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A utility’s novel attempt to force farmers to curb pollution in rivers failed. Now the utility is on the hook for millions of dollars to protect the region’s drinking water.
— Read on www.governing.com/topics/transportation-infrastructure/gov-des-moines-water-utility-lawsuit-farmers.html


It’s February already!  Where has the year gone?  My apologies for a January without posts.  Things have been busy here and well, blogging got put on the back burner for me with the new semester starting and a new class to design.  But interesting kernels from January:

The World is Trying to Kill You – Dr. Neil deGrasse Tyson

If you have a 20% failure rate, does that make a speculative technology a waste of time?  Conversely if your success is 20% is it successful?   I think no and no.

Have you noticed that February is the month we have been getting the worst winter weather in the Midwest and northeast? Not December or January?  I used to shovel snow all January and wait for the February respite.

Killer whales are now a protected species.  What does that say about the killer whales as SeaWorld?

There is a honeybee crisis.  No really, a real one.  Not the Jerry Seinfeld movie.  But the lesson is the same.  No bees, no food.  We need to figure out how we are killing them.  No doubt when we find out it will come back on pesticides, herbicides, monocultures, some combination of the above.  Not a good thing for farming.

The bison are under attack again in Montana.  Maybe Mother Nature is trying to tell us something – buffalo want to roam to their winter grazing fields.   And no brucelliosis, the issue rancher bring up as to why the bison are bad, has still NEVER been transmitted from bison to cattle.  Bison are way better on the land since there hooves are much large and they do not compact the ground as much.  But they are not as stupid as cattle.  They know they can walk thought a barbed wire fence.  They are bison afterall!

A Utah rancher shot and killed Echo, the female wolf that made it to the Grand Canyon last summer and became a national story.  He thought she was a coyote.  Um, I think wolves are a little bit bigger than coyotes.  We have a man with a gun who can’t tell what he’s shooting.  What could possibly go wrong with that?

Then there is the bear hunt in Florida because people move closer to the woods and cannot figure out how to secure their garbage of close their garage doors.  Bears get killed.  People…..

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Miami Beach installed $40 million dollars in pumps last summer, with an expected $300 million for.  The nearshore nutrient concentrations increased dramatically (a factor of six), which could adversely impact beach quality, fishing and reefs.  Unintended consequences, but an issue was brought up as a potential concern.


In the last blog we discussed 10 planning steps for sea level rises.  When planning 50-100 years other factors can come into play as well.  As a result, to allow flexibility in the analysis due to the range of increases within the different time periods, an approach that uses incremental increases of 1, 2, and 3 feet of SLR is suggested.  Hence infrastructure is built to meet milestones, not arbitrary dates lessening the potential for stranded assets.. The increments can work as threshold values in planning considerations in terms of allowing planners the ability to know ahead of time where the next set of vulnerable areas will be to allow a for proactive response approach that can be matched to the observed future sea levels.

But prior to developing infrastructure plans, the local community needs to define an acceptable level of service (LOS) for the community. A level service would indicate how often it is acceptable for flooding to occur in a community on an annual basis.  1% is 4 days per years and for a place like Miami Beach, this is nearly 2 ft NAVD88, well above the mean high tide.  The failure to establish an acceptable LOS is often the cause of failure or loss of confidence in a plan at a later point in time.  The effects of SLR of the level of service should be used to update the mapping to demonstrate how the level of service changes, so that a long-term LOS can be defined and used for near-term planning.

With the LOS known, the vulnerability assessment is developed using a GIS based map of topography and the groundwater levels associated with wet and dry season water levels.  LiDAR is a useful tool that may be available at very high resolution in coastal areas.  Topographic maps must be “ground-truthed” by tying it to local benchmarks and transportation plans.  USGS groundwater and NOAA tidal data from local monitoring stations to correlate with the groundwater information. Based on the results of these efforts, the GIS-based mapping will provide areas of likely flooding.

