NAIROBI RIVER WOES, THE PICTURE OF KENYANS IN THE WASTE-LADEN WATERS

WHO WILL SAVE NAIROBI RIVER? There is no way to a healthy nation, environment is the way.

Alphonce Magati, Sustainable Urban Environment (SUE) Campaigner and Expert

Snippets

• It is an interesting matter of conjecture when we are caught up in a web of politicking dubbed as reforms, revolution and new dispensation, yet we are ignoring the critical and vital issues in life; deteriorating environment

• A tribute to Kenyatta hospital (or any other hospital for that matter) will ascertain that many patients suffer from water-borne or water pollution related diseases.

• The much hyped Nairobi River Basin Programme, after pooling more than 10 government institutions, have misunderstood the problem and the solution all together

• Apart from the almost tourist-friendly site between the Museum Roundabout and the Globe Cinema Roundabout, the rest of Nairobi River is hysteria.

• The Kazi Kwa Vijana (KKV) on Nairobi River on various sections of the river can be likened to an infantry sent to battlefield without any armoury, for defence or attack

• There is no way to a healthy nation, the environment is the way

SIRI Magatzine. The prevailing effervescent and now reloaded political atmosphere, which is disturbingly endemic to Kenya for a longer time now, condemns some of the critical and vital issues in life to drown in the political cacophony like any other pollutant. It is an interesting matter of conjecture when we are caught up in a web of politicking dubbed as reforms, revolution and new dispensation. At the rate we are taking political appetizers, it is more apocalyptic especially when we are losing the right course. The Hague will come and go, the Ocampo Six will go and come back, but Mother Nature is here to stay with us.

In times of narrow-minded intolerance, in times of political instability and in times of anarchy, it is easier to point fingers and in the process justice accessed; yet when the environment means to avenge on humanity for mistreating her, there will be no scapegoat nor sacred-cow. But where are these sentiments coming from? Take a look. Now more than ever it is an obvious knowledge that 75 % of the ailments that trail Kenyans and African at large, are purely because of poorly managed environment. A tribute to Kenyatta hospital (or any other hospital for that matter) will ascertain that many patients suffer from water-borne or water pollution related diseases. But the question that begs for an immediate answer is, why is that continuing unabated?

It is amazing that in a country with a natality explosion of over a million people annually cannot predicts its future waste generation in black and white. A close eye on the Nairobi River itself could speak volumes of how we are on a non-moving lane, environmentally speaking. Despite the much hyped Nairobi River Basin Programme, the pace and vaguely defined institutional responsibilities clearly state how we have misunderstood the problem and the solution all together. First, pooling more than ten institutions into one objective with a cheque of more than 3.5 million dollars yet deliver such undoing, is a self-inflicted insult and gets gravely close to corruption and impunity.

Nairobi River Rehabilitation Program (NRRP)

For starters, Nairobi River Rehabilitation Programme is a multi-stakeholder undertaking tracing back into 1999 that merge the Government Ministries, United Nation Environmental Programme (UNEP), UN-Habitat, the private sector and the civil society to restore and manage the river’s ecosystem. But apart from the tourist-friendly site between the Museum Roundabout and the Globe Cinema Roundabout, the rest of Nairobi River is hysteria. Nairobi River and its tributaries traverse through the whole of Nairobi; from Mathare River, Motoine and Ngong’ Rivers join and flow to Athi River and eventually the Indian Ocean.

Starting at the bridge of James Gichuru Road, the river is fairly clear with a faint trace of smell. At the next stretch to the Museum Road and to the Globe Cinema roundabout, the river is still clear. From this section the total overkill of the river livelihood begin. The automotive garages, car washes, illegal sewage discharge, solid waste dumping take over the river. At the Kariokor Roundabout, the stench heightens. Down further, it meanders into Bondeni and Gikomba market. Here the worst damage is not enough as it meets more shoddy garages. As the river flows through Eastleigh, Buruburu, Kariobangi, Dandora through Kasarani it is no longer a river but an open sewer line. Mathare River, a tributary, starts to get the same lashing at Mathare phase four. Ngong River, another tributary, gets the worst damage from the industries illegal and untreated discharges laden with all chemicals and heavy metals. All these enter Athi River and threaten lives downstream. A case in point is the Kabaa irrigation scheme which is straining from solid waste and chemicals resulting from Nairobi River.

