Search for:

Man-made Reservoirs

Man-made reservoirs, sometimes called artificial lakes, are important water sources in many countries around the world. In contrast to natural processes of lake formation, reservoirs are artificial, usually formed by constructing a dam across a river or by diverting a part of the river flow and storing the water in a reservoir. Upon completion of the dam, the river pools behind the dam and fills the artificially created basin (UNEP 2000). Seasonal changes of runoff and precipitation feed the reservoir. There are big differences in the size of man-made reservoirs such as big artificial lakes or small pond-like waterbodies. The stored water can be used for irrigation, drinking water after purification, or to produce energy.


On-stream storage reservoir formed by a dam across a valley and its water cycle

A reservoir is an artificial lake called a man-made reservoir. It can be formed by building a dam across a valley, by excavating the land, or by surrounding a piece of land with dykes and diverting a part of the river flow into the reservoir. The water is stored in the reservoir and can be used for irrigationhydro-power, or as a water source for domestic or industrial use. Man-made reservoirs are also very effective constructions to control unexpected floods (see also stormwater management). A reservoir is fed by precipitation, rainwater runoff, or a constant flow of a river. Water loss can occur due to evaporation (especially in arid regions) and depending on the reservoir bottom due to percolation (small reservoirs are often linked). Sediments from rivers or surface runoff can reduce the storage volume of a man-made reservoir significantly (FAO 1992).

Water stored in a valley usually has a higher level than the valley bottom downstream of the dam. Because of this difference in level, the valley can be irrigated by a gravity system or other distribution systems. Water can be taken from the reservoir via a concrete or steel pipe. This pipe connects the reservoir to an irrigation canal downstream. A valve is usually located on the upstream end of the pipe to control the discharge of water into the canal (FAO 1992). The kinetic energy of reservoirs is often used to produce electricity (see also hydropower small-scale and hydropower large-scale).

Ecological Impacts

Where no such water body previously existed the presence of a reservoir in a drainage basin and the abstraction of significant water amounts for storage upstream significantly impacts the watercourse, the flora and fauna, and the human inhabitants in the drainage basin. These potential impacts should be identified and thoroughly examined prior to reservoir construction, in order to comprehensively assess the total value of the reservoir project. Procedures to identify and properly evaluate potential environmental, social, and economic consequences of reservoir construction involve the so-called ‘Environmental Impact Assessment’ (EIA). Such an assessment is now obligatory by law in many countries for all new dam constructions (UNEP 2000).

Ecological impacts of reservoir dams have been reported from various aspects such as barrier for migratory animals like anadromous fish, eutrophication of reservoirs by plankton blooming, decreasing flow volumes in tailwaters, stabilization of flow regimes by flood peak cut, changes in thermal regimes of river water, river bed degradation and increase in substrate grain size by sediment trapping, etc. (TAKEMON 2006). Furthermore, big dams and the extraction of water (e.g. for spate irrigation) can create riparian conflicts (see water conflicts). Also, read the paragraph “Impact on Environment” in the rivers factsheet.

Comparison of the riverbed landscape between upstream and downstream reaches of the Yasugawa Dam in the Yasu River in central Japan. The dam is as old as 53 years and the distinctive riverbed armouring can be observed. White part of rocks indicates thick accumulation of organic matter originated from the reservoir
Comparison of the riverbed landscape between upstream and downstream reaches of the Yasugawa Dam in the Yasu River in central Japan. The dam is as old as 53 years and the distinctive riverbed armoring can be observed. The white part of rocks indicates a thick accumulation of organic matter originated from the reservoir. Source: TAKEMON (2006) 

Basic Design Principles

Factsheet Block Body

Adapted from UNEP (2000)

Different types of reservoir systems.
Different types of reservoir systems. Source: UNEP (2000) 

Like lakes, reservoirs range in size from pond-like to very large water bodies (e.g. Lake Powell, U.S.A.). The variations in type and shape, however, are much greater than for lakes. The term ‘reservoir’ includes several types of constructed water bodies and/or water storage facilities:

  • Valley reservoirs – created by constructing a barrier (dam) perpendicular to a flowing river.
  • Off-river storage reservoirs – created by constructing an enclosure parallel to a river, and subsequently supplying it with water either by gravity or by pumping from the river.