GIS map should be updated with layers of information for water mains, sewer mains, canals, catch basins, weirs and stormwater facilities.  Updating with critical infrastructure will provide a view of vulnerability of critical infrastructure that will be funded by the public sector. Ultimately policy makers will need more information to prioritize the needed improvements.  For example, a major goal may be to reduce Economic Vulnerability.  This means identifying where economic activity occurs and potential jobs.  At-risk populations, valuable property (tax base) and emergency response may be drivers, which means data from other sources should be added.

The next step is to analyze vulnerability spatially, by overlaying development priorities with expected climate change on GIS maps to identify hotspots where adaptation activities should be focused. This effort includes identification of the critical data gaps which, when filled, will enable more precise identification of at risk infrastructure and predictions of impacts on physical infrastructure and on communities. The final deliverable will include descriptions of the recommended concepts including schematics, cost estimates, and implementation plan.

So why go through all this.  Let’s go back to the beginning.  It has to do with community confidence in its leaders.  Resident look at whether their property will be protected.  Businesses look at long-term viability when making decisions about relocating enterprises.  The insurance industry, which has traditionally been focused on a one year vision of risk, is beginning to discuss long-term risks and not insuring property rebuild is risk-prone areas.  That will affect how bankers look at lending practices, which likely will decrease property values.  Hence it is in the community’s interests to develop a planning framework to adapt to sea level rise and protect vulnerable infrastructure through a long-term plan.  Plan or….


I read a recent article in Roads and Bridges on the reconstruction of the roadways to Estes Park.  An excellent effort by state officials and private contractors to rebuild over 20 miles of roads that were wiped away in mid-September when unprecedented rainstorms cut Estes Park off from the front range.  I actually had reservations in Estes Park as part of a plan to go hiking at Lawn Lake, among others.  Lawn Lake was one the harder hit areas in the park.  Went to Leadville.  If you have never been, go.  The early money in Colorado came out of Leadville – silver was the money-maker.   I did a 12 mile hike thought the mining district as it snowed – note it is the 2 mile high City.  Great hike in the am – the photos were fantastic as well.  

But the point is that people expect government to solve problems like the roadways in Colorado.  They expect we will solve water, sewer and storm water problems.  We have done a great job of it because people take these services for granted.  What we don’t want is to have a catastrophic failure, natural or otherwise.. ..


I went to Colorado in July, and it was bone dry like I noted in a prior blog.  The trend was expected to continue, but then something happened.  It rained.  A lot. It’s been raining for almost a month.  Last week it was wet out there, really wet, devastatingly wet on the east side of Rocky Mountain National Park (Boulder, Estes Park, Longmont, Lyons). The rain has not really let up so mountain streams are over-running their banks, flooding streets, washing away bridges, damaging property and businesses.  Helicopter evaluation of the damage indicates that miles of roadways are badly damaged. Route 34/36, the primary eastern entrance to Rocky Mountain National Park may have 17 miles (of 20) damage pavement and foundation needing immediate repair.  Estes Park is cut off from the world and there was mud in the streets.  Rocky Mountain National Park is closed to allow access from Grand Lake for emergency vehicles, residents and supplies.  And eastern emergency route from Nederland is also available.  Tourism has halted in the peak of Fall tourist season.

How fortunes have changed, and continue to change.  Three years ago it was the west side of Colorado with 300 inches of snow that flooded downstream communities.  Three months ago was drought. Are these changes part of a larger issue, or a continuation of the status quo?  Hard to know, but certainly both events were far above any prior events experienced in the area.  The local infrastructure was not constructed to meet these conditions, so either the climate is changing, our models are wrong, or both.  We see the same issue playing out regularly around the world when the 100 year or 500 year storm event occurs and wreaks havoc on a community which does not have infrastructure planned for events like this.

 Expect NE Colorado to be a federal disaster area.  Expect billions to be spent on reconstruction of roadways.   But the larger question is whether the new, replacement infrastructure will survive a similar, or larger climate event in the future.  Will our infrastructure planning be short sighted or will it be adjusted accordingly?  The potential for us to protect infrastructure, and property is completely related to our ability to adjust to infrastructure needs and to minimize exposure to weather events.  Keep in mind our economy and way of life is directly related to our infrastructure condition.  But people want to live near rivers and streams, but rarely consider the real risk and consequences. 

