Post-IMF Road Design Standards

jd

blacktopper wrote: »

If we ignore the falling traffic but follow present NRA predicted growth as per appendix 6 we show traffic growth as per below:



We never get to the max capacity threshold of S2. This is what got me interested 6 months ago. What would your initial thoughts be if you were me?

Hi Blacktopper,
That counter is the nearest to Rosslare portt. What are the counts for south of Oylegate on the Wexford by-pass? I presume they are close to the max threshold of s2

blacktopper

MYOB wrote: »

1988 comes to mind without doing any searching; my boyfriend hails from Wexford so I'd hope to be right on pain of death...

Sorry for calling you Mr. MYOB etc. etc.

Its not incorrect though...

We'll bugger me if I've not got in wrong again Mr. MYOB red cheeks all round

Unacceptable comment; infracted - MOD

L1011

blacktopper wrote: »

We'll bugger me if I've not got in wrong again Mr. MYOB red cheeks all round

Rather childish, don't you think?

blacktopper

Sorry again MYOB. I was just trying to be friendly and everything I say seems to upset you. I shall restrain myself in future.

blacktopper

jd I did the excel for the Gorey South counter it still never reaches the max. capacity for S2:



Don't forget that is using the NRA's excessive 2-3% annual growth forecasts in appendix 6 of the Project Appraisal Guidelines and a max. capacity for an S2 road that you can double to get the UK equivalent capacity. Hmm. now where's the money on that one? Ah here it is, value of time savings. Oh no, they've gone down too. Maybe accident savings? No, accidents are down on that road and in general due to RSA/Garda enforcement. Oh I know I'll build it because its a Euro Route. Oh no can't do that either they already think its up to adequate standard. I'll just build it because I can. Ah that's better who ever needed a logical reason anyway.

Interpolating sure or mid-sized road no problem, a whole new 2+2? Where is the value?

jd

What's the aadt on the Wexford by-pass?

jd

jd wrote: »

What's the aadt on the Wexford by-pass?

Found the figures myself in the constraints study



What would be best with those traffic figures?

L1011

blacktopper wrote: »

Maybe accident savings? No, accidents are down on that road and in general due to RSA/Garda enforcement

Accidents are down on that section because it is now a motorway, not because of enforcement. It only opened in ~2007 so any earlier figures refer to the former N road through Clogh....

blacktopper

Jd we both know what would be best with those figures. It was those figures that got me started. They are wrong. I produced this 6 months ago it was my very first bit of work. I read the constraints carefully and questioned it in its 4 main drivers. I now have a lot more work so I'll drop this in:

Evaluation of N11/N25 Wexford Town Bypass Desktop Feasibility Study contained in N11/N25 Oilgate to Rosslare Harbour Road Improvement Scheme Constraints Study Report August 2009:

For the purpose of the desktop study, the road between Oilgate and Rosslare Harbour was split into 3 sections. The first section between Oilgate and the Ferrycarrig Bridge was modelled using a single data set from counts taken at one point in the road in 2004 (N25-4) Wexford 12.22 JN MINOR RD TO CASTLE-BR) by manual traffic counts. From this single data set, at that time, 5 years in the past it was deemed possible to predict the traffic volumes between the Ferrycarrig Bridge and Oilgate along the N11 split into 3 segments. Not only was this isolated 1 point of counting out of date set of data used to predict present day traffic volumes stretched out over 3 separate segments of the road. It was further considered appropriate to then predict on to 2020.

The 2004 traffic count position on the road between the Ferrycarrig Bridge and Oilgate that best corresponds to this artificial 3 segment split in the desktop study is segment 1.

Rather than make multiple assumptions that are required to develop a model of the network from 2004 data to predict into the future a single assumption is made that the relationship between traffic in 1 part in a small network and another remains constant over time, and used to predict traffic in 1 part of the network from known values in another part for that year. An example is given below, working with factual data recorded between 2001 and 20041 and also 2007 and 2010 and extrapolating to 2007 and 2010 in uncounted segments of the road.

Key For All Tables:

normal print = true gathered data from counting traffic.
bold print = estimated values calculated from models.



A further example:

For the purpose of the desktop study, the road between Oilgate and Rosslare Harbour's second section consisted of the present Wexford Bypass i.e. from the southern end of the Ferrycarrig bridge to the Rosslare roundabout.

