Wednesday, February 15, 2012

Ten Avon River Bridges, Spans & Quakes

Wed 15.02.12. I'd already closely looked at 4 Avon River bridges in Christchurch CBD, former red zone. I was curious to see what damage 17 months of quakes had done to 10 remaining downriver bridges, where Avon River flowed through serial quake trashed eastern suburbs, from Stanmore Rd Bridge on the CBD fringe to South Brighton Bridge on Avon River Estuary.

Besides violent shaking danger throughout Christchurch & quake rock fall danger in the Port Hills, along Avon River & Heathcote River, liquefaction danger added to shaking hazards prevalent in riverside & swamp suburbs.

Given the volume of ground water forced above ground & liquefaction mud produced by several quakes, generally quakes were slumping riverbanks or raising riverbeds & raising / lowering estuary beds & returning swamp suburbs back to swampland. Nasty for anyone owning property on "reclaimed" wetlands, riversides, or coastal dunes.

The day I looked at the bridges, Avon River was swollen from heavy rainfall over the last couple of days. It was the same rainfall pattern pre 22.02.11 quake, which caused so much liquefaction damage.

On my drive downriver with numerous pic stops, I bumped along quake trashed, patched roads - River Rd, Dallington Tce, Locksley Ave, New Brighton Rd, Owles Tce, Union St, Estuary Rd. There'd been little improvement in eastern suburb roads I drove since the 22.02.11 quake, a year ago. Council still had much work to do on infrastructure repair & rebuild. (Years later, 2016, roads were still crap).

Like the 4 CBD bridges I'd seen, 8 concrete road bridges further downriver had strong spans, relatively unscathed by serial quakes. (Except for 2 trashed footbridges, 1 concrete, 1 steel). A couple of concrete road bridges were 2 span, the rest further down river were 3 span, as Avon River widened towards Avon Estuary.

Quake damages were at concrete joins between bridge abutments & spans, where span / abutment movement happened during quakes. Some spans had banged against abutments, some moved sideways, some rotated, some spalled concrete chunks at joins. Some concrete abutments either sunk into river mud & / or splayed at odd angles away from bridge spans

Damage giveaways were acute angle gaps between span ends & abutments, with abutments skewed from the vertical, split steel hand rails at odd angles, skewed from the vertical, especially at abutment joins, quake tilted light poles & plinths on bridges, mangled or displaced rubber linings at bridge / road joins, or below spans, spalled concrete curbs & concrete paving, cracked or buckled tar seal.

Stanmore Rd Bridge: Concrete, 2 span. Spans OK. Stone light plinths, quake cracked, 1 fallen, Avonside Dr side. Quake tilted abutment, River Rd side.

Images, quake damaged Stanmore Rd Bridge:


15.02.12. Quake trashed, abandoned house, River Rd, nr Stanmore Rd Bridge


15.02.12. Stanmore Rd Bridge, quake damaged light plinth, cnr Stanmore Rd / River Rd





A bronze plaque on Stanmore Road Bridge read:

STANMORE ROAD BRIDGE

In pre-European times the Avon, then known as Otakaroro, was at this point the boundary between two families within the Ngai Tahu tribe. The swampland adjacent to the bridge site provided highly prized foods for the local Maori.

In the early days of European settlement the Avon and Heathcote rivers were used as vital shipping access to the infant City of Christchurch. Bridges were regarded as a nuisance and their construction was discouraged outside of the city boundaries.

The first Stanmore Road Bridge was built on this site in 1862 and largely ignored ships statutory navigation rights. As a result in 1865 part of the bridge was cut away by Mr John Mills and his men to allow his steamer 'Maid of the Avon' to pass. 

By 1875 the bridge was in a state of bad repair and in 1878 a new bridge was constructed with a 6ft path each side of a 24ft carriageway. Since then the bridge has been further widened and strengthened over the years.

By 1995 the old bridge had reached the end of its economic life and was replaced by the present bridge. The stone facing on the wing walls and the light support columns are built from materials recycled from the old bridge.