The latter reservoirs are sometimes called embankment or bounded reservoirs and have controlled inflows and outflows to and from one or more rivers. In addition to single reservoirs, reservoir systems also exist and include cascade reservoirs – consisting of a series of reservoirs constructed along a single river, and inter-basin transfer schemes – designed to move water through a series of reservoirs, tunnels, and/or canals from one drainage basin to another.

Pumping from a Reservoir for Irrigation

Adapted from FAO (1992)

A small reservoir in the hills of Tepoztlán (Morelos, Mexico), which is mainly filled by precipitation catchment. The water is extracted by gravity and is protected by a fence to avoid contamination from animals or unauthorised use. The reservoir is sealed with an impermeable liner
A small reservoir in the hills of Tepoztlán (Morelos, Mexico), which is mainly filled by precipitation catchment. The water is extracted by gravity and is protected by a fence to avoid contamination from animals or unauthorized use. The reservoir is sealed with an impermeable liner. Source: STAUFFER (2009) 

The fields located around the reservoir upstream of a dam or surrounding a natural lake are higher than the reservoir or lake’s water table. Here irrigation is only possible with the help of pumping stationsmanual or motorized pumping.

The water level in the reservoir is usually highest at the end of the rainy season, and lowest at the end of the dry season or the irrigation season. Pumps installed at reservoirs and lakes must be able to handle these fluctuations, which are not only vertical but even more pronounced horizontally because the water recedes back to the lowest parts of the reservoir. A dead branch of a river can also be made to function as a reservoir. The branch is filled with water during the wet season and closed off during the dry season so that …

10 Tips for Buying a Tank

This section is designed to help you make an informed decision and choose the best tank for your needs, ensuring that it continues to do an effective job for many years to come.  It’s also vital to know that a water tank is made of the right material for your family’s health and local conditions.  Ask your agent or manufacturer if your poly tank meets and contact us for more information.

Enduraplas Blogs | Water Storage & Rain Harvesting | Buying a Water Tank

Polyethylene Storage Tanks for Water & Chemicals? They will be able to show you a copy of their certification or the tank will be clearly marked as being licensed to the standard.  

The standard isn’t mandatory, or necessarily applicable depending on your tank material, here are some great questions to ask when buying a tank to ensure you’re getting a quality product:

Where was the tank made?

Some imported tanks are made from material that isn’t suitable, might not have a warranty, or include fittings that are difficult and expensive to replace.

Is the plastic used in the tank certified as safe for drinking (potable) water?

Whether it’s just the lining or the entire tank, properly certified polyethylene is safe for drinking water. Unfortunately, some imported tanks may not be made from a material that has been properly tested.  It is important to note that some councils do not allow tank water to be used for drinking.

Does the manufacturer maintain a product trace system?

Good manufacturers will be able to trace your product to its source materials and will hold records of when and where it was made.  They will also be able to provide details of the tests it underwent before leaving the factory.

Does the tank have a warranty?

Don’t be seduced by lengthy extended warranties. Ten years is a very reasonable warranty period for plastic tanks.  Steel and concrete tanks typically have longer warranty periods, 10-20 for steel and 20-30 for concrete. Carefully read the conditions and installation instructions before you buy so that you know your rights and obligations should you ever need to make a claim.

Has the tank design been tested?

Like any material, plastic has some limitations when it is placed under stress (by filling). It’s important that your tank has been well designed and properly tested to ensure it’s suitability for purpose.  Although steel and concrete are stronger materials, it is still important to make sure the design is suitable.

Is the stated capacity of the tank calculated according to the Standard?

The calculation in the standards ensures that manufacturers can only state the actual amount of water that can be stored in the tank once fittings have been installed.

How should I maintain my tank and installation to ensure my warranty remains valid?

Your manufacturer should provide you with written guidelines to help you maintain the base fittings and installation of your tank so it will last and continue to provide excellent quality water storage.

Has the thickness and colour of the plastic been calculated according to the Standard?

The Standard sets strict guidelines concerning the thickness and colour of the material to prevent light entering the tank as this can lead to algae growth.

Does the plastic contain UV protection specifically for our Australian climate?

Our local climate can be incredibly harsh.  Polyethylene is ideal because it contains UV-stabilizing ingredients.  It’s important to check whether the polyethylene used in the manufacture of your tank has been made in Australia. Polyethylene made in Australia has more than twice the UV protection called for in the Australian Standard so you can be sure it is suitable for the tough Australian conditions.