How do we address these risks?  FEMA evaluates the probability of flooding to set flood insurance, but FEMA does not prevent construction in flood zones.  Where construction can occur is a state or local issue.  Of course, few local entities want to limit development in any way, so we keep putting people at risk.  Local officials, like those in Florida, keep pushing FEMA officials to reduce flood risks, despite evidence of increasing rainfall intensity that would increase flooding.  Florida is not alone.  No doubt Colorado officials have the same views.  We need to impress upon local officials the risks and encourage them to reduce risks to citizens.  It’s our tax money and insurance premiums they are raising.  But they are rarely held accountable.  Nor are non-elected officials.  Somehow, this needs to change.  We need leaders to stand up and draw the  line in the sand.


A recent Rolling Stone article outlines a potentially dismal future for south Florida.  I was quoted in the article and give the author a bunch of information.  It is hard to write articles that “pop” in the popular press while conveying facts and figures.  But I would suggest that the future is not quite as dismal as the article depicts.  The sea level rise has been ongoing for at least 140 years as indicated by the Key West tidal station, the longest running tidal gauge in the world, but the amount has been 9 inches since 1920.  True it appears that the sea level rise may be accelerating as a result of warming temperatures in the atmosphere that causes the oceans to expend, plus the loss of ice that runs off from glaciers, but 3 feet by 2100 seems the average or maybe the high average.  That is unlikely to inundate all of south Florida, but keeping the water table low will be a challenge.  I suggest that the challenge can be met and accomplish two goals.  In low lying areas the impact of sea level rise is really manifested as increasing groundwater tables.  An increased groundwater table means less soil storage capacity, which means smaller rainstorms will cause flooding.  The increased flooding is already creating a demand by residents for solutions from local public officials.  We have used exfiltration trenches (French drains) for many years, but increasing water tables will mean many of these systems will not function as they may be currently.  But what if we reverse the concept?  Instead of exfiltration, what if we allowed the water to infiltrate the pipe and go to a central wet well, and then pump the water out of the wet well?  I further suggest that the dumping large quantities of groundwater to the ocean or canals may not be permittable as a result of high nutrients, so what if this water is instead pumped to a water plant as a raw water supply?  Wouldn’t that solve two problems at once? Lots of excess fresh water supplies in an era where there are significant limitations in fresh water supplies?  Just thinking….. 

 

 


Based on my last blog, his inquiry came to me.  And I think I actually have an answer:  when bakers and insurance companies decide there is real exposure.  Let’s see why it will take these agencies.  There is very little chance, regardless of good faith efforts, significant expertise, or conscientious bureaucrats to stop growth and development.  The lobby is simply too strong and local officials are looking for ways to raise more revenues.  Development is the easiest way to increase your tax base.  As long as there are no limits placed on develop-ability of properties (and I don’t mean like zoning or concurrency), development will continue.  But let’s see how this plays out.  Say you are in an area that is likely to have the street inundated permanently with water as a result of sea level rise (it could be inland groundwater, not just coastal saltwater).  For a time public works infrastructure can deal with the problem, but ultimately the roadways will not be able to be cleared.  Or say you are located on the coast, and repeated storm events have damaged property.  In both cases the insurance companies will do one of three things:  Refuse to insure the property, insure the property (existing) only for replacement value (i.e. you get the value to replace) but no ability to get replacement insurance, or the premiums will be ridiculous.  We partially have this issue in Florida right now.  Citizen’s is the major insurer.  It’s an insurance pool created by the state to deal with the fact that along the coast, you cannot get commercial insurance.  So Citizens steps in.  The state has limited premiums, and while able to meet its obligations, in a catastrophic storm would be underfunded (of course in theory is should have paid out very little since 2006 since no major hurricanes have hit the state, but that’s another story). 

