Dredging World News Blog

Lagoon Maintenance Dredging every Decade

Posted by Laura Fleming on Thu, Mar 21, 2013 @ 11:03 AM

SRS Crisafulli has discovered the Rural Water Association.  This winter, Troy Fercho, Frank Robinson, Tristan Hoff and I attended shows in North Dakota, Montana, Minnesota, and Idaho.   At these Rural Water Association Trade Shows, we promoted SRS Crisafulli's dredge equipment and rental services to assist communities in managing the long term, low cost resource of their wastewater lagoon systems. 

Flump Dredge System

When lagoon operators use proven, successful, operating and maintenance procedures, Wastewater Lagoon Plants can get in compliance, and can stay in compliance.  Many lagoons have been in service for 30, 40, or 50 years.  Lagoons should be desludged every 8 to 10 years for optimum performance.

One of our dredge systems, the remote controlled Flump Dredge System, pictured here, is an electric, unmanned system that is available for sale or can be rented directly by a facility or by a contractor.  All of our dredge systems are made in the USA – in Montana to be exact. We provide installation and operator training for dredge sales anywhere in the world, and for rentals anywhere in the USA and Canada.

What have we learned at the Rural Water Shows?  One of the high notes of the Great Falls conference was meeting Steve Harris, an independent consultant from Arizona, who has provided lagoon optimization and troubleshooting services for over a decade.  Steve gave several presentations on lagoon troubleshooting at the Montana Rural Water Association convention in Great Falls.  

How to Upset a Wastewater Treatment Plant

Steve Harris put a little bug in my ear about the impact of methamphetamine laboratories on wastewater treatment lagoons.  Quick investigation produced a similar article in the December, 2012 issue of Treatment Plant Operator, by wastewater treatment plant Laboratory Detective, Ron Tygar, entitled, "Knowing What’s Coming." Ron writes:  “Industries are not the only sources of discharges that can upset treatment plants.  Residential abusers can have big impacts, too.”  In his article, Ron, gave two specific examples of residential sewage abusers - deep fat turkey fryers, and methamphetamine labs.

In the first case, residents sometimes face the dilemma of what to do with 7 to 8 gallons of used cooking oil once the Thanksgiving holiday has passed. Some ingenious homeowners have discovered that the 3-inch PVC clean-out cap sticking up in the yard is conveniently connected to the local sewer system. 

In the second case, the high levels of waste ammonia discharged into the sewer system along with other hazardous substances create a high-strength, or even toxic waste to the fragile micro-organisms.

Troubleshooting your Lagoon

Steve is the author of Wastewater Lagoon Troubleshooting - An Operators Guide to Solving Problems and Optimizing Wastewater Lagoon Systems.  Steve's textbook charts eight general problems in lagoon management: 

     (1)  low dissolved oxygen,  (2)  toxicity, (3)  odors, (4)  low temperature, (5)  high coliform, (6)  high BOD (biological oxygen demand), (7)  TSS Control (total suspended solids), and my favorite, (8)  “Short Circuiting” which refers to hydraulic inefficiencies that allow wastewater to exit a lagoon over a time shorter than necessary to completely stabilize it. 

In terms of the potential value to lagoon operators of a dredging resource, removing sludge scores a 7 out of 8.  Steve offers at least five strategies for each of the eight major issues on the way to optimum lagoon performance and compliance.

There are many fine points in managing wastewater systems.  Our interest as a supplier of "sludge removal systems" is to support the longevity and efficiency of lagoons as operating systems.

As Steve Harris writes in the preface to his textbook, “The knowledge concerning diagnosing and solving operational problems in wastewater stabilization ponds has been greatly expanded over the last twenty years.  Many papers have been published in scientific journals and several excellent books have been written on the subject of wastewater lagoon systems.  Years of consulting with lagoon operators across the US, Canada, Mexico and Central and South America has shown me that little of this valuable information ever reaches lagoon operators.”

