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CEO urges infrastructure investments that deliver jobs |
February 26, 2009 |
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Posted by Joseph Taylor at 12:32 PM | Comments (0) |
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Len C. Rodman, Chairman, President and CEO of Black & Veatch, said today that stimulus funding in energy, transportation and water infrastructure will provide the greatest returns in achieving U.S. economic recovery, job growth, greater efficiency and productivity.
In a column issued today, Rodman stated that longer-term investments in foundational infrastructure are needed to provide a more stable base of employment and sustainable benefits. The column “Spending Should Target Infrastructure That Repays Massive Investment” is available, click link.
“The goal of investing in the nation’s infrastructure as part of the economic recovery deserves widespread support and quick action,” Rodman said. “And we must look beyond simple U.S. roads and bridge infrastructure investments if we are to realize a wide-ranging and sustainable economic rejuvenation.”
In the column, Rodman explains how funding in such sectors as mass transit, railroads, energy and water not only helps jump-start and sustain the U.S. economy, but also leads to improvements in efficiency and better utilization of vital infrastructure. In addition, Rodman advises that such investments will bolster the basic construction industry as well as technology and manufacturing industries where the use of equipment that supports these needs drives a much wider base of the economy.
“In the long-run it’s critical that the country gain competitive advantages that are part of the solution to repay the massive debt we are incurring,” Rodman said.
Len C. Rodman
Black & Veatch
http://www.bv.com/
Can you afford not to use "Predictive Maintenance" for water and wastewater assets? |
February 08, 2009 |
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Posted by Steve Carson at 05:44 AM | Comments (5) |
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As asset management of wastewater collection systems and water supply systems has become more important, every utility wants to know the state of their assets.
For some types of assets, making the assesment is very easy - although it might be a sobering one. For example, the assessment of pipes and wells - the civil infrastructure that makes up a significant proportion of the utility's asset base. It's not so hard to figure out whether this asset class needs replacement, even though there is some work in the investigation.
The problem for wastewater utilities is that often the pipe network is 100 years old and so corroded that the whole pipe network needs replacement -and it's the largest asset class in terms of replacement value.
Pumps, Motors and Control Systems
But what about pumps and motors - and control systems?
The question "How do you maintain pumps and motors?" strikes at the heart of this problem. There are really three approaches to the problem:
- "Run to fail", i.e., wait until the pump or motor fails and - usually - race out and fix it or replace it
- Preventive maintenance, i.e., periodic maintenance of a pump or motor to avoid waiting for it to fail
- Predictive maintenance - the utility determines the state of each asset and can plan for servicing or replacement of a pump or motor
The majority of wastewater organizations in the USA have adopted a "run to fail" approach, although usually due to lack of resources and not with the perspective that this is the best way to reduce "whole of life" cost.
A significant proportion have adopted preventive maintenance, although when questioned, they are usually very open about the problem they have in understanding whether they are doing too much maintenance - or too little. Frequently, when we ask the question about their maintenance schedule we get the question back:
"So what does everyone else do?"
The UK, by comparison, has been trying to adopt a much more proactive approach, generally known there as Condition Based Monitoring, which in practice is the same as Predictive Maintenance.
The problem is really one of data, but, like any challenge, there has to be a motivation for doing something different.
Where is the data?
The most typical wastewater collection and water supply systems have very limited data for remote sites.
At a tradeshow a few months ago I was talking to the capital works manager of a wastewater utility with about 30 lift stations. I asked him how he planned his capital works program - how did he decide where to put his resources? His answer:
"It's all based on hours run"
His non-verbal response indicated that he wasn't comfortable with the approach. And when I followed up with a few other questions, he did say that he really felt the organization was flying blind.
However, the problem for this utility, as for so many others - the data just isn't there. The field devices aren't collecting enough data and the SCADA system isn't producing any reports that asset managers, utility directors and operations managers can use for proactive maintenance.
What Predictive Maintenance data can I get?
What is available for pumps, motors and control systems?
