Bypasses, Expressways and interchanges: The changing face of Nairobi

This story has significance for readers across Kenya and beyond.

If there is a suburb that wears the story of explosion of Nairobi’s modern roads on its sleeves, it has to be Kamakis, the satellite town right in the middle of Nairobi and Thika.

Tucked at the intersection of Thika Superhighway with Eastern and Northern bypasses in Ruiru, Kamakis has built a name as the real estate haven of Kiambu County, attracting thousands of Kenyans who have moved in pursuit of space outside the city.

The ideal Kamakis today is a beehive of activities with bodabodas, trucks loaded with sand and bricks, hardwares, supermarkets, real estate companies, Nyama Choma joints blending all in.

Propelled by accessibility that came construction of the three crucial roads, Kamakis is today one of the fastest growing suburbs, and the rural folk who have lived here for decades coexist with middle-class families that are moving in.

Land prices have skyrocketed too. A parcel of land that cost Sh18,000 around 1986 now goes for Sh60 million. The latest land price report by real Estate firm, Hass Consult, shows that by June 2026, Ruiru- where Kamakis is located- had the highest growth in land prices over the past 10 years, to Sh42.2 million for an acre.

Kamakis is one product of Nairobi’s modern transport system that has come with an investment of over Sh200 billion in bypasses, expressways and superhighways in the past two decades, leaving 183km of roads behind.

Thika Superhighway

It started with the Thika Superhighway project that expanded an initial four-lane road into an eight to 12-lane superhighway, opening up one of Nairobi’s most congested roads.

Today, the 50km road completed 14 years ago has played a major role in opening up commercial and residential areas in Nairobi and Kiambu counties.

Featuring nine interchanges, 12 flyovers and overpasses, and about 18 footbridges across several estates, the road sparked a business boom triggering the opening of at least six major shopping malls, colleges and other businesses, and many people working in Nairobi now live in areas along this road.

The road cut travel time between Nairobi and Thika from highs of two to three hours, to about 30-45 minutes during low traffic.

An appraisal report by the African Development Bank (AfDB) in 2007 prior to its construction had acknowledged that about 60,000 out of all the 840,000 vehicles operating in Kenya at the time, used Thika road daily, projecting that public transport demand in the country would grow from 1.8 million trips at the time to 2.9 million trips by 2025.

Eastern Bypass

It’s at Ruiru where Thika Superhighway meets the Eastern Bypass, the first of the Nairobi’s bypasses to be constructed, and it’s also where Kamakis sits.

A trip along the 27km Eastern Bypass takes around 30 minutes, starting from Baraka Roundabout where the Airport North Road, which branches off Mombasa Road at Cabanas, ends. The Eastern bypass ends in Ruiru where it meets Thika Superhighway.

Along the route, it’s difficult to miss the impact this four-lane dual carriage way has had on estates such as Utawala and Kamakis where it ends, as the road links Mombasa Road to Thika Superhighway.

It changed Utawala from a dusty and sparse estate, into a thriving commercial and residential hub, where supermarkets, including national brands such as Naivas and Quickmart, banks and real estate companies have pitched camp here.

The Eastern Bypass was initially built as a single carriageway between 2009 and 2014, but heavy traffic informed its expansion into a four-lane dual carriageway that was completed in 2022, in total costing Sh21.8 billion.

In Ruiru, where the road intersects with Northern Bypass and Thika Superhighway, the population of people living there grew by 54 per cent to 371,111 over the decade to 2019.

Northern Bypass

The road starts at Ruiru flowing through Membley, Kahawa West, Marurui and Githurai 44, then intersects with Kiambu Road at the Four Ways junction flowing through Githogoro to Two Rivers Mall, Ruaka.

It is the only bypass still built as a single carriageway and the government plans to expand it into a dual road to ease frequent traffic congestion during peak hours, particularly around Kahawa West and Githogoro.

“The project will convert the current single carriageway into a dual carriageway and include the construction of eight interchanges, overpasses, and underpasses, as well as the development of non motorised transport facilities, including walkways and cycle paths, improved drainage systems, and enhancements to adjacent roads,” the Ministry of Roads said in July last year.

A trip along the Northern Bypass reveals the same story of how Kenyans have curved a niche out of the roadside economy, venturing into everything from roadside plant nurseries, cabro blocks, petrol stations, clubs and timber yards, to opening schools, churches and hotels.

The 20.2km road built at a cost of Sh9.3 billion features basic road designs though key businesses and institutions such as the Kenyatta University Teaching Referral and Research Hospital (KUTRRH), Two Rivers Mall and Glee Hotel.