As the risk increases, Citizens and FEMA, the federal insurer, have a decision to make.  Rebuilding where repeated impacts are likely to happen is a poor use of resources and unlikely to continue.  Beaches and barrier islands will be altered as a result.  The need will be to move people out of these areas, so the option above that will be selected will be to pay to replace (move inland or somewhere else).  Then the banks will sit up.  The banks will see that the value of these properties will not increase.  In fact they will decline almost immediately if the insurance agencies say we pay only to relocate.  That means that if the borrowers refuse to pay, the bank may not be able to get its money out of the deal on a resale.  We have seen the impact on banks from the loss of property values as a result of bad loans.  We are unlikely to see banks engage in similar risks in the future and unlikely to see the federal insurers (Fannie Mae, Freddie Mac) or commercial re-insurers like AIG be willing to underwrite these risks.   So where insurance is restricted, borrowing will be limited and borrowing time reduced.  That will have a drastic impact on development.  The question is what local officials will do about it?

There are options to adapt to sea level rise, and both banking and insurance industries will be paying close attention in future years.  Local agencies will need a sea level rise adaptation plan, including policies restricting development, a plan to adapt to changing sea and ground water levels including pumping systems to create soil storage capacity, moving water and sewer systems, abandoning roadways, and the like, and hardening vulnerable treatment plants.  Few local agencies have these plans in place.  Many local officials along the Gulf states refuse to acknowledge the risk.  What does that say about their prospects?  Those who plan ahead will benefit.  Southeast Florid a is one of those regions that is planning, but it is slow process and we are only in the early stages.


Among the many things I do is work with college seniors as they get ready to graduate and hit the job market.  The changes you use in many of these students over that last year in school is often significant, and in some cases remarkable.  Different students grow differently and the potential starts to appear.  Some gain confidence in their skills and begin to grow into the profession.  Some of these students are likely to make good leaders in the field in the future.  But trying to guess which ones and why it is often a challenge.  However I want them all to have some concept of what leadership is all about.  For many of them, they will end up in the water/wastewater/stormwater field.  They are going to have to deal with tough issues like rebuilding deteriorating infrastructure, sea level rise, climate changes, stressed water supplies, energy demands and a more demanding electorate.  They will recommend increasing water and wastewater fees.  But will they have the skills to encourage decision-makers to move forward with the needs of the system.  You see, that’s where leadership comes into play.  Often it is little things that set things into motion.  Our engineers go into the world with a technical skills et, that ability to learn to solve problems with solutions.  We try to encourage them to be creative.  An assigned reading is “The Cult of the Mouse” by Henry Caroselli, who urges creativity above profits in the workplace.  Mr. Caroselli is right in that it is creativity that allows us to come up with innovative solutions, the ones that change how we live.  It is also where the patents and economic opportunities exist.  America rose to greatness in the 20th century in large part because of automobiles – we figured that out and it made some many things possible.  Computers became common place in the latter part of the century.  We use the technology for both in the water/wastewater/stormwater industry.  In fact they have made us so much more efficient that costs have not climbed as fast as they might have, which is why cable tv is normally more expensive than your water bill.  Which one do you need to live?  My hope is that today’s students figure out energy solutions that will carry us forward as a world leader in the 21st century.  Those alternative energy options, greater efficiency of current technology.  Each will allow the utility industry to improve it’s efficiency further.  The City of Dania Beach built the world’s first LEED Gold water plant.  That took a little vision on the part of the utility director Dominic Orlando.  And a cooperative team of consultants and students.  When we give these projects to young people we can be surprised because they often don’t know that “that’s not the way we do it.”  Well that’s exactly what Mr. Caroselli said.

So we look for leadership.  Creativity, innovation and the “Can-do” mentality are part of leadership, but not all.  There is that ability to set a vision, like Mr. Orlando did in Dania.  There is the ability to convince decision-makers of the wisdom of an idea, as opposed to doing like we always did to make the shareholder happy as Mr. Caroselli noted.   Selling innovation is often the hard part because that’s were the costs are.  But there is more.  Often the selling of a good idea is difficult.  You can be ridicules by the status quo.  Many ideas are just lost in the shuffle because they never receive a voice.