Is the tank made by a member of the Association of Rotational Moulders?

The Association of Rotational Moulders (ARMA) is a representative body of the majority of leading poly tank manufacturers in Australia and New Zealand. We help our members to maintain their status at the forefront of the industry and to set the leading standards in the water tank marketplace.…

How to Select the Best Fluid Reservoir for your Dispensing Application

Often the fluid reservoir for assembly fluids such as glue, oil, grease, and epoxy is decided by the fluid manufacturer. Many industrial fluids are pre-packaged in syringes, cartridges, bottles, or pails before reaching the factory floor. There are, however, a few recommendations manufacturers can consider when selecting the best possible fluid reservoir for an efficient, productive dispensing process.

Looking at the volume of products you’re manufacturing, the type of fluid you’re using, and types of fluid reservoirs available can help you choose the optimal solution and improve the quality of your dispensing results. Although it’s always best to first talk to an expert fluid application specialist, here are a few recommendations to help along your journey.

Let Your Production Volume Be Your Guide

Production capacity should be a key consideration when deciding what type of fluid reservoir you need. If your manufacturing process requires just one 10cc syringe barrel per station per shift with no issues, there’s no need to look at other solutions. If you find your process requires multiple 10cc syringe barrels per station per shift, it may be time to opt for a larger syringe, cartridge, or even a tank to reduce the downtime it takes to swap out smaller syringe barrels frequently throughout the day.

Keep in mind that dispensing syringes and cartridges may still be the best option regardless of production capacity. It depends on the material being dispensed. Because syringe barrels and cartridges are disposable, they’re easier to handle with minimal clean up or maintenance.

  • Recommendations for Low-Volume ProductionFor low-volume production or very small, precise deposits, you’ll likely need a 3cc to 55cc syringe barrel. For low- to medium-volume production with high-viscosity materials, you’ll more often use a 2.5 oz to 32 oz (75 ml to 960 ml) cartridge. For lower viscosity/self-leveling materials, a tank may be considered.
  • Recommendations for Medium-Volume ProductionFor medium-volume production with lower viscosity/self-leveling materials, a 1-liter (0.26 gal) or 5-liter (1.32 gal) tank would be optimal. For high-viscosity materials, a cartridge may still be the best option.
  • Recommendations for High-Volume ProductionFor high-volume production and/or larger deposit sizes of lower viscosity/self-leveling materials, a tank is the best option. For high-volume production with high-viscosity materials, a ratio pump should be considered.
Cartridges Filled

Bigger Fluid Reservoirs Aren’t Always Better

It may seem like choosing a bottle or pail instead of a dispensing syringe or cartridge would increase production since it may not require replacing as often. However, certain considerations such as cleaning and wasted material should not be overlooked.

If the fluid tank you select doesn’t have a replaceable liner or accept pre-filled bottles or pails, cleaning becomes a problem, especially if the fluid is an adhesive or reactive fluid. The time it takes to clean the tank to prevent material from hardening or contaminating new material could surpass the time it takes to switch out a pre-packaged syringe or cartridge.

Fluid waste is another consideration. Industrial syringe barrels and cartridges are designed to minimize fluid waste. When fitted with perfectly matched pistons, fluid can be dispensed completely with hardly a trace residue left in the reservoir. This is important when your process requires an expensive, specialized assembly fluid.

Useful Tip: When selecting a fluid tank, always opt for a tank with a liner and a large opening that makes it easy to clean. Or opt for a tank that accepts pre-filled bottles or pails to make replacing the fluid fast and easy with no cleaning required.

Tanks are Great, but Only with Pourable Fluids

Fluid viscosity is another key consideration when selecting the optimal fluid reservoir for your dispensing application. Whereas fluid cartridges and syringe barrels can handle any fluid viscosity, fluid tanks only accept pourable or self-leveling fluids, otherwise known as low- to medium-viscosity fluids. This can impact your process when, for example, you have a high-volume production capacity and a high-viscosity fluid.

When this is the case, a ratio pump is often the best solution since it accepts pre-filled 5- and 55-gallon drums and provides up to 2500 psi (172 bar) of pressure to promote superior flow of thick fluids to the dispensing equipment.