Many Avon River bridges had abutments sunk or tilted so far into river mud that bridge spans were above the abutment level. That caused a ski-jump effect where vehicles had to slow down before the bridge or on the bridge to carefully negotiate the drop / rise either side of the bridge. If one raced across a damaged bridge the vehicle's sump & exhaust would be gutted. Never mind all the quake pot holes, sink holes, cracks, lumps & bumps on all the roads.

15.02.12. Stanmore Rd Bridge, quake tilted abutment, cnr Stanmore Rd / River Rd. See ski-jump effect on car crossing the span / abutment displacement



15.02.12. Stanmore Rd Bridge, quake damaged abutment & collapsed light plinth, cnr Stanmore Rd / Avonside Dr.

Despite road patches along Avonside Dr towards Linwood Rd, slumping / cracking by Avon River was still happening a year post Feb 22 quake. More road patching was required. Post quakes, wherever one drove in Christchurch there were detours, as road works progressed / regressed slowly. Corner Avonside Dr / Linwood Rd / Woodham Rd was still a mess with a detour away from Linwood Rd, as water pipes still needed attention a year post Feb 22 quake.


15.02.12. Avonside Dr view of quake damaged Stanmore Rd Bridge

Swanns Rd Bridge: Concrete, 2 span. Spans OK. One concrete abutment River Rd side, big crack with reinforcement steel exposed & rusting. Opposite abutment, spalled against spalled span end, Avonside Dr side. Swanns Rd Bridge didn't look safe.

Images, quake damaged Swanns Rd Bridge:


15.02.12. Quake slumped footpath, Avon River bank, Swanns Rd Bridge, cnr Swanns Rd / River Rd



15.02.12. Swanns Rd Bridge, quake cracked abutment, cnr Swanns Rd / River Rd,


15.02.12. Swanns Rd Bridge, quake cracked / slumped pavement & abutment, cnr Swanns Rd / River Rd


15.02.12. Swanns Rd Bridge view of quake trashed, abandoned housing, Avonside Dr. See post quake, blue water pipe on post quake, patched pavement


15.02.12. Swanns Rd Bridge, quake damaged join between abutment & span, cnr Swanns Rd / Avonside Dr


15.02.12. Swanns Rd Bridge, quake displacement of abutment & bridge span, road deck, cnr Swanns Rd / Avonside Dr


15.02.12. Swanns Rd Bridge, spalling between span & abutment, cnr Swanns Rd / Avonside Dr


15.02.12. Avonside Dr downriver view of quake damaged Swanns Rd Bridge


15.02.12. Avonside Dr view of spalling between span & abutment, Swanns Rd Bridge, cnr Swanns Rd / River Rd


15.02.12. Avonside Dr view of quake cracked / slumped pavement & abutment, Swanns Rd Bridge, cnr Swanns Rd / Avonside Dr



15.02.12. Quake damaged house, River Rd, nr Swanns Rd Bridge


15.02.12. Quake damaged pavement, River Rd, nr Swanns Rd Bridge

A sign on a River Rd, red zone, house fence read:

       DANGER
UNAUTHORISED
      PERSONS
      KEEP OUT

Medway St Footbridge: Steel, 1 span. Quake trashed, steel span & supports twisted & buckled. Fence cordon closed, since the 04.09.10 quake. Medway St Footbridge was deconstructed for storage at Ferrymead Heritage Park

Images, quake damaged Medway St Footbridge:


15.02.12. 04.09.12 quake trashed Medway St Footbridge, between River Rd & Avonside Dr. Medway St Footbridge was deconstructed for storage at Ferrymead Heritage Park



15.02.12. Mowed quake cracks, Avon River bank, River Rd, nr Medway St Footbridge. Cracks due to lateral spreading


15.02.12. Quake trashed, abandoned house, River Rd, nr Medway St Footbridge

Gayhurst Rd Bridge: Concrete, 3 span. Spans OK. Road join slumped, Dallington Tce & Locksley Ave side, exposing pavement pipes & pavement ends. Abutment cracked, Dallington Tce & Locksley Ave side.