The short stretch between Museum Bridge and Globe Roundabout has not won the hearts and minds of Kenyans, and donors too, given the funding and time period. Something needs to be done.

Kazi Kwa Vijana (KKV) on the River

The Kazi Kwa Vijana (KKV) on Nairobi River on various points can be likened to an infantry sent to battlefield without any armoury, for defence or attack. They work against hostility from people farming along the river banks especially in Imara Daima estate and Mukuru kwa Njenga. Illegal sewer lines and discharges by known and unknown industries/firms at night when there is no surveillance. The presence of illegal electricity wiring across the river poses more danger than the polluted river itself. A part of Donholm estate uses the river as a dump site. Despite of all these, the KKV people have no protection gear leave alone appropriate river-cleaning tools.

There is no way to a healthy nation, environment is the way. Contrary to popular expectation, just encouraging a 10 % tree cover in Kenya is not good enough for environmental sustainability. And especially when Nairobi, Kenya is the home of the United Nations Environmental Programme (UNEP), as well as many other international and national organisations like National Environmental Management Authority (NEMA). A visitor to Nairobi could be easily mistaken that this city is the cleanest city. Behind the glittering facade, Nairobi is brimming with filth jeopardizing a normal life. A visit to many of our bedroom-suburbs or estates confirms this. There is dirt and dirty water almost everywhere! As for garbage, the eyesore is everywhere including on roads, open spaces and rooftops. Indeed, many urban dwellers wish for sustainable environment. But all the responsibilities will start with us as individuals. Otherwise, environmental negligence and degradation, which is the greatest hazard to existence both on earth and in the heavens above, will cost us dearly.

Name: Alphonce M. Magati

Environmental Engineering,

JATROPHA PLANT & UoN THINKING

JATROPHA PLANT, THE TRUTH BEHIND

This is attracting the world’s eye toward the nearest renewable energy sources to quench the rising energy consumption which is posing new challenges to both local and national governments worldwide. We cannot overemphasise the urgency, but of more significance is the issue of environmental-friendliness. The latter being given more weight, the focus towards bio-fuels is particularly intensified

Snippets

1. Bio-energy is the only promising avenue unless we want to continue committing the grave error—philistine pollution.
2. Attaining energy security means we can not only unchain ourselves from dependence on fossil fuels but also realise environmental security and a whole assemblage of other principal development and poverty alleviation goals.
3. It is indeed in line with green technology tune of obtaining fuels that endeavours to eliminate dangerous climate changes and above all strive to reduce dependency on imported oil.
4. Jatropha is drought resistant and less attacked by pests; therefore it can be intercropped easily
5. ‘B” factor, the amount of biodiesel in any fuel mix guides the significance.

Energy is the centre-point of any developing or developed country. Speak of energy, and suddenly auto-mobile and other oil-consuming machineries roll into big picture. The availability of oil, the substantial fossil fuel of the past millennium, is peaking, and consequently its production declining in an alarming rate. This is attracting the world’s eye toward the nearest renewable energy sources to quench the rising energy consumption which is posing new challenges to both local and national governments worldwide. We cannot overemphasise the urgency, but of more significance is the issue of environmental-friendliness. The latter being given more weight, the focus towards bio-fuels is particularly intensified

The future argues that bio-energy is the only promising avenue unless we want to continue committing the grave error—philistine pollution. The advent of world Biosystems heralded the much awaited bio-energy, bio-fuel, bio-diesel just but naming a few. And now a new day has finally come for the likes of soy-beans, rape seeds, mustard, flux, croton and jatropha plants to have their say towards energy security. Remember, if we attain energy security, ladies and gentlemen, we cannot only unchain ourselves from dependence on fossil fuels but also realise environmental security and a whole assemblage of other principal development and poverty alleviation goals.

What is Biofuel?