If you have a low- to medium-volume production capacity and a high-viscosity fluid, a dispensing syringe or cartridge is best because the piston helps dispense the material evenly for accurate, repeatable results.

If you put a thick material such as petroleum jelly into a fluid tank, the tank’s pressure may introduce air tunneling into the material since the air cannot be applied evenly onto an uneven surface. This would result in inconsistent material deposits, which could create unnecessary rework and rejects.

Dispensing Method and Fluid Type Also Matter

Sometimes the method of application influences the type of reservoir you should use. For example, if the application requires a manual dispensing method, it’s often easier and more ergonomic for the operator to hold a syringe barrel as opposed to a dispense valve with air and fluid tubing connected.

On the other hand, if you have an automated cyanoacrylate or fast-curing glue application, you would likely opt for a tank as opposed to switching out multiple syringe barrels per shift. But if you had an automated silver-filled epoxy application, you may not have a choice. You may have to switch out multiple syringes barrels because of the nature of the fluid itself. Fluid reservoir selection often depends on a combination of factors, including the dispensing method, the type of fluid, and requirements of the application.

Fluid Reservoir Troubleshooting

One common pitfall when selecting a fluid reservoir is choosing a fluid reservoir without a precision pressure regulator. This often leads to inconsistent dispensing results because when you set a non-precision pressure regulator at 40 psi, it will fluctuate from 35 psi to 45 psi throughout the course of a day.

Nordson EFD fluid tanks feature precision fluid pressure regulators, which essentially means if you set one at 40 psi, it will maintain constant pressure for a much more precise, repeatable dispensing result. This creates the …

Spotlight on Public Access Greeter Program: Waterbury Reservoir

Visitors to Waterbury Reservoir may have encountered something new at the lake this year: a nice young man wearing a yellow “Public Access Greeter” shirt. This summer was the inaugural year for a Public Access Greeter Program at Waterbury Reservoir, which was established by Friends of Waterbury Reservoir (FWR) with assistance from the Vermont Department of Environmental Conservation’s aquatic nuisance control grant-in-aid program. A part-time greeter, along with a motivated group of volunteers from FWR, offered invasive species education and boat inspections at multiple launch sites around this aquatic gem in central Vermont.

The 860-acre reservoir receives over 60,000 combined visitors to the state parks on the shores of the lake, as well as three public access sites. This year, the greeter and volunteers focused their efforts on the heavily used Blush Hill boat access area. They kept a keen eye out for watercraft and trailers that might be bearing Eurasian watermilfoil, which is not present in the reservoir. Another goal was to contain the spread of brittle naiad, an easily spread invasive plant currently found in portions of the reservoir but rare in other Vermont waterbodies.

During the course of the summer, the greeter and FWR volunteers had over 400 individual interactions with boaters. In three instances, boats were intercepted before leaving the reservoir with live plants attached, and in two of those instances, the species in question were invasive. Luckily, no plant material was found on boats or trailers launching into the reservoir, but there were four occasions when excessive water was drained from boats coming from other lakes. Small-bodied invasive organisms, such as spiny water fleas and juvenile zebra mussels, can be transported in very small amounts of water, so ensuring boats enter the lake drained of water is a primary concern of any public access greeter program.

According to FWR, the inaugural year of the program was highly successful. Zach Johnston, the part-time greeter, did a great job engaging people in conversations and answering questions about the program. FWR noted that they were happily surprised by how interested and appreciative folks were that a greeter was present at the reservoir and that many had further questions about invasive species in general and were interested in the printed material handed out.

Some encouraging words from Chuck Kletecka and Laurie Smith, who administered the program for FWR:

“Overall, the program went really well for our first year. Although we did not have many interceptions, we were able to educate many people and introduce them to the dangers of invasive species introductions. One common thread between all the people we interacted with was the love of Waterbury Reservoir. We hope this summer was just the start of future efforts by the State and FWR to share the ‘love’ and keep our beloved reservoir the beautiful resource it is for years to come.”

Better amenities on the way for public at Waterbury Reservoir

Vermont Business Magazine Eight months of work is underway to improve public access areas at the Waterbury Reservoir. The project will require temporary closures at some sites while work is underway, and will include improvements to parking lots, erosion prevention, and boat ramp upgrades. The locations include Waterbury Dam Boat Launch, Blush Hill Boat Launch and the Moscow Paddler Access. Green Mountain Power (GMP) will be doing the work as part of the company’s commitment to improving the Waterbury Dam and surrounding areas. GMP recently received a renewed license from the Federal Energy Regulation Commission to operate a hydropower generation facility at the Waterbury Dam.