A Dallington Tce road closure sign read:

        TEMPORARY ROAD
                CLOSURE

DALLINGTON TCE CLOSED
BETWEEN 16 DALLINGTON TCE
     AND McBRATNEYS ROAD
   7.00am TUESDAY 7/02/2012
TO 5.00pm FRIDAY 24/02/2012

  24 HOURS FOR ENQUIRIES
       PH...

There were many road closure signs around Christchurch & we'd see many more over the next few years.

A sign on a power pole read:

R :)
ZONE
net.

Images, quake damaged Gayhurst Rd Bridge:


15.02.12. Gayhurst Rd Bridge, quake slumped road join, cnr Gayhurst Rd / Dallington Tce



15.02.12. Gayhurst Rd Bridge, quake cracked abutment, cnr Gayhurst Rd / Dallington Tce



15.02.12. Gayhurst Rd Bridge, quake slumped footpath by abutment, cnr Gayhurst Rd / Avonside Dr


15.02.12. Avonside Dr view of quake damaged Gayhurst Rd Bridge


15.02.12. Avonside Dr view of quake cracked abutment, Gayhurst Rd Bridge, cnr Gayhurst Rd / Locksley Ave


15.02.12. Gayhurst Rd Bridge view of quake trashed, abandoned housing, cnr Gayhurst Rd / Locksley Ave. The housing was demolished


15.02.12. Gayhurst Rd Bridge, quake cracked abutment & slumped road join, cnr Gayhurst Rd / Locksley Ave


Snell Pl Footbridge: Concrete, 1 arch span. Span spalled at downriver side of arch apex. Cracked concrete abutment, Avonside Dr side. Bridge fence cordon closed, with EXTREME DANGER sign. Snell Pl Footbridge was demolished.

Images, quake damaged Snell Pl Footbridge:


15.02.12. Locksley Ave view of quake slumped drain, Avon River bank, Avonside Dr


15.02.12. Snell Pl Footbridge, quake trashed, closed, between Locksley Ave & Avonside Dr. Snell Pl Footbridge was demolished


15.02.12. Snell Pl Footbridge, quake cracked abutment, Avonside Dr side


15.02.12. Snell Pl Footbridge, quake trashed, closed, Locksley Ave side. EXTREME DANGER. Snell Pl Footbridge was demolished


15.02.12. Snell Pl Footbridge, quake spalled, span arch apex, Locksley Ave side. Snell Pl Footbridge was demolished


Locksley Ave, Kerrs Reach: Avon Rowing Club bldg gone, demolished, opposite Avon River bank. Avon Rowing Club was rebuilt. Further on, parked by red zone houses, I watched an orange dredger & 2 City Care workmen dredging weeds from Avon River.

Images of quake damaged Locksley Ave:


15.02.12. Locksley Ave view of Avon Rowing Club, post quake, demolition site, Kerrs Reach, Avon River. Avon Rowing Club was rebuilt


15.02.12. Locksley Ave view of City Care, post quake, water weed dredging, Kerrs Reach, Avon River




15.02.12. Quake trashed, boarded house, Locksley Ave, Kerrs Reach

Avondale Rd Bridge: Concrete: 3 span. Spans OK. Abutments skewed Avonside Dr side. Road cracks across bridge at road joins. Patch repairs with yellow, hardened foam & tar seal at cracks.

In 2013 the bridge was repaired with abutments demolished & replaced. SCIRT took its time with repairs, so the bridge was closed for the whole of 2013. Never mind inconvenienced locals having to drive long detours. That was par for SCIRT's obstacle courses for years in post quake Christchurch.