Bio-fuel, according to Biamah Elijah, Professor in the department of Environmental & Biosystems Engineering, is a solid, liquid or gas fuel that is fashioned organically from biomass by a process called trans-esterification. It is indeed in line with green technology tune of obtaining fuels that endeavours to eliminate dangerous climate changes, attempts to salvage the current economic slow-down, and above all strive to reduce dependency on imported oil. Since bio-fuel production can be implemented anywhere and does not require any special rig, its easy execution processing caters for the following demands and opportunities:-

<!--[if !supportLists]-->1. <!--[endif]-->An option to the depleting oil reserves

<!--[if !supportLists]-->2. <!--[endif]-->Reduction of our foreign exchange by cutting on import costs of oil

<!--[if !supportLists]-->3. <!--[endif]-->Deter climate change and global warming due to carbon dioxide and other dangerous pollutants due to fossil fuels.

<!--[if !supportLists]-->4. <!--[endif]-->Discover and nurture highly-yielding crops that generate highest bio-energy density

Jatropha in the Spotlight

Following a cyclic see-saw by engineers and scientists over the outstanding bio-plant(s), the jatropha tribe took the standing ovation.

This is a special and simple plant which, due to its enormous interest, balances the equation of biodiesel production all in all.

Jatropha is being hailed by all and sundry as a potentially ideal candidate for future Biofuels; and as the only option for Kenya. Let’s imagine like this, suppose we preserve Mau complex for jatropha planting all in a bid to protect and conserve the dear environment, don’t you think this would be a stitch in time: increased vegetation, increased energy! The key is in growing the jatropha to be used as a bio fuel. Once dried out and crushed, the seeds yield oil which can be burnt in almost any diesel engine—with little or no modification. Just as simple as that. More importantly, the plant attraction lies in the fact that it can grow anywhere, even in the poorest soil like in Ukambani-land, needs a very little water to survive and will yield seeds for more than half a century. Good people, what are we waiting for?

The Poison Plant, the Antidote to Desecrated Planet

With the help of Biamah, the Environmental Engineers together with their counterparts from mechanical Engineering, have something in common, something special for Kenya: cheaper and more environmentally friendly alternative to fossil fuel.

As a good kick-off, the department of Environmental Engineering has secured a land with the help of professor, and by the end of this November a thousand of jatropha tress shall be planted.

In India itself, as we speak, has already planted over 11 million hectares. Other countries like Gran Chaco of Paraguay, Mali, Brazil and Singapore are already enjoying the sweet fruits of their sweat clean energy.

Jatropha is just one of a number of possible biofuel plants. However, the elegance is that jatropha is drought resistant and less attacked by pests; therefore it can be intercropped easily with other cash crops such as coffee, sugar, fruits and vegetables without much misery. It doesn’t require a lot of fertiliser yet the yield is higher: Ranging from 1,600—2, 000 kg/ha, which correspond to extractable oil yields of 550—680 litres per hectare.

Its characteristic toxicity is advantageous too. With its deadly inedible seeds and the irritating milky sap from the bark, jatropha is put at a pedestal where no competition of other demands. What’s more, like any other plant, jatropha absorbs carbon dioxide while they are growing, effectively cancelling out the carbon dioxide emitted in the biosphere and cryosphere.

Environmental Arguments

Bio-diesel, ideally made by chemically reacting lipid (jatropha oil) with an alcohol, does not emit carbon or other gaseous emissions that are responsible for global warming. When burnt, the paraffin/diesels release carcinogenic toxins such as benzene, toluene, formal dehyde, acetaldehyde, acrotein and soot into the air; as for bio fuel it’s environmentally safer for ozone protection and use in industrial development. Biodiesel has virtually no sulphur or lead content. And, we shall be good to go the extra mile to allow developing countries like us to be self-reliant rather than depend on Middle East for imports.

By use of a system known as ‘B” factor, the amount of biodiesel in any fuel mix can be stated easily. For instance B20 is fuel containing 20% biodiesel and 80% petroleum diesel, while B100 is pure biodiesel. B20 can be used in unmodified diesel engines, but B100 require specific engine modifications to avoid maintenance and performance problems. Biodiesel has different solvent properties than petro diesel, and will degrade gaskets, require change of fuel filters on engines, use of FKM after switching to biodiesel blend.

ALPHONCE M. MAGATI

PLASTIC ROADS; WASTE MANAGED!