The Department of Forests, Parks, and Recreation says the popularity of the Waterbury Reservoir is growing. “The improvements that Green Mountain Power will make over the next 8 months could not come at a better time,” said Susan Bulmer, Northeast State Parks Regional Manager.

 “We know what a valuable community resource this waterway is and we’re glad to work with the state to make these important upgrades,” said Jason Lisai, Green Mountain Power’s Director of Generation Operations.

As part of the Green Mountain Power improvements, a parking area, river access, and anglers’ trail were recently installed along Little River Road just downstream of Waterbury Dam. The trail was constructed as a collaborative effort with the Vermont state trail crew and GMP. This river access is currently open to the public for use.

All three locations will be finished for the 2019 summer season. Long-term maintenance and management will be performed by the Department of Forests, Parks, and Recreation.

Waterbury Reservoir is the ninth largest waterbody in Vermont, created in the 1930s by the Civilian Conservation Corps as a flood control project. There are two State Parks and 30 remote campsites located on its shores and many people access the reservoir for boating, wildlife viewing, swimming, camping, and fishing each year. Waterbury Reservoir is surrounded almost completely by state land, managed primarily by the Department of Forests, Parks, and Recreation as part of the 44,444-acre Mount Mansfield State Forest.

Scheduled Closures:

Waterbury Dam Boat Launch

Closed: October 14 – November 8, 2018 and February 8 – February 18, 2019

Site improvements will include:

  • Installation of a new composting toilet
  • Installation of a concrete boat launch
  • Paving of the access road and parking area (may occur in Spring 2019 depending on weather conditions)
  • Erosion control and site drainage improvements
  • Traffic flow improvements

Blush Hill Boat Launch

Closed: November 9 – November 27, 2018 and February 19 – February 27, 2019

Site improvements will include:

  • Installation of a concrete boat launch
  • Re-grading the parking area
  • Guard rail installation
  • Erosion control and site drainage improvements

Moscow Paddler Access

Closed: November 28 – December 6, 2018

Site improvements will include:

  • Installation of a concrete hand carry access ramp
  • Re-grading the parking area
  • Erosion control and site drainage improvements

Contact us for more information.…

Waterbury Reservoir’s future could be at risk

The Waterbury Reservoir’s many swimming and boating possibilities drew 42,000 people this summer to the state park. Photo by Gordon Miller/Stowe Reporter
The Waterbury Reservoir’s many swimming and boating possibilities drew 42,000 people this summer to the state park. Photo by Gordon Miller/Stowe Reporter

An argument about how to run the flood-control dam that creates the reservoir could lead to a decision to stop filling up the reservoir for summertime use.

And the reservoir gets a ton of summertime use. It is the centerpiece of Waterbury Center State Park, which is wrapping up a record-breaking season. This summer, more than 42,000 visitors have enjoyed swimming, boating, picnicking and hiking through the park, not to mention the naturalist programs that the park enables.

The reservoir’s future revolves around a new license for Green Mountain Power’s hydropower plant at the base of the flood-control dam. The utility has operated the hydro plant since 1953, but its license lapsed nearly two decades ago. Now, the company is seeking a new license from the Federal Energy Regulatory Commission.

In addition, a permit is required from the watershed management division within the state’s Department of Environmental Conservation.

Permit questions like these involve a balancing of hydropower benefits and environmental concerns.

The state agency will look at “everything from the effects on habitats, overall water quality, water temperatures, sediment levels as well as how the water flows and what happens to water downstream,” said Jeff Crocker, a river ecologist with the watershed division.

Those concerns also involve the effects on fish and other wildlife from raising and lowering the reservoir’s level season by season.

Now, the reservoir is drawn down to 562 feet above sea level in the winter, making room for the spring runoff that, except for the Waterbury dam, could cause flooding. The drawdown shrinks the surface area of the reservoir by 40 percent.

Once the runoff ends, the reservoir level is increased to 589 feet above sea level, creating the swimming-boating mecca at the state park.

The watershed division is concerned that the lowering and raising of water levels does not meet current water standards, said Bill Shepeluk, Waterbury’s municipal manager.