Leadership is often not understood at the time it is occurring.  Ok, maybe we figured this out when Lincoln was President, but if you read accounts of his Presidency, the early years are marked with indecision and backtracking before he got it right.  Most of that is forgotten in lieu of the ultimate results.  Many of the issues we face today need real leadership to create a long-term solution.  The “fiscal cliff” issue is a prime example, as it the long-term need for solutions for social security, Medicare and medical costs in general.  The need to fix the infrastructure that made our economy strong should be among those priorities also.  Remember, we don’t remember the councilman, mayor, legislator. manager, director or President who did not raise taxes or water bills.  They do remember those who solved problems


Storms highlight the need to reduce infiltration and inflow into the collection system so as not to overwhelm the piping system causing plant damage or sewage overflows into streets, so much of the focus has been on dealing with removal of infiltration and inflow through televising the sewer system and sealing or lining sections where leaks are noted.  However, many miles of videotape show virtually nothing, so significant money is spent to find “nothing.”  Part of this is because “infiltration” and “inflow” are not the same, and storm events do not highlight infiltration nearly as much inflow.

The manholes and clean-outs are required for access and removal of material that may build up in the piping system and for changes in direction of the pipe.  Manholes are traditionally pre-cast concrete or brick, with brick being the method of choice until the 1960s.  Brick manholes suffer from the same problems as vitrified clay sewer lines – the grout is not waterproof so the grout can leak significant amounts of groundwater.  The manhole cover may not seal perfectly, becoming another source of infiltration.  Pre-cast concrete manholes resolve part this problem, but concrete is not impervious either.  While elastomeric or bituminous seals are placed between successive manhole rings, the concrete is still exposed.  Many utilities will require the exterior of the manholes to have a coal-tar or epoxy covering the exterior which helps to keep water out.

Inflow results form a direct connection between the sewer system and the surface.  The removal or accidental breaking of a cleanout, unsealed manhole covers, laterals on private property, connected gutters or storm ponds, damaged chimneys from paving roads, or cracking of the pipe may be a significant source of inflow to the system.  All are potential sources of inflow which can be identified easily during storm events.  The peaking that correlates with the rainfall is inflow, not infiltration since infiltration is part of the base flow that creeps upward with time.  When operators see peaks, this is not indicative of infiltration which is groundwater.  Think inflow.   Inflow causes peaks in run time on lift station pumps, and create potential overflows at the plant.  The good news is that simple, low tech methods can be used to detect inflow, which should be the precursor to any infiltration investigation.

The following outlines a basic program for inflow detection and correction for any utility system.  The order is important, and pursuing all steps will resolve the majority of issues.  The first step is inspection of all sanitary sewer manholes for damage, leakage or other problems, which while seeming obvious, usually surprises.  The manhole inspection should include documentation of condition, GPS location, and some form of numbering if not currently available.  Most manholes have limited condition issues, but where the bench or walls are in poor conditions, that should be repaired with an impregnating resin.

Next is repair/sealing of chimneys in all manholes to reduce inflow from the street during flooding events.  The chimney includes the ring, cement extensions, lift rings, brick or cement used to raise the manhole ring.  Manhole covers are often disturbed during paving or as a result of traffic.  The crack between the ring and cover can leak a lot of water.  The intent of the chimney seal is to prevent inflow from the area beneath the rim of the manhole, but above the cone.

The next step is to put dishes into the manholes.  One might think that only manholes in low lying areas get water into them, but surprisingly every manhole dish that is properly installed has water in it.  Hence assume that all manholes leak water between the rim and cover.  Most collection system workers are familiar with dishes at the bottom of the manhole where they are of limited use.  This is because the dish deforms when filled with water or is knocked in when the cover is flipped.  The solution is a deeper dish with reinforcing ribs.  No ribs, don’t use it.  A gasket is required.

Once the manholes are sealed, smoke testing can identify obvious surface connections.  The normal notifications, inspection and documentation will identify broken or missing cleanout caps, surface breaks on public and private property, connection of gutters to the sewer system, and stormwater connections.  All should be documented via photograph, by associated address and public or private location. The public openings at cleanouts can be corrected immediately.  However, if the cleanout is broken, it may indicate mower or vehicle damage, that can occur again.  If missing, the resident may be using the cleanout to drain the yard.  In either case the collection system needs to be protected.  USSI (http://www.elastaseal.com/about_us.html), located in Venice, FL developed a solution, called the LDL plug to correct those commonly broken or commonly opened cleanouts to reduce inflow.