PLASTIC ROADS

Snippets

1. Kenya has taken a serious stab in the past at dealing with urban solid wastes (plastic majorly), though laced with mixed results.
2. Lifespan of a road can be distended three-fold from the normal four or five years to almost one and half decades without need of repair
3. It might sound like recycling but no, it’s plastic waste’s “cemetery” instead of lying idle in landfills
4. Each kilometre of road with an average width of about 3.78 metres require over two tonnes of plastic to blend; it will help to eliminate this non-decomposable monster!

Finally the eyesore thin polythene bags, carry bags, disposable cups, pet bottles, etc that have been a social and environmental nuisance, can be dismissed by a wag of the index finger. It is a sight of relief now that the knowledge of using plastic wastes to make roads is a much awaited technological messiah. This connotes a matter-of-fact end to pollution caused by this non-biodegradable waste that is reposed in this new technology. Plastic use is very popular and the prevailing quest for better long lasting roads is also a reality. For your information, Kenya has taken a serious stab in the past at dealing with urban solid wastes, though laced with mixed results. In 2005, the Kenya National Cleaner Production Centre (KNCPC) came up with a plastic waste management strategy for the city of Nairobi underlining the need to utilise dumped plastic in a study commissioned by UNEP (United Nations Environmental Programme). The strategy was partially successful. The dossier pointed the adverse effects and economic challenges that plastic bags thinner 15 microns in thickness posed to the environment.

Two years down the line, the manufacturer of such bags was banned, and a 123 p.c. tax on thicker ones imposed. The solution was to not make plastic in the first place, rather than making it without knowing what to do with the waste. Unfortunately, the ban was summarily suspended in the wake of intense lobbying by the manufacturers. And expectedly, uncollected waste caused by the plastic is what we evidenced everywhere and anywhere. Arguably, the cost of road construction may be slightly higher compared to the conventional method but this should not hamper the adoption of the technology as the benefits are much higher than the cost. It might sound like recycling but no, it’s plastic waste’s “cemetery” instead of lying idle in landfills!

First, durability is vouched for authenticity and then employment created in the process. The latter, probably through setting up plants for collection of the waste plastics and then mixing them with bitumen, or creation of self-help groups that collect and shred the waste. Public too can get the opportunity to sell their domestic plastic wastes instead of discarding them into the dustbin.

A team of engineers from RV College of Engineering, Bangalore, invented this technique of using plastic waste for road construction under the strength-and –durability cogency, while addressing the problem of disposal of plastic waste in an environment friendly manner. Methodically, the plastic is simply shredded using a plastic crusher, melted and mixed with bitumen in a specific ratio. By mixing, the road withstand high temperature fluctuations since the plastics act as strong binding agent making it last longer than those asphalted with ordinary mixture. Long durability is crowned overall because rainwater will not seep through, because of the imbedded plastic hence no effect underneath—ground unequal expansion and contraction.

The lifespan of a road can be distended three-fold from the normal four or five years to almost one and half decades without need of repair is in itself a resounding yes-yes. In fact, environmentally speaking, the world can finally smile; as each kilometre of road with an average width of about 3.78 metres require over two tonnes of plastic to blend, it will help to eliminate this non-decomposable monster!

Public plastic roads are touted to be the future tender bidder, deal-maker. Who knows, the Ministry of Roads is ...searching...

ALPHONCE M. MAGATI

ENGINEERING BEHIND THIKA ROAD CONSTRUCTION

 

"the research of which this disquisition forms a record, however, broke new grounds which it aimed deliberately at unravelling and illustrating the steps and the reckoned eventuality. Rarely do you meet this kind of exposition, so read on...

In a city where most traffic rules are either non-existent or are flouted left, write and centre, the roads become a perfect battle field. Swapping between lanes, hooting for vehicles in front to move away yet the jam is 20 metres long ahead...