- Insulation Resistance of motor windings - leading indicator of 50-80% of motor burn outs in submersible pumps
- Flow - pump flow rates indicate whether impellors need servicing, and total station volume and inflow per station give system wide metrics for capital works
- Pump efficiency - volume per cost of energy, indicates ROI on replacement or servicing of pumps and impellors
- Detailed pump fault data - the respective totals of specific fault conditions provides leading indicators of problems
- Vibration analysis - only usually cost-effective on the larger pumps
All of this data is now easily available in Pump Station Managers - although to get vibration data, of course, you need the sensors. The other data is available from pump station managers without any additional equipment or sensors - view more information on the MultiSmart pump station manager.
The Organization still needs to be reactive!
It's important to understand that adopting predictive maintenance strategies doesn't mean that every failure will be known in advance. Failure of components in a system - regardless of the actual system - is governed by random factors. We see these random factors as statistics! One in one hundred failed! One in one thousand failed!
Statistics and random failure might be the subject for another day, but the important point is you still have to retain a responsive organization for when a pump fails at 2am on Sunday morning.
The Benefit
The benefit you have with condition based monitoring or predictive maintenance is that you can now have a lot more confidence of the state of your assets and you run your maintenance program more proactively and most cost-effectively.
You can say - confidently - that you are not running your pumps and motors into the ground. Or you can say - confidently - that the organization has almost run its assets into the ground! Let's hope it's not this one!
And based on the real state of the system, you can plan the most effective capital works, replacement or servicing program.
I often use the analogy of a business. If you don't know whether you will make a profit or loss this year, your stakeholders won't think you are looking after their interests.
If you are looking after critical infrastructure you don't want to find that 2009 is the year when all of your pumps started failing and your energy costs went up 10%!
Steve Carson
MultiTrode
MultiTrode is the specialist in control and monitoring for lift stations, and also runs a Lift Station Technology Blog
Shepherding Water: Unregulated water allocation and management |
February 04, 2009 |
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Posted by Joseph Taylor at 10:45 AM | Comments (0) |
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“Careless shepherd make excellent dinner for wolf.“ Earl Derr Biggers
In regulated water supply systems like the River Murray, when you want to use some of a seasonal allocation made to your entitlement, you order it. In the meantime, the balance of the water allocated to you is stored for you in one or more large dams.
In unregulated water supply systems, however, there are no large dams and access to water is reliant on capturing water as it flows past your place and storing it in your own dam. In addition to river flow, significant amounts of water can sometimes be obtained by capturing overland flows – especially in extremely episodic systems like those found in Australia’s Darling River system.
Apart from a few licences to take water from waterholes or weirs, when the flow rate is low no-one is allowed to take water. As the flow rate increases and defined flow-rate thresholds are passed at a defined point, progressively more and more licence holders are allowed to extract water from the river and/or allowed to harvest overland flows.
To prevent over-harvesting, flow-rate threshold announcements are usually made on a daily basis and, for each threshold, entitlements specify a maximum daily volume that may be diverted or taken while the river flows above that rate. In some systems, maximum storage volume limits are set.
The resultant management regime can be extremely complicated. In Queensland’s Lower Balonne system, for example, most entitlements or licences, as they are often called, contain two or three flow-rate thresholds. Larger licences may contain more than 20 flow-rate thresholds.
As a general rule and given the rate at which new technologies and new markets have emerged, there is no logical reason to assume that the current assignment of these opportunities to take water from an unregulated system is optimal. Thus in most systems, there is a case for allowing people to trade their licence from one location to another.
In unregulated systems and when the flow is episodic, how can trading be facilitated? If one wanted to reduce the take of water from one part of the system or “shepherd” water to the end of the system, what administrative arrangements would need to be in place? What is the best way to deal with the effects of shifts to a drier climatic regime and/or preference for environmental outcomes?
Sharing the available water
When setting up an unregulated entitlement and trading system, careful consideration must be given to the likely impacts of each trade on downstream wetlands, downstream entitlement holders and the interests of landholders whose animals graze on floodplains that have traditionally been wetted by overland flows.
The interests of towns may also need to be taken into account. In some New South Wales systems, for example, river managers are required to take into account both the flow rate at a defined point and the amount of water in the Menindee Lakes, from where Broken Hill’s water supply is drawn.
To fulfil these downstream requirements and obligations, managers need to be able to time announcements in a way that enables water to be shepherded past licence holders otherwise entitled to take this water.
