that the navigation channel is expected to satisfy the following four requirements, first the waterway should be deep enough to ensure good steering and control of the ships in shallow water in such a way as to prevent grounding, second, the waterway should be sufficiently wide to enable the standard traffic flow to pass safely at normal speed, third, the ship should be able to reach a reasonable speed to reduce the transportation costs, finally, the navigation cross section should not be too large which reduces the flow velocity and causes sediment deposition, and would, of coarse, be uneconomical. The available information about the dimensions of the representative designed ship and the characteristics of the navigation channels were provided step by step in order to determine the final width of the required navigation channel. The design width of the navigation channel can be estimated as the sum of the navigation channel width of still water at keel level and the widths increase due to the effect of cross winds, bends


and flow currents. Those three values will be added as functions of the ship beam. In order to justify the fulfillment of the presented methodology, the developed procedure to design the navigation channel width for the channel width for the main River Nile, Damietta branch, El-Behery Rayah and El-Nubaria canal are presented as shown in Table 7.

Table 7. Channel Width Calculation by the Third Approach

The Design Element Main River Nile

Damietta Branch

Behery R. & Nubaria C.

Length of the designed ship(Ls) The designed ship beam (Bs ) Channel width in still water (bt) Width increase due to wind (Bs ) Min. permitted radius (R/Ls) Min. radius of curvature ( R ) Width increase for bends (�bu ) Mean current velocity (VW) Increase due to flow current. Increase due to flow current (m)

100.0 15.0 60.0 15.0 6.0

600.0 16.67

VW >0.5 0.5 Bs

7.5

51.0 7.5

30.0 7.5 6.0

306.0 8.5

VW >0.5 0.5 Bs 3.75

51.0 7.5

22.5 7.5 4.0

204.0 12.75

VW >0.5 0.2 Bs

1.5

The Third Design Method - Width of Curved Channel - Width of Straight Channel

99.17 82.5

49.75 41.25

44.25 31.50

4. The Fourth Design Approach This approach [3] is based on the development of two main equations to calculate the waterway width in either of the single or two-way channels as a multiple of the beam of the design ship. The bends radius of curvatures in this method are expressed as the multiples of its length, while the depth of the channel is related to ship draught. Considering each of the type, dimensions and maneuvering condition of the representative design ship, the preliminary design of the navigation channel was estimated. The concept deals with the width and depth of straight navigation sections and gives guideline to determine the compensation in the calculated width due to bends. The navigation channel width elements in a straight reach are shown in Figure 5, which can be evaluated for one-way channel and two-way navigation channel introduced as:

22

Bi

� �

�

=

=

++++=

+++=

n

lipBgBriBMT

Bgr

n

liBMo

WWWWWW

WWWWW

where Wo and WT are the final bottom width of the designed navigation channel for one and two way respectively, WBM is required channel width for maneuvering of the


designed ship to sail safely in very favorable environmental and operational conditions, Wi are additional channel widths due to ship speed and wave, WBr and WBg are the bank clearance sides of the navigation channel as shown in Figure 5., and Wp is the passing distance that comprising the sum of a separation distance based on ship speed and an additional distance based on traffic density.

Figure 5. Elements of Channel Width

In this study the gathered information concerning the design ship, in additional to the relevant modern practices are utilized to design the navigation channel width for the channel width for the main River Nile, Damietta branch, El-Behery Rayah and El-Nubaria canal are presented as shown in Table 8.

Table 8. Channel Width Calculation by the fourth approach


Damietta Branch


- Ship Maneuvering (WBM) - Increase in Width [sum WI ] - Sloping Channel edges (WBr) - Sloping Channel edges (WBg) - Total Increase in Width (WP)

3.0 Bs Bs Bs Bs

1.6 Bs

3.0 Bs Bs Bs Bs

1.6 Bs

3.6 Bs Bs

0.3 Bs 0.3 Bs 1.0 Bs

- Bottom Waterway Width (W) 6.6 Bs 6.6 Bs 6.2 Bs - Ship Beam Width (Bs) 15.0 m 7.5 m 7.5 m - Calculated Waterway Width 99.0 m 49.5 m 46.5 m