If the decision is to keep water levels low, then recreation at the reservoir would come to an end.

Shepeluk suspects state and federal officials have no idea of the furor that the reservoir debate will cause.

This is what the Waterbury Reservoir looked like for seven years after it was drained in 2000 for dam construction work. The 850-acre summer swimming and boating center all but vanished. Photo by Gordon Miller/Stowe Reporter

“This is a big issue to Waterbury residents, and people will be surprised at how passionate everyone feels about these things,” he predicted.

The community will have a chance to weigh in on the situation at a meeting tentatively scheduled for Oct. 7 from 6:30 to 8:30 p.m. at Thatcher Brook Primary School.

Competing interests

The Waterbury dam was finished in 1938 to prevent the kind of flooding that devastated Waterbury and other Vermont communities in 1927.

The dam holds back the water from the Little River, which flows south from Stowe toward the Winooski River. The Little River carries the runoff from the Stowe valley, including massive winter snowmelt from Mount Mansfield and the western side of the Worcester mountain range.

Once the reservoir was created, fish, loons and other flora and fauna made it their home.

Waterbury has already had a seven-year taste of what life would be like without the reservoir. In 2000, the reservoir was drained so construction workers could shore up the dam; the job took seven years and $24 million.

Shepeluk said Green Mountain Power tends to keep the summertime water level as close to 589 feet above sea level as possible, with a 1-foot leeway up or down. It uses that 2-foot range to generate electricity.

“These 2 feet of fluctuations don’t cause tremendous problems, but they can have a significant effect on water quality,” Shepeluk said.

The watershed division would prefer a permit that says the reservoir depth can’t flucuate up and down, Shepeluk said. Ultimately, it would like the water level to remain low, close to the normal wintertime level, he said.

If the water level is low, Green Mountain Power can still produce electricity from the Little River’s flow. But the hydropower would be less reliable. Now, adjusting the reservoir height ensures a steady flow of water through Green Mountain Power’s turbine, but a shrunken reservoir would make the hydropower dependent on the weather — similar to the utility’s other river-run facilities across the state.

Another option is to keep the reservoir even lower, near 550 feet above sea level — a 39-foot reduction in the normal summertime depth.

In this balancing of competing interests, Shepeluk said the hydropower plant, the environment and recreation could all be losers.

“We will be looking at solutions to allow all the stakeholders to get what they want,” he said.

While Crocker wouldn’t comment in detail, he said “there’s a possibility of changes to the recreation proportions of things but the opportunity would still exist. The parks may have to be redesigned.”…

4 Simple Tips For Improving The Health Of Your Irrigation Dam

It’s a simple truth that the better the health of your irrigation dam, the better the quality of the water that you use for irrigation.

Unfortunately, when left to their own devices, irrigation dams are plagued by the same issues as any other type of man-made water body and this isn’t great for your crops.

We’re often asked about what solutions irrigators should put in place to ensure top water quality and whether they can use the same methods for improving the health of their dam as those who aren’t pulling water out every other day. So, to provide some clarity (pun intended), this one’s just for our irrigating friends, read on to discover our four simple tips for improving the health of your irrigation dam:

Install A Dam Aerator.

Aeration - Total Pumps

In regard to dam aeration, irrigation dams can be treated much like any other water body.

The purpose of installing a dam aerator is to boost dissolved oxygen levels within the dam so the efficiency of your dam aeration system will not be impacted by irrigation activities.

Not only with this additional oxygen boost the health of your dam, it can also improve the quality of your soil as well aerated water is the perfect environment for beneficial aerobic bacteria (more on that later).

Make Use Of Dam Liner.

Pond Liner Replacement

Admittedly, this one is a lot easier during the construction stage but if you find yourself in a situation where your dam is empty (or close enough) installing a dam liner can be a big help in improving your irrigation water quality, clarity and irrigation efficiency.

If your dam is one of the ones that’s simply a hole in the ground that collects and holds rainwater, you’ve probably got a lot of nutrient leaching from the soil into your water. This excess nutrient is the perfect food for algae and aquatic weeds, two issues which can easily suffocate your aquatic ecosystem if allowed to get out of hand.

Plus, the addition of a dam liner prevents dirt particles from rising out of the soil into your dam meaning it will be much less likely to turn brown and muddy.

Our top recommendation for dam liner is EPDM rubber but we can also supply other varieties to suit your needs.

