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infiltration gallery

Happy 91st Pop! It’s been 2.5 years since you were last with us, but it’s funny how many things popped (no pun intended) up today that connect to you. Clearly you are still watching what goes on. We had a family summer cottage located 8 miles east of Grayling Michigan. So today I came across an old book entitled the Old AuSable written in 1963 by Hazen Miller, a U of M doctor (you were a U of M aerospace engineer) who wrote about the area back in the day (1870s to 1920s), just before your father purchased property along the AuSable River. It mentions the great grandfather of my dad’s summer playmates, one of whom just died last summer - his obit came up in my email today. Reminded me of many places I went as a kid. Funny it also reminded me of some of the old “names” that are now being lost to time, but created what exists today. It also helped with some perspective on a proposal I have been working on regarding water supplies and quality. The grayling fish disappeared by 1912 as a result of hanged on water quality (warming and silt), human impacts of logging on the fish and the introduction of other species. My proposal looks at impacts of human activity on SE Florida, especially as it relates to sea level rise and the need to capture additional soil storage capacity through infiltration trenches. The water cannot be discharged to tide due to Human-induced nutrient and roadway pollutants of the potential exists to impact fish populations. So we are looking at moving the infiltrated water to water plants in the future. We can treat the water there, cost effectively while solving another problem – diminishing water supplies for urban populations. This would diminish our need to deal with desalination and the disposal of concentrate, another proposal. Funny how sometimes it all comes together….Good times back then and up there. Making progress today. Thanks and keep on watching out for us!!


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….. 

 

 

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Radio Program last week

Hi all.  Here is another radio show I did last week talking about  my company Public Utility Management and Planning Services Inc. and water sustainability. Take a listen. Let me know what you think.  Thanks

Fred


The concept of horizontal wells arises from riverbank filtration concepts.  Riverbank filtration has been practiced for nearly 200 year in Europe, where the concept was to remove debris form polluted waters by drawing through the banks of rivers.  Much of the concepts for groundwater flow are related to the filtration ability of water to move through a porous media.  The concept was to dig trenches along the river and draw water from the trenches as opposed to the polluted rivers.  The concept worked relatively well.  The result is an abundant, dependable supply of high-quality water with a constant temperature, low turbidity, and low levels of undesirable constituents such as viruses and bacteria. Riverbank filtration also provides an additional barrier to reduce precursors that might form disinfection byproducts during treatment.

Now let’s look at this from another perspective, and we’ll pick on southeast Florida as is provides a great case study.  Sea level rise will inundate coastal property, both via coastal flooding and from a rise in groundwater. Since most stormwater drainage depends on gravity flow, drainage capacity will suffer as sea level rises reducing the head differential between interior surface waters and tide. Saltwater intrusion will be exacerbated. Furthermore, reduced soil storage capacity, groundwater flow and stormwater drainage capacity will contribute to increased flooding during heavy rain events in low-lying areas.  In low lying areas, current practices like exfiltration trenches will become impractical, as will dry retention will become wet retention.

Stormwater utilities will be faced with dramatic, currently unanticipated increases in capital expenditures and operating costs, and time will be needed for planning, design, securing permits and compliance. Additional local pumping stations on secondary canals will be needed to supplant the storm drainage system in order to prevent unacceptable ponding. Design capacities of these stations will depend on local rain patterns, drainage basin size and secondary canal system design.  Many will operate continuously, which means ongoing operations will increase substantially. Hundreds of pumping stations may be needed in some communities.

Permits will be a major challenge due to contaminants in the runoff as regulated by MS 4 Stormwater permits, and the inability to treat this water under the current structure. The cost and energy required for stormwater treatment would be a major concern going forward. But what if we sent this continuous flow to water plants as raw water?  All of a sudden we have a solution to two problems – stormwater and raw water supplies.  How often do you see a 2 for 1 solution?


Talk Radio discussion

Hi All.

This is a radio show I did this week.  One of 4 I have scheduled.  It talks about me and my company, outlook, thoughts.  Take a listen.  Let me know what you think!

Fred


Planning is a process utilized by utilities in order to reach a vision of the utility as defined by the customers or the governing board, or to meet certain demands for service projected to be required in the future.  Understanding and managing the utility’s assets provides important information related to the ongoing future direction of the utility system.  However, the only method to develop that future direction is through the planning process.  Planning should be undertaken on a regular basis by all enterprises in an effort to anticipate in to anticipate needs, clarify organizational goals, provide direction for the organization to pursue and to communicate each of these to the public.  With water and wastewater utility systems, it is imperative to have ongoing planning activities, as many necessary improvements and programs take months or years to implement and/or complete.  Without a short and long-term plan to accomplish future needs, the utility will suffer errors in direction, build unnecessary or inadequate infrastructure and pursue programs that later are found to provide the wrong information, level of service or type of treatment.

Planning can provide for a number of long-term benefits – improvements in ISO ratings to lower fire insurance rates, renewal of improvements as monies become available, rate stability and most importantly – a “vision” for the utility.  In creating any plan for a utility system, efforts to understand the operating environment in which the utility operates must be undertaken.  Second, the needs of the utility must be defined – generally from growth projections and analyses of current infrastructure condition from repair records or specific investigations.  By funneling this information into the planning process, the result of the effort should be a set of clear goals and objectives needs to be defined (Figure 8.1).  However, the types of goals and objectives may vary depending on the type of plan developed.  There are 4 types of plans that may result from the planning process.

  • Strategic Plans – action oriented for management level decision-making and direction
  • Integrated Resource Plans – Actions for utility management to tie all parts of the system together
  • Facilities Plans – for SRF loans support
  • Master Plans – to support capital improvement programs

Any utility planning effort should start with a description (and understanding) of the local environment (built and otherwise).  An understanding of the environment from which water is drawn or to be discharged is important.  Both water quality and available quantity, whether surface or ground water, are profoundly affected by demand.  A reduced demand for surface water helps prevent degradation of the quality of the resource in times of low precipitation.  Reduction in the pumping of ground water improves the aquifer’s ability to withstand salt water infiltration, potential surface contamination, upconing of poorer quality water, contamination by septic tank leachate, underground storage tank leakage, and leaching hazardous wastes and other pollutants from the surface.  Over-pumping ground water leads denuding the aquifer or to contamination of large sections of the aquifer.  Planning for is necessary for surface water systems.  Therefore, source water protection must be a part of any water planning efforts, including the appropriate application sites and treatment needs for reuse and residuals.

So let’s toss sea level rise into the mix.  What happens when sea level rise inundates coastal areas with saltwater and increase freshwater heads inland?  How do we fix that problem and should be plan for it.  Clearly master planning should include this threat (as applicable), just as any regulatory issue, water limitation, disposal limit or change in business practices should be considered.  One means to reduce the impact of sea level induced groundwater levels is infiltration galleries that may operate 24/7.  These systems are commonly used to dispose of storm water (french drains or exfiltration trenches) but what happens if the flow is reversed?  Water will flow easily into the system, just as it does for riverbank filtration. The water must be disposed of, with limited options, but let’s toss a crazy idea out there – could it be your new water supply?  Just asking, but such a system would not be unprecedented worldwide, only in the coastal communities of the US.

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