Using the 2004 traffic count position of the New Ross Roundabout (roundabout at N25 /N11/R769) that corresponds to section 2 segment 4 in the Desktop study of the constraints report:



These estimates are at variance to those predicted in the desktop model and far more modest, see tables below:






They are more likely to be predictive as they use fewer assumptions in their generation and use up to date data in their generation. They also reflect better the true growth in the network shown from the Automatic Traffic Counter Statistics that have produced true traffic values from 2004 to 2010, see table below:



From this table of true gathered data it is evident there has been a reduction in traffic between 2007 to 2010 this has been observed across the Irish road network. A comparison of this true reduction and the estimates produced by the desktop model and the simple method of traffic calculation shown here further highlights the inaccurate predictive power of the desktop model in the constraints report:

True growth in traffic volumes Rosslare N25 immediately east of Kilrane (N25-1), 2007 - 2010 = -12.6%

True growth in traffic volumes Carrigbyrne N25 east of Ballynabola (N25-10), 2007 - 2010 = -9.3%

True growth in traffic volumes Gorey South N11 N11 between Clogh roundabout and Raheenagurren interchange (N11-10A), 2007-2010 = -2%

Estimated Growth (Calculated by method table 1) JN MINOR RD TO CASTLE-BR
(N11-4), 2007 - 2010 = -12.6%

Estimated Growth (Calculated by Desktop model) JN MINOR RD TO CASTLE-BR
(N11-4), 2007 - 2010 = +10.6%

Estimated Growth (Calculated by method table 2) RO WITH N11 AND R769
(N25-6), 2007 - 2010 = -12.6%

Estimated Growth ((Calculated by Desktop model) RO WITH N11 AND R769
(N25-6), 2007 - 2010 = +10.6%

Thus we can see that the flaws within the desktop model result in it predicting inexorable increase in traffic volumes. On the other hand the comparative method using limited assumptions and known data shows a decrease in traffic volumes comparable to true data collected locally and across the Irish road network as a whole. I cannot understand how a road engineer who would have had common knowledge of the phenomenon of year on year reduction in nationwide traffic volumes, in recent years, and the same data shown here with which to check the predictions of his/her traffic model continued to produce a model the predicted year on year growth and massive estimates of traffic.

There is only one point along the section of road N11/N25 Rosslare - Oilgate that factual traffic data has continued to be collected with which a true comparison between the predictions of the desktop study and actual counted data could have been made. That is the automatic traffic counter at Rosslare N25 immediately east of Kilrane (N25-1). It is notable that this is the only set of traffic volumes that:

• No run of the desktop study was made ,that has been used to predict all other traffic volumes in the study, for 2007 and 2009. Possibly because it would highlight the glaring overestimations the desktop study produces.
• This is the only point along the route between Rosslare - Oilgate where sub 10,000 AADT traffic volumes are predicted and reducing year on year traffic volumes.

The Wexford council constraints report thus developed a premise for requiring this road scheme.

I have repeatedly asked for the latest traffic count study on the present road I have been refused. Empirical observation is better than prediction.

Stop focusing on my pet road. There is more at stake here. We're in the economic ****. Lets do our bit to dig ourselves out. Come on people put aside your dislike of people like me and work on this project. Lets give the road builders something that might be useful. You guys live and breathe roads you can produce something of value.

blacktopper

MYOB, accidents are down on the N11/N25 between Rosslare and Oilgate the one that is being replaced?? If accidents are down that's basically the other 16% of the benefits in the CBA that need to be revised. Stop worrying about my road, I'll worry about that. This thread is a productive one. Please consider how we can change the DMRB to save money. I keep on about it - Value - VALUE - VALUE.

If anyone thinks the NRA should become responsible for more roads, that is OK too. The low cost remedial works scheme has been shown to produce annual rates of return of 502%. Getting one coherent authority to prioritise the whole network by some logical set of criteria then overseeing work to build a coherent network would be logical. The scheme only gets enough funding annually to build about 1Km of motorway. Now we all drive these roads everyday so does the next Minister of Transport. If the NRA could develop a proposal for this and develop a "lower cost alternative"/"do something else" option for roads whose capacity is in the mid-zone. Then it will have gone a long way to doing its bit for the country. I'm talking sense here, you know I am.

Sponge Bob

Very Interesting, do go on. Traffic is not reducing everywhere though.

Also remember that with the existing junctions at grade a lot of Wexford Bypass traffic is made up of local junction hoppers. Grade separation would reduce that.

One thing the NRA has not done is design 'midlife remediation packages', this would be where a new road is not designed but some small bypasses and grade separations ( and the odd primary school relocation) takes sufficient traffic off a STRETCH of road that the upgrade issue can be kicked over 10 years down the line. This requires that all the measures are implemented in full in one contract in order that maybe 30 or 40km of road is dealt with ...not just a few right hand turns and crossroads.