COMPARISON OF THE RESULTS In order to evaluate the applied four design approaches for the navigation waterway width, the obtained results are compared. It is worth noting that the increase in width due to bends is defined in the case of the third method than the situation in the other three approaches. While the first two approaches are based on such empirical


guidelines, the other two approaches introduced many other factors that influencing the channel design. Comparison of the obtained results is presented in Table 9 that revealed good agreement for the studied waterways applying the third and fourth design methods. In this case, the maximum resulted variation in waterway navigation width with respect to the first method is limited to 5.1%. On the other hand, as the obtained results by the third and fourth methods showed good agreement with each other, the corresponding results by the first two approaches gave greater width of more than 20%.

Table 9. Comparison of the four methods approaches


Damietta Branch


The First Design Method - Traffic Type - Channel Width The Second Design Method - Traffic Type - Channel Width The Third Design Method - Width of Curved Channel - Width of Straight Channel The Fourth Design Method - Width of Curved Channel

Two-Way 114.0 m Two-Way 120.0 m 99.17 m 82.50 m 99.00 m

Two–Way 57.0 m Two-Way 60.0 m 49.75 m 41.25 m 49.50 m

Two –Way 57.0 m Two-Way 60.0 m 44.25 m 31.50 m 46.50 m

CONCLUSIONS It was concluded that the calculations of the navigable canals dimensions of the first class inland waterways in Egypt from the application of the four mentioned design approaches are close together. The first two approaches were applied to determine waterway width for two-way traffics of straight channels, while the other two methods, are used and applied for straight and curved waterways. It is noticed that the increase in channel width due to bends is defined in the case of the third method than in the other three approaches. The research provides an excellent guidance in the planning, layout, and design of the width of the navigable channel in the Nile River, Damietta branch, Rayah El-Behery and El-Nubaria Canal. REFERENCES �

1. American Association of Port Authorities (1951), Regulatory Review of Sec. 404 of the Clean Water Task Act and the Fish and Wildlife Coordination Act. “Recommendations to Presidential Task Force on Regulatory Relief.


2. Approach Channels, A Guide for Design (June 1997), Final Report of the Joint

“Permanent International Association of Navigation Secretariat (PIANC)” and “International Association of Ports and Harbors (IAPH)”.

3. Boogaard, A. “Hydraulic Studies on the Nile River and its Structures, Phase II”,

Delft Hydraulics of the Netherlands and the Hydraulic and Sediment Research Institute, Fairway Dimensions, Part 3, IWT Course Feb. 1992.

4. Filariski, R. et al. “Design and Improvement of Inland Waterways” The 26th

International Navigation Congress, PIANC, Section I, Brussels, June 1985. 5. Handbook of Coastal and Ocean Engineering (Volume 3), “Harbors, Navigational

Channels, Estuaries, Environmental Effects”. 6. Kray, C.J. (1970), “Supership Effect on Waterway Depth and Alignment,” Journal

of the Waterways, Harbors and Coastal Engineering Division, American Society of Civil Engineers, Vol. 96, May, pp. 497 – 530.

7. Kray, C.J., “Design of Ship Channels and Maneuvering Areas”, Journal of

Waterways, Harbors and Coastal Engineering Division, Vol. 99, No. WW1, pp. 89-110, ASCE, Feb. 1973.

8. McAleer, J.B. Wicker, C.F., Johnsion, J.R., “Design of Channels for Navigation”,

U.S. Army Engineers, 1963. 9. Versuchsanstalt fur Binnenschiffbau e. V. Duisburg, Bericht 590, Naturgross,

experimentelle Untersuchgungen zur Ermittlung der notwendige Fahrwasserbreite in Krummungen stromender Gewasser, 1973.

10. Wicker, C.F. (Ed.) (1965). Evaluation of present State of Knowledge of factors

affecting Tidal Hydraulics and Related Phenomena, Report No. 3. Committee on Tidal Hydraulics, U.S. Army Corps of Engineers, May.

11. Wicker, C.F. (1971), “Economic Channels and Maneuvering Areas for Ships,”

Journal of Water Ways, Harbors and Coastal Engineering, Proc. ASCE, 97(WW3): pp. 443-454.

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