Notices should then be sent to property owners with documentation of the inflow connections to their property.  This is sometimes the most difficult part of the program due to political will, but it is necessary.  This finishes the inflow correction portion of the project, but one more step will help focus efforts for the second “i”.

The final step is a low flow investigation, which is intended to focus on the infiltration piece of the problem.  Such an event will take several days and must be planned to determine priority manhole to start with and sequencing.

Based on a projected plan and route:

  • Open the manholes
  • Inspecting them for flow
  • Determining if flow is significant.  If investigation of basin will end and new basin will be started.  If flow exists, open consecutive manholes upstream to determine where flow is derived from.  Generally a 2 inch wide bead of water is a limit of “significant” infiltration.

Documentation of all problems and corrections in a report to utility that identifies problem, location and recommended repair.  Identification of sewer system leaks, including those on private property (via location of smoke on private property).

The example in Dania Beach, FL was that the last step indicated that only 15% of the sewer system needed to be televised.  This saved the City almost $1.2 million.  Their total costs is under $1.4 million for all parts of the project, spread over several years and contracts.  Overall the hope is that the inflow and infiltration programs together will save $400,000/yr, a five year payback.  But the key is to insure you get the inflow as well as the infiltration… Otherwise storms will continue to overwhelm plants, creating public health concerns and ruining your reuse program.


October is the month that brings us the astronomical tides, or locally to the coasts, the annual high, high tide.  The position of the moon relative the Earth creates a slight alteration in the gravitational pull of the moon on the oceans so high tide, is, well high!  If you lived in a coastal areas, what did you see?  Or experience?  Southeast Florida was rife with email chatter and photographs of flooded streets, yards, and canals.  The City of Fort Lauderdale sent notices to residents warning them about the tides.  We had no rain, just the tide coming in.  These are low lying areas that 20 years ago did not flood except during storms.  This is just a phenomenon that has been monitored in coastal areas over the past 5-10 years, depending on the complaints that have come into local officials.

One of the more interesting complaints I received in my career was in Hollywood Florida where a resident complained about the “fish in the street.”  Sure enough, the storm drain in front of his house was connected directly to the Intracoastal waterway and the October tides had pushed the saltwater up through the catch basin into the street.  Now these weren’t snook or redfish, they were little fish escaping the snook and redfish, about 3-5 inches long.  Pretty funny stuff if you think about it.  Realizing the problem, I called him 3 hours later and asked if the problem had been solved.  He said told me I was a genius to fix that so fast.  My boss told me to take advantage of luck and drop the explanation, but to design a solution (which we did).  My boss was right, but the call made me more cognizant of the issue.

15 years later, I have a student developing models of what happens during the annual high and average tides, especially with respect to the potential for flooding in low lying areas where groundwater is just below the surface.  His work is impressive.  A lot more land, especially inland, may flood as a result of the annual tides, which are a precursor to the long term trend of rising seas.  See the groundwater has a slight upward gradient as you move inland.  As a result, you cannot use the tide levels to predict inland flooding, you need to add the tides on top of historical groundwater levels.  Of course the wet season is the summer in Florida, so the October tides come just at the time groundwater levels are highest.  But at least we can determine where the stormwater pumping improvements need to go.

Determining where stormwater pumping is needed is only part of the problem.  As sea levels rise, more stormwater management will be needed and a place to put the water will become a problem.  Discharging nutrient laden stormwater to tide is not a good answer when you have fragile reefs offshore.  NOAA’s Florida Area Coastal Environment  (FACE) Initiative outline this (see intensives study – http://www.aoml.noaa.gov/themes/CoastalRegional/projects/FACE/Publications.htm).  Instead, perhaps at some point we may develop infiltration systems to capture this high water table “problem” and convert it to water supplies, solving two issues for southeast Florida.  Might be 2030, but we probably should be doing some planning….

 

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