Another resource that addresses that same knowledge gap is the Maine Lagoon Systems website, which has a  mission is to promote clean water resources through the enhanced communication of wastewater lagoon system operators in the state of Maine and beyond. This website provides an online presence in which operators of lagoon systems can network with each other on various issues of wastewater treatment relative to today's demand of a clean water environment.

A technical note from the Maine Lagoon Systems offers the following:

It has been reported that as many as 60 percent of the BOD5 (The amount of dissolved oxygen consumed in five days by bacteria that perform biological degradation of organic matter) violations nationally may have been caused by nitrification in the BOD5 test rather than by improper design or operation (Hall and Foxen 1983). Consequently, millions of dollars may have been spent needlessly on new treatment facilities.

To decide if you too want to meet Steve Harris, a 2009 lecture is available on YouTube.

H&S Environmental is committed to helping you get better performance from the wastewater lagoons you're already using.  Their goal is to provide wastewater lagoon operators with practical, easy to use and cost effective tools to solve their toughest wastewater lagoon challenges.  H&S Environmental is committed to the belief that wastewater lagoons are capable of producing high quality effluents...effluents that will consistently meet tougher new permit limits.  Some of the chief problems with wastewater lagoons are operational, but many lagoon problems are the result of design deficiencies that can be fixed.

To learn more about Lagoon Dredging or
to inquire about dredge rentals or purchasing options...
Contact us Now!

 

 

Steve Harris, H & S Environmental

Maine Lagoon Systems

Rural Water Association

Treatment Plant Operator

Topics: crisafulli, dredge, srs crisafulli, lagoon dredges, dredging system, dredging equipment rentals, lagoon, Treatment Plant Operator, Municipal dredging, biosolids, Montana, water treatment plant, wastewater treatment plant, sludge, maintenance dredging

Natchez Wastewater Treatment Facility Finds Success with New System

Posted by Elizabeth Kaiser on Fri, May 04, 2012 @ 08:05 AM

By Elizabeth Kaiser, SRS Crisafulli Marketing Manager

A popular magazine at the SRS Crisafulli offices is Treatment Plant Operator (TPO), which serves municipal water system operators.

The November 2011 issue of TPO featured the Natchez, Mississippi Wastewater Treatment Facility in their Top Performer - Biosolids section, with an article titled "Sun Dried Success". 

"Natchez is the site of a new “greenhouse” solar biosolids drying system" states TPO.

The American Council of Engineering Companies recently awarded WGK, Inc., the general civil/engineering and surveying firm for this project, their Grand Conceptor's Award for the design of the upgrades to the plant.  Congratulations to WGK!

Natchez has two, 3-acre holding ponds.  Prior to their system upgrade, the disposal process for the sludge from these holding ponds was expensive and time consuming.  Natchez WWTF hauled their biosolids - with solids content of 10% - and disposed of the material using liquid injection at a nearby site. 

Today, the wastewater treatment plant produces a biosolid with at least 75% solids that meets class A standards.  A SRS Crisafulli FLUMP dredge helps the plant accomplish this new standard successfully.

 Natchez FLUMP dredge

 Photo Credit:  TPO magazine, November 2011

Installing a FLUMP dredge eliminated transportation and equipment rentals costs, and reduced environmental risks. The total project impact has reduced operating expenses by at least $200,000/per annum.

Michael Stewart, Natchez Wastewater Treatment Plant Manager, told SRS Crisafulli their goal was "not to make money but to save money."  Michael said they "save money every time they start the FLUMP dredge."

The Natchez Wastewater Treatment system went online a little over a year ago.  Today, their Crisafulli FLUMP dredge is operating 8 hours a day, while in production, and is going strong.  The Crisafulli FLUMP dredge pumps the dredged sludge from the ponds to a 65,000 gallon tank.  The sludge is then pumped to a belt press conveyor system.   The FLUMP dredge fills this 65,000 gallon tank twice a day.

The Natchez Wastewater Treatment Facility intends to resell the sun dried product to farmers. The wastewater treatment facility will not only save money with their new system, but will also make money.