I would give them school building on Primary routes and in their contigous corridors up to 5km away so

blacktopper

Always glad when you post Sponge.

The 'midlife remediation packages' is exactly the concept I think we should be looking at in the present time. It is already implicit within the NRA guidelines, so I guess if options like that were to start popping up then it would certainly show a desire to search hard for value for money management options already available. Such planning striving to pull every ounce of value out of an existing road should be commended.

Are you talking about relocation of public buildings like schools that have already reached their life-expectancy and have been or will be granted funding to rebuild, to locations where roads are less trafficked? This sounds like a very sensible win, win situation. Children are not coming out onto busy roads with inherent dangers also the effects of noise and air pollution during the school day will be dramatically reduced. Parents collecting are not competing with commuter and commercial traffic to go and pick up and drop off. Commercial traffic is equally not competing with mums and dads on the same stretch of road. Brilliant idea, you should be a road designer.:D

jd

blacktopper wrote: »

The Wexford council constraints report thus developed a premise for requiring this road scheme.

I have repeatedly asked for the latest traffic count study on the present road I have been refused. Empirical observation is better than prediction.

Ok, I'll have to agree with you there . I'd like some empirical data rather than extrapolations etc.

blacktopper wrote: »

Stop focusing on my pet road.

I'll keep it to another thread. Of course, it may be my pet road too!

Sponge Bob

blacktopper wrote: »

Always glad when you post Sponge.

The 'midlife remediation packages' is exactly the concept I think we should be looking at in the present time.

Are you talking about relocation of public buildings like schools that have already reached their life-expectancy and have been or will be granted funding to rebuild, to locations where roads are less trafficked?

Where we have a substandard S2 we should bundle the problems together. The NRA has had a huge impact with their right hand turn filter retrofits.

One final problem is that there are many schools along major routes. Get them off. This may mean giving part of the school building program to the NRA.

Therefore the continuation of filter installations together with relocation of schools off primary roads and some selective grade separations would have a significant impact on safety and speeds on _certain_ stretches but not requiring land takes and offline corridors.

I do not recall the road from North of Enniscorthy to Rosslare being absolutely hideous and a remediation package for that Entire route may deliver speed and safety improvements of note.

I am on record here as saying that I could live with the N17 north of Tuam to Curry as long as that long bad bend in Castletown and the Ballindine - Milltown stretches were done. Around and south of Tuam has too much traffic, period.

That would leave the Cooloney - Curry stretch as the next priority offline project. Someone was even killed the other day on that stretch, just after I passed by

It is impossible for a reasonably competent driver to do more than a steady 80kph on that road and that assuming low traffic, any commuter traffic or trucks only worsen the situation. It cannot be remediated, only bypassed.

What I do want from the NRA is the certainty as to whether a (say) 30km route is scheduled for upgrade or remediation. The when is another matter entirely.

Sponge Bob

I see this thread died a death before any systemic designs were proposed. May as well lock it up as an artefact mods

blacktopper

I agree, best to post on "the NRA must be stopped" thread. Seems to get more response and is place most likely the general public will look at. Shame no great ideas for saving money on roads are out there. This thread can remain in perpetuity to demonstrate that. I have directed a local guy to me who has become more interested in infrastructure of recent days to it already, it serves my point. I fear the road building industry in Ireland unless it can layout an innovative affordable new vision will be having lean times the next 10 years or so. Still all those road builders and fans who have to gain work in other countries can still keep in contact on Boards.ie so its not all that bad. Still a shame nobody took up the challenge.

Sponge Bob

Be nice if the forum becomes a social gathering of former road engineering types with the sweet permawhiff of hot asphalt about . Won't get us anywhere though.

blacktopper

I tried Spongebob. It is not easy sitting on this board when you have my point of view and it took a lot of my time but apart from yourself and a few other contributions I got little for it.

L1011

Sponge Bob wrote: »

I see this thread died a death before any systemic designs were proposed. May as well lock it up as an artefact mods

Most likely because anyone with the interest to propose a design accepts that we already have the required standards in the spec book.

blacktopper

Its a shame MYOB because a lot of road builders will be living abroad with that attitude, but of course your entitled to it. I wonder if you saw the latest road improvement on the Welsh A40 Slebech to Penblewin. Their design and appraisal team argued for WS2+1 against the local request for dual carriageway over a short 4.4km stretch just on the other side of the water in Ireland the design team will have none of it and wants 2+2 for 35km. Now who do you think has more chance of sitting down with their family for Sunday lunch for the next 5 years those guys in the Highways Agency or you. Gives you pause for thought.

blacktopper

By the way MYOB you should pull all the documents on that road its a mirror for the Rosslare-Oilgate N25/N11 scheme. Boy do they go to town justifying a 2+1. It had me convinced.

dubhthach

Have any 2+1 roads been built in Wales before? They were built here and have been shown to be a safety risk. The cost of a 2+2 instead is about circa 10% more and considerably safer.