Apply Biological Water Treatments.

What Is a Biological Wastewater Treatment System and How Does It Work?

The application of biological water treatments can also greatly improve the health and water quality of your irrigation dam.

Biological water treatments, like the WaterTreats Biostim range, are natural products crafted from beneficial bacteria and the micronutrients that support these bacteria.

Our top recommendation for treating irrigation dams is Biostim Pellets. This is because the pellets work in the sludge layer at the bottom of your dam rather than in the water column which makes them far less likely to be pumped out when it comes time to irrigate.

Did you know that the same aerobic bacteria that live in your dam also live in soil?

This means that as an added benefit, applying biological water treatments to your dam can also help improve the health of your crops by transforming nasties into beneficial nutrients. The more oxygen you have in your dam, the more your beneficial bacteria populations will flourish and dosing your dam with a biological water treatment further supports the health of your existing bacteria while also adding more.

Obviously you don’t want to dose with a treatment that is going to be sucked straight back out when you irrigate so the application of Biostim Pellets will ensure you treat the areas you want or need to while also supporting the pre-existing bacteria living in your water column which will then be carried to your fields and look after your crops.

Plant Out Your Dam Banks.

Planting the banks of any dam is a good idea to assist in filtration but it is a particularly important improvement for irrigation dams. This is because you most likely have pesticides and other chemicals making their way into your water, be it from your own crop fields or your neighbours. This isn’t great for the bacteria living in your dam and can be fatal for any fishy friends you have in high enough quantities.

By planting hardy species around the banks of your dam, you will achieve both mechanical and biological filtration of any runoff that makes its way into your dam. The helps protect your water quality and crops from any adverse effects which may come from contaminated run off.

Planting out your banks also reduces soil and bank erosion which helps defend against water clarity issues.

Bonus Tip: Apply A Pump Defender.

Matala Pump Defenders are traditionally designed for the protection of submersible pumps, but we received word from Dural Irrigation and some of our other irrigation store stockists that they’re flying off shelves for use with foot valve strainers.

This led to a fairly decent rabbit hole of research, but we are now satisfied with what we found and happily recommend Pump Defenders for this purpose.

Pump Defenders are essentially premium quality filter media in a mesh bag which makes them super easy to install and highly beneficial for your irrigation system. Not only will they greatly reduce the chances of your irrigation system clogging, they will also provide a home for beneficial bacteria right near your irrigation intake which (as noted in the biological water treatment section of this post) is great for improving soil quality as well.

By implementing these tips you can easily improve the health of your irrigation dam and, by extension, that of your crops. These tips will work best when all utilised together, however if you only make a few changes, we strongly suggest that you start by installing a dam aerator and beginning a biological water treatment plan. These two options will have the biggest impact on your water quality and are also vital for the health of any fish stocked in your dam.

Our friendly expert team are always happy to help so do not …

Check out the Waterbury Reservoir For Fun This Summer

Let’s face it, 2020 and 2021 have been really strange years. With the COVID-19 crisis dumped in our laps suddenly last March, it seems like life came to a standstill. We were stuck inside, limited, and prevented from going just about anywhere and facing an uncertain road ahead.

As summer arrived, at least we were all able to get out and enjoy a bit of fresh air. The question then became where to go and what to do in the days of “social distancing”. It has also been a very hot and humid summer with very little rain. One place that I had never visited before was the Waterbury State Park reservoir and dam.

It’s a bit off the beaten path, a quarter-mile off VT Route 100, but perhaps that is what’s so great about it. The day I visited, there were only a few people there and plenty of solitude, summer breezes, and the sound of the water cascading over the dam.

Waterbury Reservoir is also a great place to fish and sometimes there can be quite a few people taking advantage of that along with swimming and wading in the water. There is also a picnic area and places to have a small bonfire near the parking area.

The Waterbury Reservoir is the ninth-largest body of water in the state of Vermont. It was created in the 1930s by the Vermont Civilian Conservation Corps as a flood control project to protect towns and villages along the Winooski River Valley.

Types of Reservoirs

The term “reservoir” can refer to a man-made or natural lake, as well as cisterns and subterranean reservoirs. In this section we focus only on man-made reservoirs. 

Man-made reservoirs are made when dams are constructed across rivers, or by enclosing an area that is filled with water. There are two main types of man-made reservoirs: impoundment and off-stream (also called off-river).