Do watch the November 2011 TPO video of the Natchez system, narrated by Michael Stewart, Plant Manager.  He does an excellent job of explaining the art of this 5 million galls/day rated wastewater treatment facility, serving a population of 30,000.

 

 

Read the TPO "Sun Dried Success" article.

Read Natches Democrat article "Water Works awarded for dealing with your waste".

Watch a Crisafulli FLUMP video.

Read Crisafulli FLUMP case histories and testimonials.

 

Topics: Dredges, crisafulli, dredge, dredging, lagoon dredges, dredging system, dredging and pumps, flump, lagoon, TPO, Treatment Plant Operator, Municipal dredging, biosolids

SRS Crisafulli Explores Dredging and Hydropower

Posted by Elizabeth Kaiser on Wed, Jan 25, 2012 @ 08:01 AM

By Elizabeth Kaiser, SRS Crisafulli Marketing Manager

Energy production and consumption worldwide is influenced by many factors.  Resource availability, economic activity, population growth and environmental regulations, for instance, all affect the types of energy production that may be available to consumers.   One of the cheapest methods of energy production is hydroelectric power.

Last spring’s press release by the U.S. Department of the Interior, Departments of Energy and Interior Announce $26.6 Million in Funding to Develop Advanced Hydropower Technologies, announced  “funding for research and development projects to advance hydropower technology, including pumped storage hydropower.”  Hydropower is a sustainable and clean power generating process.  “These funding opportunities will help unlock innovative approaches to hydropower development that emphasize sustainable, clean power generation while reducing environmental impacts.” 

What is the hydropower process?  In short, falling water is passed through a hydroelectric generator to produce electricity. Another hydropower process involves what is called “pumped-storage”. As explained by the Tennessee Valley Authority, “A pumped-storage plant uses two reservoirs, one located at a much higher elevation than the other.  During periods of low demand for electricity, such as nights and weekends, energy is stored by reversing the turbines and pumping water from the lower to the upper reservoir.”

Watch this YouTube video "Hydroelectic Power - How it Works"

 

How is dredging part of this scenario?  The most serious technical problem for hydroelectric dams is accumulation of silt which reduces the water storage capacity of the dam.   Reduced storage capacity limits both electricity generation and the availability of fresh water for downstream uses.  Periodic maintenance dredging removes silt deposits from the dam reservoir and restores water storage capacity, thereby allowing the hydroelectric dam to function more effectively. Periodic dredging can reduce potential negative impacts on fresh water availability without interrupting energy production.

 

Want to learn more about hydroelectric dam dredging?  Contact us.

Watch or download Crisafulli dredge videos.

Subscribe to this blog’s RSS feed for the soon to be announced Rotomite 6000 C Series Dredge.


Topics: Dredges, crisafulli, dredge, dredging, srs crisafulli, dredging abrasive materials, lagoon dredges, dredging system, dredging and pumps, lagoon, rotomite 6000c, Hydraulic dredging

Dredging and Shoreline Remediation

Posted by Elizabeth Kaiser on Wed, Dec 07, 2011 @ 08:12 AM

By Elizabeth Kaiser, SRS Crisafulli Marketing Manager

Many situations can complicate a shoreline’s integrity.  These can range from flooding, hurricanes and man-made disasters and can even include aquatic harvesting and human recreation.  Making efforts to protect a shoreline from these intrusions helps protect economic and recreational interests.  Shoreline remediation is an investment in the overall economic and natural habitat of a community.

As defined by the Erosion Control Technology Council (ECTC), Sediment Control is A practice that captures soil particles on site that have been detached and moved by wind or water.   While different methods and practices are used when it comes to shoreline remediation and sediment control we will examine a specific method, dredging and shoreline remediation.

Let’s look at the Southwest Mordecai Ecosystem Restoration Project or “SWMER”.  According to the SWMER Project Scope found at mordecaimatters.org, “The SWMER Project focuses primarily on several rapidly eroding areas on the southern rim of Mordecai Island.Southwest Mordecai Ecosystem Restoration Project

SWMER complements Mordecai Land Trust’s wave barrier project with the Army Corps of Engineers which involves the planned installation of a barrier off the western coast of Mordecai north of the SWMER area.