Images, quake damaged Avondale Rd Bridge:


15.02.12. New Brighton Rd upriver view of quake damaged Avondale Rd Bridge


15.02.12. Avondale Rd Bridge, quake tilted abutment & spalled span end, New Brighton Rd upriver side. The abutment was demolished & replaced by SCIRT in 2013


15.02.12. Avondale Rd Bridge, quake tilted abutment & span end, Avondale Rd, downriver side. The abutment was demolished & replaced by SCIRT in 2013


15.02.12. Avondale Rd Bridge, quake tilted abutment & light poles, Avondale Rd, downriver side. The abutment was demolished & replaced by SCIRT in 2013


15.02.12. Avondale Rd Bridge, quake separated abutment, span & hand rail, Avondale Rd, downriver side. The abutment was demolished & replaced by SCIRT in 2013


15.02.12. Avondale Rd Bridge, patch repairs to join between abutment & span, Avondale Rd side


15.02.12. Avondale Rd Bridge, quake tilted abutment & patch repairs between abutment & span, Avonside Dr upriver side. The abutment was demolished & replaced by SCIRT in 2013


15.02.12. Avondale Rd Bridge view of quake survivor housing, New Brighton Rd


15.02.12. Quake road damage between Avondale Rd Bridge road deck & abutment, New Brighton Rd side




15.02.12. Avondale Rd Bridge, quake tilted abutment, span & hand rail, New Brighton Rd side. The abutment was demolished & replaced by SCIRT in 2013


15.02.12. New Brighton Rd downriver view of quake damaged Avondale Rd Bridge


15.02.12. Post quake, plastic, sewage tank, New Brighton Rd / Avondale Rd Bridge traffic circle

Anzac Bridge: Concrete, 3 span. Spans OK. Big bridge, heavy traffic. Nearby New Brighton Rd & Anzac Dr in bad, bumpy condition, due to waterway between Travis Wetland & Avon River.

Images, quake damaged Anzac Bridge:


15.02.12. New Brighton Rd upriver view of quake damaged Anzac Bridge


15.02.12. Anzac Bridge NE cnr, quake flooded cycle track, quake tilted abutment & spalled span




15.02.12.Anzac Bridge NE cnr, quake damaged abutment & plinth


15.02.12. Anzac Bridge, post quake upriver view of Avon River


15.02.12. Anzac Bridge NW cnr, quake damaged abutment & pavement join


Concrete cycle tracks below the bridge were quake trashed / flooded. There were deep cracks with small fish swimming in flooded quake cracks, south side. Cycle track concrete slabs were badly damaged, some 1 m high separations, New Brighton Rd side & Hulverston Dr side. Spalled concrete at cycle track edges, Hulverston Dr side.


15.02.12. Post quake road works, Hulverston Dr by Anzac Bridge


15.02.12. Anzac Bridge NW cnr, quake trashed / flooded cycle track



15.02.12. Anzac Bridge NW cnr, quake tilted abutment


15.02.12. Anzac Bridge NW cnr, car tyres below quake tilted abutment


Abutments skewed at odd angles, revealed masses of old rubber tyres dumped under abutments, amongst abutment supports. Lights & light plinths were skewed at bridge ends. Acute angle gaps between concrete span ends & concrete abutments.


15.02.12. Quake damaged New Brighton Rd nr Anzac Bridge



15.02.12. Anzac Bridge SE cnr, quake cracked abutment


15.02.12. Anzac Bridge SE cnr, quake cracked & spalled bridge piers


15.02.12. Anzac Bridge SE cnr, quake trashed / flooded cycle track & quake tilted abutment


Of 8 square concrete piers in the riverbed, supporting concrete spans, 2 square concrete piers had spalling & cracked concrete below spans. Those 2 piers could fail in the next big quake. Superficial spalling was at abutment edges.


15.02.12. Anzac Bridge SE cnr, quake trashed / flooded cycle track & quake tilted abutment


15.02.12. Downriver view of quake damaged Anzac Bridge

Anzac Bridge looked unsafe. I didn't want to be driving on Anzac Bridge during the next big quake, as downriver side, the 2 cracked & spalled piers in Avon River looked ominous.