L1011

blacktopper wrote: »

Its a shame MYOB because a lot of road builders will be living abroad with that attitude, but of course your entitled to it. I wonder if you saw the latest road improvement on the Welsh A40 Slebech to Penblewin. Their design and appraisal team argued for WS2+1 against the local request for dual carriageway over a short 4.4km stretch just on the other side of the water in Ireland the design team will have none of it and wants 2+2 for 35km. Now who do you think has more chance of sitting down with their family for Sunday lunch for the next 5 years those guys in the Highways Agency or you. Gives you pause for thought.

Once again, if you actually knew anything about roads, you'd know that 2+1 is extremely dangerous, cannot be made safe and costs fractionally less than 2+2.

Using UK prices - which are for entirely different classes of roads - to pretend it costs significantly more - is a fallacy.

Your sudden pro-rail push is effectively a coming out. We're now seeing the real reason you're anti road.

blacktopper

Yeah that's right the Brits know nothing about roads and they like killing their people. You guys aren't the brightest tools in the box now are you. Oh and the Germans use 2+1 as well , er and the Swedes - yep you found them all out their all silly buggers killing off their own people. Thank good for you idiots for showing them the way. We'll done fellas maybe you could tell me the cure for cancer next because you sure seem to think you know it all.

L1011

blacktopper wrote: »

Yeah that's right the Brits no nothing about roads and they like killing their people. You guys aren't the brightest tools in the box now are you.

The Brits have worse per mile driven road deaths than we do.

They also have 70mph limits on old dual carriageways with no central barrier (just a grass strip) and crossing traffic and other such wonders.

Again, you know nothing about roads. Here or the UK, where you try and use figures from.

blacktopper

Regarding Rail being the new roads got that from a chat from these guys:

European Commission
Directorate-General for Energy and Transport
Directorate B — Financial Team
DM24 — 08/12
Rue de la Loi/Wetstraat 200
B-1049 Brussels

I wanted a medium sized road option you gave jack I went a hunting and guess what I found:



That is where the funding is going to be going. Now don't shoot the messenger, much though you'd like too.:D

L1011

We aren't going to be getting EU funding for infrastructure for the forseeable future so you can believe what you want.

Also, I call troll on you at this stage.

blacktopper

You don't get it do you. I posted here to demonstrate ideas for affordability or lack of them for roads. The project is over the natural conclusion therefore is to follow Europe see the picture above. Thanks.

BTW I started this thread so how can I be a troll.

BTW the facts about road deaths etc get your facts straight.

BTW funding for transport depends on mode and which "envelope" it comes from. Your right the road one is practically empty, once again not me saying this it is EU.

L1011

blacktopper wrote: »

You don't get it do you. I posted here to demonstrate ideas for affordability or lack of them for roads. The project is over the natural conclusion therefore is to follow Europe see the picture above. Thanks.

I get it completely:

*You posted here to try and insist that 2+2s were effectively motorways and far more expensive than wide single carriageways. You got proven horribly wrong, though you denied it to the hilt
*You then discovered 2+1s and decided they were the best thing since sliced bread, and decided to push them as much as possible - despite them being dangerous and obsolete
*You then decided to become a rail troll.

blacktopper

You get nothing MYOB.

My original premise was we must find a road we can support we must start to work in partnership and compromise we must work for the economic good and possibly accept less than what we would previously.

I pushed hard to get sanction on that but had to achieve certain goals for an acceptablility.

Luckily you guys are not the final arbiters on this. But if your anything to go by your to closed minded and stuck in the boom to be of any use. A few years in the budgetary wilderness may change you. The economics of this is, due to recession we only need to keep up a small amount of investment in roads to actually come out of this without an infrastructure deficit like the 80's. To get investment road methods will have to become more pragmatic, gold plated schemes affecting one county won't pass the test. I hope those with the real power not you or I are more realistic because your attitude is just the sort of stuff that will get road projects side-lined for 10-15 years. Think about it will you. You've seen the picture above, that is the fashion. If you want that keep on spouting the same old dogma. If you think road investment is still the answer for this Country change how you work. I shall not be tempted to post again MYOB I humbly ask you to reconsider that is all, I'm sorry I failed to persuade you I will accept defeat on that. I will not give up so easily on the Country my fight is elsewhere. Goodbye.:)