The SWMER project required careful planning on the part of Mr. Jim Dugan, President of Pond Recovery Services of Hainesport New Jersey and contractor for the SWMER project.

Jim Dugan has owned and operated dredges for many years and has used them in conjunction with Geotubes for the purposes of shoreline remediation.  He has contracted his restoration services throughout New Jersey and surrounding waterways including the Chesapeake Bay.  President of the Mordecai Land Trust, Jeffrey Hager, wrote of Jim Dugan, regarding the SWMER project, “He (Jim Dugan) proved to be an extremely competent and conscientious field manager,…”

Jim Dugan describes the SWMER project as a material handling challenge.  “We had to move 900 tons of sand to an island in the bay.”  As described in the Mordecai Matters Newsletter, Winter 2010 issue, SWMER involves the installation of close to 600’ of huge sand-filled fabric tubes called Geotubes, slightly off the south-western edge of Mordecai Island.  “The erosion has been severe here and the hope is to stabilize this fragile part of the Island and encourage the deposition of grasses and other organic materials between the island’s edge and the two long sections of Geotube.

Jim explained that they couldn’t use the sand from the bay so they transported 900 tons of clean sand from a nearby quarry by truck.  But how do you get the sand to the island?  “You have to pump it.”  Jim said there were 2 major challenges involved.

  1. Don’t plug the pipeline with too much sand
  2. Water/tide problem

Jim needed to use the water in the bay to mix with the clean sand in order to pump the sand underneath a navigation channel, across the island, and through floating line to the Geotube feed ports.  Jim needed a flexible solution. Since he was pumping downhill under a 15 foot channel, he couldn't risk shutting down with sand in the line. He used one of his Crisafulli dredges to act as a mobile sand pump to adapt to the wind and tide level fluctuations in the bay. The dredge would be flexible enough that his operator could adjust the articulating cutterhead height, angle and distance to the feed, thus keeping the sand-water mix at an constant rate. This also allowed frequent start-stop operation to flush the line and switch Geotube feed ports, thus filling the Geotubes evenly.

sand spreader

Jim used a hopper with a belt to deliver the sand to a sand spreader.  The sand spreader distributed the sand evenly to match the 8 foot wide dredge cutterhead.  The cutterhead mixed the sand and water allowing for an optimal pump mixture.

dredge sand pump

Using the dredge as a sand pump Jim was able to pump the sandy mixture up to ½ a mile directly into each of the geotube ports spaced 20’ apart.   “(This project) needed a lot of flexibility which the dredge allowed for” Stated Jim.

Read Jim Dugan’s SWMER blog of his progress in the Mordecai Matters Winter 2010 newsletter

Watch video of the shoreline with the installed geotubes at Mordecai Island Geotubes in Action on YouTube.

If you would like to email Jim Dugan, send your email inquiry to jimdugan@comcast.net.

Watch SRS Crisafulli videos.

Topics: Dredges, crisafulli, dredge, dredging, marina dredging, srs crisafulli, dredging abrasive materials, lagoon dredges, dredging system, dredging and pumps

Proactive Dredging: A Little Now or a Lot Later

Posted by Elizabeth Kaiser on Wed, Oct 19, 2011 @ 08:10 AM

By Isaiah Helm, Applications Engineer, SRS Crisafulli

 

If public works departments had a list of fun things to do, dredging sediment out of holding ponds would not be on it.  It’s like cleaning the shower in your bathroom.  Whether you make it a frequent quick job or an occasional laborious task, time and effort must be set aside to maintain a fixture that is as critical as it is uninteresting.  This is the scenario that played out for Georgia’s Cobb County-Marietta Water Authority (CCMWA) during the summer and fall of 2010, as reported in Public Works Magazine

CCMWA had two water treatment plants and a 25 million gallon reservoir in need of upgrade to meet the EPA’s Stage 2 Disinfectant and Disinfection Byproduct Rule of 2006.  During the upgrade, one plant would be running, one shut down.  The reservoir had to be at full capacity to do this.  Unfortunately, it hadn’t been dredged since 1978 and was half full of sludge.  

 proactive dredging resized 600The reservoir was restored to its original 14-foot depth
within six months.  (Photo Credit:  Public Works Magazine)

Timing of all the different upgrade stages coupled with the EPA deadline meant the reservoir had to be cleaned out in six months.  (The dredging had originally been scheduled to take place 2013-2014.) 