15.02.12. Anzac Bridge SW cnr, quake tilted abutment


15.02.12. Anzac Bridge SW cnr, old tyres below quake tilted abutment


15.02.12. Anzac Bridge SW cnr, quake spalled concrete wall by cycle track


15.02.12. Anzac Bridge SW cnr, quake cracked & spalled piers


15.02.12. Anzac Bridge SW cnr, quake trashed / flooded cycle track & quake tilted abutment


Wainoni Rd Bridge: Concrete, 3 span. Spans OK. Concrete slab separations at light plinths & concrete barrier in middle of bridge, Wainoni Rd end. Downriver side cycle track slumped at abutment ends. Tar seal cycle track was sunk a foot in places below concrete cycle track, both bridge ends, due to abutments slumping. Distinct bow shape of concrete middle span of side cycle track. Nasty. I crossed the bridge on the pavement.

Images, quake damaged Wainoni Rd Bridge:


15.02.12. New Brighton Rd upriver view of quake damaged Wainoni Rd Bridge


15.02.12. Wainoni Rd Bridge, quake cracked light plinth, New Brighton Rd


15.02.12. Wainoni Rd Bridge, post quake patch between abutment & road deck, New Brighton Rd. See ski jump effect after post quake road repair


15.02.12. Wainoni Rd Bridge, quake damaged, part repaired cycle track, New Brighton Rd


15.02.12. Wainoni Rd Bridge, quake bent cycle track span, downriver side



15.02.12. Wainoni Rd Bridge, post quake downriver view of Avon River


15.02.12. Wainoni Rd Bridge, post quake cycle track, downriver side, Wainoni Rd


15.02.12. Wainoni Rd Bridge, quake slumped join between abutment & road deck, Wainoni Rd


15.02.12. Wainoni Rd Bridge, quake slumped / spalled cycle track above abutment, Wainoni Rd




15.02.12. Avon River stop bank, downriver view of quake damaged Wainoni Rd Bridge, Wainoni Rd


15.02.12. Wainoni Rd Bridge, Wainoni Rd view of post quake road patching on slumped abutment, aka ski jump effect


15.02.12. Wainoni Rd Bridge, quake cracked light plinth, Wainoni Rd


15.02.12. Upriver view of quake damaged Wainoni Rd Bridge, Wainoni Rd



15.02.12. Quake trashed house nr Wainoni Rd Bridge, New Brighton Rd. The house was demolished


Pages Rd Bridge: Concrete, 3 span. Spans OK. Tar seal cracks across bridge at road joins both sides. Superficial stonework cracks at abutments on Owles Tce side & Wairoa St side. Deep quake cracks on riverbank, Owles Tce side, due to lateral spreading. Wairoa St side, quake cracks on riverbank, were stop bank shingle repaired.

Images, quake damaged Pages Rd Bridge:


15.02.12. New Brighton Rd upriver view of quake damaged Pages Rd Bridge


15.02.12. Pages Rd Bridge NE cnr, post quake road works



15.02.12. Road island view of quake damaged Pages Rd Bridge, New Brighton side


15.02.12. Pages Rd Bridge SE cnr, quake damaged abutment & slumped Avon River bank, due to lateral spreading



15.02.12. Pages Rd Bridge, post quake, plastic, sewage pipes


15.02.12. Pages Rd Bridge downriver view of Avon River. Owles Tce left, raised stop bank by Wairoa St right


15.02.12. Pages Rd Bridge SE cnr, abutment & wing wall quake damage, Owles Tce side


15.02.12. Pages Rd Bridge SW cnr, abutment quake damage, Wairoa St side


15.02.12. Pages Rd Bridge SW cnr, abutment & road patch repairs, Wairoa St side, aka ski jump effect



15.02.12. Pages Rd Bridge SW cnr, abutment quake damage, Wairoa St side, aka ski jump effect


15.02.12. Wairoa St stop bank, downriver view of quake damaged Pages Rd Bridge


15.02.12. Pages Rd Bridge NW cnr, post quake road works

South Brighton Bridge: Concrete, 3 span. Big bridge. Spans OK. Spans supported by rubber blocks between spans & piers & between span ends & abutments. Quakes horizontally rotated spans & road deck in a clockwise direction, so that the NW corner span deck stuck out northwards from the bridge, away from the abutment & the SE corner span deck stuck out southwards from the bridge, away from the other abutment.