 

The Design AND Engineering

Sneak peek

• Cash on each segment
• Extreme construction
• Muthaiga Roundabout
• Highway or Boulevard
• Regimental Highways (Autobahns)
• Muthaiga--KU
• The Engineering beneath the Surface
• KU—Thika
• Priority control and Restraints
• Plastics for Road Construction(future)

It’s argued and even confirmed that if you can survive in Nairobi roads as a driver, you definitely deserve NFS licence primarily because all other odds have been eliminated. In a city where most traffic rules are either non-existent or are flouted left, write and centre, the roads become a perfect battle field. Swapping between lanes, hooting for vehicles in front to move away yet the jam is 20 metres long ahead, drivers who join the main road haphazardly without checking for the oncoming traffic, or squeezing in front to force their ways, these are just few examples of common madness in our daily roads.

The long snarl-ups caused by ministerial motorcade are not spared too. Matatus too, love them or otherwise, they are here to stay. Their lunacy, mindless driving will continue existing all in scramble for “space.” But all these will become a thing of the past given that the ministry of Roads has fully embarked on changing the faces of our roads into super-highways and flyovers to decongest the city of Nairobi.

EXTREME CONSTRUCTION

I am not yet acquainted with the engineers on the site and the strategies laid in store for the effectual action, but the research of which this disquisition forms a record, however, broke new grounds which it aimed deliberately at unravelling and illustrating the steps and the reckoned eventuality. Rarely do you meet this kind of exposition, so read on.

Roads and motor vehicles are correlative, and one without the other will simply be sending bright minds back to the dark ages to search for the other lost “sheep.” Good vehicles need good roads, and vice versa. It’s been argued that one important quality of a road is accessibility. This, technically, describes how vehicles are allowed to enter and exit a rad. By controlling access to a road, the road can support, in a given time, move traffic at higher speeds i.e. reduced traffic snarl-ups.

The Ksh. 26 billion project involves construction of two major types of roads:

(1) highways, and (2) boulevard or urban streets. Each of the two types control access to different levels, differ in location, the amount of traffic it can safely support, and the speed at which traffic can safely travel. These parameters shall be fully employed in the three demarcated segments, namely:

• Muthaiga Roundabout— Uhuru Highway Section

• Muthaiga Roundabout –KU Section
• KU – Thika Section

[A] Muthaiga Roundabout –

For this section, the contract bid was deservedly procured by China Wu Yi Company with a cheque of Ksh. 8, 030, 386, 596 dangling in their able hands. The contract narrative clearly laid the action and it involved construction of four-lane flyover across Globe Roundabout then widening the linking to 8-lanes from the current 6-lanes which shall meet a flyover on Muthaiga Roundabout. Wu Yi shall then set up an underpass at Pangani. Eventually, footpaths shall crown all the roads as a sign of pedestrian precincts.

Together, –

Museum Road

– Museum Hill Roundabout will be worked on, turning

Forest Road

into 6-lanes from the current 4-lanes, with a median (divider in the middle of the road). Similarly Museum Hill Roads will become 6-lanes as they erect a forked flyover on

Limuru Road

.

The construction of this section shall be much biased to erection of urban street rather than superhighway. To understand which one, it’s prudent of us to distinguish between the two primarily.

HIGHWAY OR BOULVARD DESIGN

As boulevards endeavour to cover cities, towns and suburbs, highways on the other hand strive to connect to or more major cities. Despite the fact that both are constructed using similar principles, boulevards are contrived to accommodate underground public facilities, such as electrical wiring, water and sewage pipes, and telecommunication lines. Besides, they are built around existing buildings and other barriers like rivers. The boulevards, which often control vehicle movements by use of traffic light and signs, can be classified into two on the basis of the amount of traffic designed to carry: collector streets and arterial streets. Collector streets convey traffic from residential streets to the main roads called the arterials. In cities like Nairobi, the arterials are often similar to highway in construction even though they are located within city limits. For the highways, the contrast lies in the amount of access control they have (i.e. the amount of traffic they are designed to carry). We have:

REGIMENTAL Highways aka Motorway/ Autobahns

The autobahns can handle the most traffic with the lustre of having three, four or more lanes for each direction of travel and often include medians to separate traffic moving in opposite directions of travel and often include medians to separate traffic moving in opposite directions. Vehicles that enter or exit the autobahns can do so only at incontestable points usually by using a special entrance and exit ramps (slope that join two parts of a road when one is laid higher than the other). The ramps grant vehicles access to the road without disturbing the flow of traffic. Incoming vehicles must merge with the flowing traffic, and vehicles leaving the highway use exit ramps that guide them off the highway without blocking the traffic behind. The burden of intersection with other roads is eliminated by use of special bridges called overpasses or tunnel-like structures called underpasses.