In other words, the CCMWA had to make up over 30 years of maintenance in 6 months (that would be one nasty shower!).  The result: increased scale, decreased competition, and ultimately an increased cost.  The amount of dewatering equipment doubled.  Four mobile belt presses and four recessed chamber presses were used.  Fifty trucks made four 45-mile round trips per day.  Bidding on the project was limited to the few large contractors who were even capable of completing the project.  There were five bidders and all five of them listed the same two companies as their subcontractors.  Total cost to dredge the reservoir and perform maintenance on the banks and sluice gates totaled just over $4 million.

The World Dredging Mining & Construction Journal [1] contains a version of the article authored by Steve Gibbs.  It goes on to discuss some observations from the project:

One of the lessons learned by CCMWA is the need for regular dredging of the reservoir.  One benefit of regular dredging is economics – greater capacity in the reservoir reduces the amount of pumping necessary to bring water from the Chattahoochee, thus saving electrical costs.  Also, doing a smaller dredging project every five years or so will eliminate the need to do a massive project such as the one just completed.

A deeper, cleaner reservoir will allow suspended solids to settle out better, which will enhance treatment efficiency.  The reservoir will also have ample capacity while the treatment plants are in their construction phase.

“This (the reservoir dredging project) will decrease the potential for water quality problems or process issues at our treatment plants,” said Ginn (CCMWA process engineer). “It’s a very good proactive preventive maintenance step.”

There you have it.  Proactive dredging of sludge-collecting ponds really does make life easier in the end.  It also increases the options:

  • Put out a request for bids on that smaller dredging project every five years

  • Contract with a dredging company to clean out the pond every five years

  • Rent dredging and dewatering equipment directly and eliminate the middleman

  • Purchase an automated or remote dredging and dewatering system and have it permanently installed for complete self-sufficiency

At least it’s something to think about while you’re cleaning your shower tonight.

 

[1] World Dredging Mining & Construction Journal, “Proper Planning for a Perfect Project” (Volume 46, Nos. 11/12, Page 16)

 

Do you have a proactive dredging project in mind?  Fill out our dredge application form.

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Topics: Dredges, crisafulli, dredge, dredging, srs crisafulli, dredging abrasive materials, lagoon dredges, dredging system, dredging and pumps, dredging equipment rentals, rotomite sd110, lagoon, rotomite 6000c, Hydraulic dredging, rotomite 6000

Ask a FLUMP Expert. Seven ways to Secure your Traverse System

Posted by Elizabeth Kaiser on Thu, Jul 28, 2011 @ 08:07 AM

The propulsion and traverse systems are critically important to the operation of an unmanned, cabled dredge. The FLUMP, SRS Crisafulli's unmanned dredge, propels itself along a traverse cable connected to lateral cables at opposite sides of the lagoon, configured at 90 degrees to the traverse cable.

The FLUMP's drive system is onboard.  SRS Crisafulli's FLUMP Specialist, Senior Applications Engineer Eric Lillberg, explains seven ways to secure the lateral traverse cables to land, on opposite sides of the lagoon.

The standard method is to drive three 48" long stakes into a triangular steel base plate on each of the four corners of the lagoon or pond.  From the four corners, wire rope winches are connected to each lateral cable, each of which is connected in turn to the traverse cable that runs the length of the lagoon.  The corner winches can exert 2,000 lbs. of tension into the cable system. 

Normally, this method provides more than adequate results, depending on the length of the traverse cable.

traverse 1 resized 600

Even at 700 lbs. of tension, however, a base plate can be pulled out of soft ground, which leads us to Method #2, a daisy chain setup with multiple stakes connected by chains or cables.