Images, quake damaged South Brighton Bridge:


15.02.12. Avon River Estuary view of South Brighton Bridge. Port Hills back drop



15.02.12. Bridge St view of Avon - Heathcote Estuary. Mt Pleasant, Mt Cavendish, Port Hills back drop


15.02.12. Bridge St upriver view of Avon River Estuary, looking towards New Brighton

Post quakes, as Bridge St was misaligned with South Brighton Bridge road deck, when driving across one had to snake across at bridge ends.


15.02.12. South Brighton Bridge NE cnr, quake broken, warped hand rail, Bridge St, due to horizontal clockwise rotation of bridge spans. See the NE cnr rotated the width of a tyre tread


15.02.12. South Brighton Bridge NE cnr view of SE cnr & quake shifted span & road deck, Bridge St


15.02.12. South Brighton Bridge NE cnr, quake split hand rail & southwards shift of span & road deck, Bridge St, due to clockwise rotation of span & road deck


15.02.12. South Brighton Bridge NE cnr, quake tilted abutment & shifted span, Bridge St


15.02.12. South Brighton Bridge NE cnr, upriver view of quake shifted spans, Bridge St

Rubber support block crushed? lost? from under the span end at the SE corner join between span end & abutment. Plugged with 2 wood planks. (What were engineers taught at varsity?)


15.02.12. South Brighton Bridge, NW cnr view of quake split & warped hand rail & northwards shift of span & road deck, Bridge St, due to clockwise rotation of span & road deck


15.02.12. NW cnr view of clockwise rotation of bridge span with northwards shift of span & road deck


15.02.12. South Brighton Bridge NW cnr, upriver view of quake shifted spans, Bridge St


15.02.12. South Brighton Bridge NW cnr, quake split hand rail & northwards shift of span & road deck, by quake cracked abutment, Bridge St


15.02.12. South Brighton Bridge NW cnr, quake damaged & shifted span & abutment, with exposed abutment supports, Bridge St


Concrete span & road deck at NW end of bridge had moved the most, about 2 feet northwards & diagonally opposite SE span & road deck had moved about 1 foot southwards - estuary mouth direction. Clockwise rotation direction was easily seen at the road joins above.


15.02.12. South Brighton Bridge SW cnr, view of NW cnr & northwards shift of span & road deck, Bridge St


15.02.12. South Brighton Bridge SW cnr, post quake sewage pipe & quake split hand rail, Bridge St, showing clockwise rotation of road deck away from abutment hand rail


15.02.12. South Brighton Bridge SW cnr, mangled rubber lining between span road deck & abutment & northwards, quake shifted span & road deck, Bridge St


15.02.12. South Brighton Bridge SW cnr, downriver view, quake tilted abutment & quake shifted span & road deck, Bridge St


15.02.12. South Brighton Bridge SW cnr, quake displaced rubber block, below span, plugged by wooden planks, by quake tilted abutment, Bridge St


15.02.12. South Brighton Bridge SW cnr, downriver view of quake shifted bridge spans, Bridge St

Abutments at both bridge ends were skewed, with acute angles between span ends & abutment joins. Rubber block was displaced from join between abutment & span end at SW corner of bridge. Plugged with 2 wood planks again!


15.02.12. South Brighton Bridge SE cnr, quake moved span & deck southwards away from abutment, Bridge St, due to clockwise rotation of spans




15.02.12. South Brighton Bridge SE cnr, quake split & warped hand rail, post quake sewage pipe & southwards movement of span & road deck, Bridge St, due to clockwise rotation of spans


15.02.12. South Brighton Bridge SE cnr, quake moved span & abutment, Bridge St


15.02.12. South Brighton Bridge SE cnr, quake moved span & road deck, angled away from abutment, rubber block gone, Bridge St




15.02.12. South Brighton Bridge SE cnr, quake moved span & road deck, above abutment supports, Bridge St



15.02.12. South Brighton Bridge SE cnr, downriver view of quake shifted spans, Bridge St



Metal hand rails at 4 corners of the bridge were split & warped by bridge movement. Rubber linings between abutments & road joins were twisted & mangled at the road surface.