Trading
If, however, a river system is divided into a number of reaches and each entitlement is defined by the flow rate at the top of the reach, the maximum amount that one licence holder can take within the reach is not changed by the actions of all other entitlement holders in the reach. Under such as regime, and with appropriate adjustment to account for downstream interests, within-reach trading is possible. But to trade from one reach to another, it has to be possible to raise or lower the flow rate at which the announcements are made.
Accounting for transmission losses
In most unregulated systems, especially those that spread out over large areas, transmission losses can be high. This means that whenever an entitlement is traded, the main factors that determine how much water can be taken – like the maximum pumping rate – may need to be adjusted. In most systems, computer models have been developed and used to estimate the changes that are likely to occur and make an appropriate adjustment to the maximum pumping rate. In practice, however, such models are far from perfect. In the short-term, the easiest way around this problem is to set a conservative exchange rate.
An alternative approach is to allow tagged trading. Under a tagged trading regime, the purchased entitlement retains all of its characteristics at its original location. The amount that can be taken at the new location is then adjusted periodically to take account of changes in conditions at the original location and knowledge about the behaviour of the system. Tagged trading systems are designed to protect the long-term interests of third parties. They do this by assigning the exchange rate risk to the buyer.
We think that the development of a tagged trading system for unregulated system management has merit – especially when the volumes involved are so large that they may change the pattern of water flow across the landscape. Tagged trading in unregulated systems has particular merit when river managers are uncertain about the impact of a trade on the direction of water flow across a landscape. With further development and improvement of modelling, eventually normal transfer of a purchased entitlement to another location should be possible.
When one moves the pumping or diversion point upstream, the interests of other pumpers, landholders who benefit from grazing floodplains and the environment need to be taken into account. If you want to give 100 per cent protection to the floodplain and grazing interests, then only allow trading downstream! But remember that, the further water is traded downstream, the greater are the losses.
Shepherding water downstream
Imagine what would need to happen if a Queensland entitlement was purchased with the view to increasing river flow in South Australia. To effectively shepherd any water to South Australia, every announcement threshold and every monitoring point along the way would need to be changed, but changed only for each shepherding circumstance. Possible, but development of such a system would require a considerable degree of co-ordination and communication among river managers and jurisdictions. Some refinement of interstate water sharing agreements may be necessary.
Without a shepherding arrangement that allows announcement threshold variation, a decision to increase river flow in downstream states by purchasing a Queensland entitlement to may be a questionable investment. CSIRO estimates that when there is a maximum flow at the St. George weir in Queensland’s Condamine Balonne System, one megalitre of water will deliver only 0.18 megalitres to the Murray Mouth.
Dealing with adverse climate shifts
The last question to consider is the effect of adverse climate shift on the health of an unregulated river system. If there is an adverse shift to a drier climatic regime, then one would expect a reduction in the total flow and in the number of high flow events. In most unregulated systems, however, entitlement holders get access to a larger proportion of the volume of low flow events and to a smaller proportion of high flow events, with most of the environmental water coming from high flow events.
If it gets drier, however, under current entitlement conditions the amount that may be taken during low flow events will remain the same. This means that the environment may lose out. If one was concerned about this happening, then a possible solution would be to define flow-rate thresholds as a function of a long-run moving average (adjusted for any lag effect) so that the impact of the emergence of a shift to a drier regime on the health of an unregulated system is minimised. Note also that if there is a shift to drier climatic regime, all downstream users will get fewer opportunities to harvest water.
Where to from here?
As we write this Droplet, the Murray Darling Basin Authority is starting work on a new Plan for the Basin that will need to address these issues. Amongst other things, this will require the development of ways to raise and lower announcement thresholds on an event by event basis. If this were done, then river managers would be able to shepherd water through several reaches. They should also be able to manage the effects of adverse climatic shifts on downstream users and the environment.
If the intent is to find ways to shepherd water over long distances, and if required, to move it through different jurisdictions, then considerable refinement of existing interstate water sharing agreements may be necessary.
Mike Young, The University of Adelaide, Email: Mike.Young@adelaide.edu.au
Jim McColl, CSIRO Land and Water, Email: Jim.McColl@csiro.au