Method #3:  In more permanent installations the use of concrete bollard posts is an economical solution. 

 Traverse   2

 

Method #4: A motorized trolley system mounted on a steel rail structure. A rail structure with a motorized trolley system is the preferred method for permanent installations.  The rail structure adds cost to the system, but can result in a substantial reduction in ongoing operator cost thereby improving the overall return on investment (ROI) from the dredging system.  Traverse 3 resized 600

 

Method #5:  When the lagoon is surrounded by hard packed or rocky terrain, other methods have been utilized, including large concrete blocks, about 32" x 32" x 64" and weighing approximately 5700 lbs.  Depending on the lay of the land, it may take some jockeying to prevent the blocks from sliding, once tension is applied.

 Traverse 4 resized 600

 

Method #6:  We have drilled holes in existing rock and concrete structures to set anchors. 

Method #7:  A not so common, but equally effective approach is to use two motor vehicles, one on each side of the lagoon.  Skilled drivers move the two vehicles in perfect parallel, enabling the system to work with no adjustment to the traverse system. Traverse 5 resized 600

 

No matter what the method, a taut cable is essential to effective unmanned dredging.

Read more about SRS Crisafulli's Cable Traverse System.

Click here to ask us a question.  Mention Eric's article.

Topics: lagoon dredges, dredging system, flump, agriculture

For $50,000, who wants to be a SRS Crisafulli Millionaire?

Posted by Elizabeth Kaiser on Thu, Jul 14, 2011 @ 13:07 PM

SRS Crisafulli's factory location is intriguing.  SRS Crisafulli is a dredge and pump manufacturer with a factory in land-locked Eastern Montana.  "Glendive, Montana is a unique and very rural community" says SRS Crisafulli President/CFO, Laura M. Fleming. "Glendive is about as far off the beaten track as can be found in modern America. We had two visitors from Israel this week, and sent them home with special stories about Eastern Montana."SRS Crisafulli Factory Employees

"Good People Surrounded by Badlands" is a phrase promoted by the Glendive Chamber of Commerce.  "It was even a $50,000 question on Who Wants to be a Millionaire" adds Ms. Fleming.

"When I present at public speaking events, I use the phrase:  'The River is our Teacher.'  The Yellowstone River and the unique terrain in Eastern Montana created the Company - and vice versa - the people who homesteaded in this area developed unique irrigation methods and technology.  The landscape contributes to the DNA of SRS Crisafulli" says Ms. Fleming.

Photojounalist Lynn Donaldson has visited the Glendive and the SRS Crisafulli factory on several occasions.  "You may visit Lynn's Montana blog at www.placesbetweenspaces.com where you will get a taste of real Montana", says SRS Crisafulli Sales Manager Maureen Lundman.

Yellowstone River at Glendive

The 28 year SRS Crisafulli veteran employee, Ms. Lundman, says "Glendive, our 'City by the Yellowstone', offers unrivalled scenery.  The mighty Yellowstone River bisects the town.  We're always watching the river."

Makoshika State Park

"Glendive is bordered by the rugged and majestic Makoshika State Park. Makoshika (Ma-ko'-shi-ka) is a variant of a Lakota phrase meaning land of bad spirits or badlands."

"Glendive is a warm & welcoming community, and a great place to live--with an excellent school system, a 2-year college, state-of-the-art medical facilities, fantastic hunting, fishing and recreation, as well as a good share of the fine arts available locally."

"SRS Crisafulli employees count themselves as fortunate to live under Montana's Big Sky!" comments Ms. Lundman.  

For additional background about Glendive, please visit:  www.glendivechamber.com

For additional information about Makoshika State Park, please visit:  www.makoshika.org

For a taste of real Montana, please visit Photojournalist Lynn Donaldson's blog:  www.placesbetweenspaces.com

Topics: Dredges, crisafulli, dredge, dredging, marina dredging, srs crisafulli, lagoon dredges, International Exports, Hydraulic dredging