15.02.12. South Brighton Bridge NE cnr, quake split hand rail, Bridge St


15.02.12. South Brighton Bridge, quake split hand rail, centre of upriver span deck, Bridge St


15.02.12. South Brighton Bridge NW cnr, upriver span deck, quake moved northwards, Bridge St, due to clockwise rotation of spans


15.02.12. South Brighton Bridge SW cnr, quake split handrail & post quake sewage pipe, Bridge St


15.02.12. South Brighton Bridge SE cnr, quake split hand rail, post quake sewage pipe & downriver span deck, quake moved southwards, Bridge St, due to clockwise rotation of span & road deck


15.02.12. South Brighton Bridge SE cnr, quake moved span deck & road southwards, Bridge St


15.02.12. South Brighton Bridge SE cnr, quake split & warped hand rail, post quake sewage pipe & quake rotated span & road deck southwards, Bridge St


Lovely southern view of Avon River Estuary & Port Hills. Quake trashed, Pleasant Point Yacht Club was gone, demolished.


15.02.12. South Brighton Bridge view of Avon - Heathcote Estuary & Pleasant Point Yacht Club demolition site. Port Hills back drop



Although South Brighton Bridge looked reasonably OK after 10 000 quakes & patch repairs, with all the quake twisting, tilting & shifting of bridge structures, the steel reinforcements were under great stress, awaiting failure in the next big quake.

As the Alpine Fault, 100 kms away, hadn't ruptured for decades, pundits said it would shake Canterbury for 2 minutes straight, much longer than any of the Christchurch quakes over the past 17 months.

Over the past couple of weeks, I'd looked at 14 Avon River bridges, from Manchester St Bridge in the CBD red zone, downriver to South Brighton Bridge over Avon Estuary. All were quake damaged.

Like the Feb 22 quake collapse of northbound Fitzgerald Ave beside Avon River, between Bealey Ave & Kilmore St, future quake collapse of any road bridges downriver from Christchurch CBD would cause traffic mayhem. Quake damage & weakening by 10 000 quakes did not bode well for Avon River bridges.

Why were engineers & Council allowing damaged bridges to be used still, with just patch repairs? Reminiscent of patch repairs done to bldgs before the lethal Feb 22 quake. Never mind disaster access & egress by eastern suburb residents. Nor tsunami danger if an offshore fault ruptured.

Thurs 16.02.12. 4.13 am, 4.1 mag quake, 5 km depth, 10 km E of Christchurch (Geonet). Slept through it. Quake savvy even in my sleep. Used to wake up during any 4 mag+ quakes in the night.

Thurs 23.02.12. I drove across South Brighton Bridge again. The south side lane was road cone cordoned, making the bridge one lane only, with mobile traffic lights each end of the bridge. As it was a year post Feb 22 quake, it was about time Council engineers jacked up their shonky bridge spans!

That same evening near St Bedes College one of my Honda Civic's new tyres had a blowout. First blowout I had in nearly 17 years living in Christchurch. Rotten fixing of quake trashed roads by Council.

The times when I looked at quake damaged, Avon River bridges was an interregnum between Council & CERA forming SCIRT, which would take years to repair quake trashed infrastructure, roads & bridges.

Coda. Christchurch Mail, 16.08.12, reported on Avon River bridge repairs by SCIRT:

South Brighton Bridge would be repaired - taking about 3 years to repair by April 2015.   

Pages Rd Bridge: "Repairs will begin when Bridge St Bridge (sic) is completed."

Avondale Rd Bridge: "Work has recently started."

Gayhurst Rd Bridge: "Early next year."

Anzac Bridge. "Mid 2013."

Why did infrastructure authorities, Council & SCIRT, dither doing repairs, while citizens were forced to use dangerous bridges for years?

Content & pics Copyright Mark JS Esslemont.

See Bridge St Bridge Repairs (SCIRT).



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