NON-REGIMENTAL Pass ways handle less traffic comparatively, and they intersect other roads at-grade (at the same level), rather than using overpasses or underpasses. This kind usually encourages traffic jam as vehicles scrample to find through way.

Now we know...

[B] Muthaiga Roundabout—KU

With the above design technique in mind, this segment must be designed as a high-speed autobahn with very limited access and exit. Sinohydro Corporation, the concerned contractor, pledges to widen the carriageway from Muthaiga—Kasarani into 8-lanes, and from Kasarani – KU into 6-lanes with a cheque of Ksh. 8, 690, 568, 489 the budget entails construction of three underpasses, at Kahawa, KU and at the former Nakumatt Building; three flyovers, at Kasarani Roundabout, Githurai Roundabout and Interchange at GSU Roundabout.

To support vehicles (light and heavy) moving at high speeds and to ensure durability, the road is made up according to standing civil conventions. Lets see what Sinohydro Corporation is devising...

The Engineering beneath the Surface

Basically a road has at least three distinct layers but the number often depends on the intended use of the road, number of vehicles and the budget constraints. From the bottom upwards, the layers are:

• the Topmost (pavement)
• the Base Course
• the Roadbed

The Roadbed is the base of a road. Natural soil is the most common roadbed material, but in case of wet-land, stones do better. Roadbed is shaped (consolidated) to make a smooth, level surface that will support the layers built over it. Engineers use bulldozers, compressors and other equipments to distribute soil evenly and firmly along the roadbed. The soil can be stabilized by adding or mixing materials such as calcium chloride, lime or Portland cement to the soil.

The Base Course is often made up of compacted gravel and it rests on top of the roadbed. Mostly, without adequate drainage, roads may buckle as water distends the ground underneath. To disengage this inconvenience, drainpipes are usually installed within the base course to control rain and moisture drainage. For very busy autobahns or motorways, a second layer is included to the base course for extra support.

The Topmost is made of wearing solid layer of pavement and is designed to be smooth and to withstand corrosion from traffic or weather. The pavements are of two main types:

• Bituminous (or flexible) pavement
• Concrete (or rigid) pavement

Bituminous Pavements is cheaper and easier to construct, but it requires more maintenance. The bituminous material, which maybe a by-product of petroleum like asphalt (or mixture with plastic waste), softens when heated and can be prepared and applied in a wide range of concentration. Asphalt, a thick bituminous material can be used directly as a pavement, or commonly mixed with aggregate for added strength and traction. Then thin overlays less than 2cm deep or in layers several centimetres deep is applied accordingly.

[The asphalt and aggregate are usually mixed and heated at their base station. The material is then transported to the construction site, where it is spread directly over the base course and compacted using a roller-dozer.]

Concrete Pavement, on the other hand, lasts for a very long time with minimal upkeep but is much more expensive. The concrete, which has been used once in , is generally laid as a single thick layer directly over the base course. With a thickness of about 30—35 cm, the concrete is usually laid in long sections or slabs of varying length. The metal bars or dowels are inserted between the slabs to help connect the joints, holding the slab firmly. Concrete despite it renowned for being strong material with a high compression tolerance, it has poor tensile strength. So when the ground underneath expands and contract unequally due to seasonal or weather changes, the concrete become prone to cracking. Cracks can occur at or near the joints where concrete slabs meet or on the slabs themselves. Deep cracks can allow the broken concrete slab to move upward or downward creating an uneven road surface. To eliminate this, reinforced concrete is preferred. This one contain steel bars or mesh imbedded within the concrete layer which help hold the concrete together over time, even if cracks occur. But cost is the deciding factor.

[C] KU—Thika

To be continued in Part 2...  

Mbagathi Way

Forest Road

University Way

Uhuru Highway

THE ENGINEERING BEHIND THIKA ROAD CONSTRUCTION