Western Bypass

The four-lane, dual carriageway starts at Ruaka, few kilometres from where the Northern Bypass terminates and flows for 16.8km through Wangige shopping center, a number of sleepy villages that it sprung to life, to Gitaru where it connects with the Southern Bypass.

Constructed between 2019 and 2023, the 16.8km road was meant to divert traffic from entering the Nairobi Central Business District (CBD) for motorists connecting between the Southern Bypass, Nakuru-Nairobi road and areas such as Ruaka who didn’t need to enter the city.

The road cost taxpayers Sh20.9 billion and features some four interchanges, about 15 bridges and pedestrian underpasses and service roads that have since opened up several residential and commercial areas.

Southern Bypass

Gitaru Interchange, which is at completion stages and partly in use, is the main intersection between Western and the Southern Bypass, allowing vehicles moving between Ruaka - Kikuyu directions to pass under the Nairobi - Nakuru Highway.

Constructed between 2011 and 2016, the Southern Bypass’ major role has been to divert trailers moving between Mombasa and the Uganda border, and and other motorists on an express journey not to pass through the Nairobi City Centre.

Instead trucks and other motorists travelling express use the four-lane dual carriageway to take a 29km round trip from the Gitaru Interchange, passing through Kikuyu, Dagoretti, Karen and Kibera, to merge on the Mombasa Road at the major Ole Sereni interchange.

Other than diverting trailers and express motorists, the road has inspired an organic culture among Nairobians, who now throng some of the spacious roadside sections of the road and interchanges for park and chill moments, including the Thogoto Interchange and Ngong Road forest sections.

The Ole Sereni Interchange serves as a multi-level, grade-separated road junction connecting the bypass to Mombasa Road, as the Nairobi Expressway towers above.

The Sh21.7 billion project has been one of the major roads ridding Nairobi of traffic snarl ups and has also served to take up traffic for persons operating between Kikuyu-Karen-Mombasa Road directions, without a need to pass through the CBD.

Outering Road

While not a bypass per se, the 13km Outering road has been one of Nairobi’s major road projects that addressed severe traffic gridlocks when it was expanded from a narrow, dusty and pothole-ridden single-lane route infamous for chaotic roundabouts, into a modern dual carriageway that now features service roads, interchanges, and footbridges.

Constructed between 2014 and 2021, the road has improved traffic conditions between busy Eastland Estates from Pipeline, Tassia, Donholm, Kariobangi, ending at Allsops where it intersects with the Thika Superhighway.

“The road was designed to serve an area with a population of at least 3.08 million people, who are mostly in the middle-to-low income groups, whose livelihoods are mostly derived from informal roadside businesses,” the AfDB said in March 2021, when the project was completed.

AfDB, which funded the construction of Outering, reckoned that before expansion of the two-way single carriageway, over 1,000 vehicles used a single lane of the road every hour, 30 per cent beyond its capacity.

Expansion of the road increased travel speed from an average of 4.5km/h to 58km/h at peak hours between 2012 and 2020, the lender said.

More roads coming...

Still, the government is not done launching more roads around Nairobi, with current plans showing that roads valued over Sh100 billion are on the way.

There are plans to expand the Northern Bypass into a four-lane dual carriageway after cabinet approved the decision in July last year, the dualling of Kiambu Road at an estimated cost of Sh30 billion is coming, and there are talks of construction of Nairobi- Thika Expressway at an estimated Sh85 billion.

The Kenya Urban Roads Authority (Kura) says it has spent over Sh200 billion on development of urban roads since it was established, and has more plans to modernise Kenya’s urban transport.

“Over the period, KURA has implemented numerous road projects across the country, including construction, upgrading, and rehabilitation of urban roads. These projects include dual carriageways, Non-motorized transport system (NMT) facilities, bridges, drainage systems and junction improvements,” the agency says.

It says it constructed 2,202km new roads between July 2013 and June last year, easing traffic congestion, improving access to businesses and public services and supporting regional economic development.

In particular, Kura says the bypasses, expressways, modern junctions and expansion of roads have cut traffic jam challenges, and now plans to introduce Bus Rapid Transit (BRT) to support mass movement and discourage individual modes of transport.

The agency also plans more technology rollout to manage traffic and reduce reliance on police officers on the roads, including automated traffic management systems, sensors, cameras, and real-time monitoring.

Already, the government has introduced speeding cameras along several Nairobi roads, including the bypasses, which have been used to monitor and penalise speeding motorists.

Kura says it is “prioritising interchanges, elevated roads, and diverting traffic to alternative towns/routes to relieve congestion in high-demand urban centers.”

Reporting originally appeared via Nation Africa. Read the full source for additional context.