Reservoirs can vary in size and be as small as a pond and as big as a large lake. There is so much variability when it comes to reservoirs – they can differ in size, shape and location. For this reason, it can be misleading to make blanket statements about reservoirs without “significant qualification as to their type”. 

Depending on the purpose of a reservoir, operators will fill a completed reservoir with water, let water flow on through the dam and downstream, or leave the reservoir site empty until it is needed (e.g. a dry dam site for flood mitigation).  

WaterPortal Infographic Reservoirs page

Click image to enlarge.

Impoundment Reservoir

An impoundment reservoir is formed when a dam is constructed across a river. Impoundment reservoirs are usually larger than off-river reservoirs and are the most common form of large reservoirs. 

Off-Stream Reservoirs

Off-stream reservoirs are reservoirs that are not on a river course. Rather, off-stream reservoirs are formed by partially or completely enclosed waterproof banks [3]

The embankments around an off-stream reservoir are usually made from concrete or clay. The size of an off-river reservoir will depend on how large of an area is excavated and how high the embankment is built.

Off-stream reservoirs are generally simple in shape and “virtually uniform in depth” [4] compared to impoundment reservoirs, which tend to have shallower shores and varying volumes and shapes.

Environmental Impact Assessment and Stakeholder Engagement

An environmental impact assessment (EIA) must be completed prior to construction beginning on a large or impactful reservoir and dam site. The EIA process is regulated at the federal government level by the Canadian Environmental Assessment Agency. 

The Alberta government also has its own process for completing an EIA. Alberta Environment and Sustainable Resource Development is responsible for the laws that are related to EIAs in Alberta (the Environmental Protection and Enhancement Act and the Water Act). At an inter-governmental level, the Canada-Alberta Agreement on Environmental Assessment Cooperation is an agreement between the federal government and the government of Alberta that streamlines the EIA process and ensures that the EIA meets the requirements set out by both levels of government [5].

An EIA may include, but is not necessarily limited to, an analysis of the following:

  • Whether the safety of navigation is impacted by the proposed structure;
  • The impact of the structure on migratory fish; and
  • The impact of the structure on endangered riparian species or fragile ecosystems.

Depending on the location of the dam and reservoir, stakeholders may need to be consulted before construction can begin. 


The construction of a reservoir and dam involves many steps that are taken carefully to ensure the dam is operational and meets all safety standards and environmental regulations. 

Diverting the River

Before construction can begin, the river must be diverted in order to make the building process easier. Water can be diverted through constructed channels on the surface alongside the river or through underground tunnels through the rock alongside the river. Both of these methods allow the water to travel downstream of the reservoir site and minimize the amount of water travelling to the construction zone.

 A temporary dam called a cofferdam is built above the main site of the permanent dam. The cofferdam is intended to protect the construction site in the event of a flood. 

On wide rivers, a cofferdam may be built on one side of the river to allow water to flow through half of the riverbed. The area behind the cofferdam will be drained and the first half of the main dam will be constructed. This side of the main dam will not be constructed to completion. There will still be some holes in this section of the dam. The cofferdam will then be removed and the water will flow through the holes in the incomplete main dam. 

Another set of cofferdams is built on the other side of the river and the rest of the main dam is fully constructed. In the final step, the original cofferdam will be reconstructed and the portion of the main dam behind the cofferdam is completed. Once the cofferdam is removed for the last time, the dam is complete and water is stored in the reservoir. 

In some cases, rather than constructing an on-stream dam, a dam is built off-stream in a topographical depression suitable for holding water (off-stream reservoir). Once the dam is completed, the river will be diverted to the off-stream storage site [6].

Preparing the Foundation of the Dam

A crucial step in the lifecycle of building a dam is preparing its foundation. This is the first step in construction for an off-stream dam. For an on-stream structure, the dam foundation is prepared after the river has been diverted.

Once the construction site is drained of water, the dam foundation is excavated. All loose soils and sediment are removed, roots and vegetation are grubbed and all water is removed from the site until bedrock is exposed.

If a dam is being built utilizing a valleywall on one or both sides, any blocks of the valley wall that are unstable are removed. Hundreds to thousands of cubic metres of unsuitable rock may have to be removed to reach bedrock with the appropriate strength, stiffness and permeability  characteristics required for construction.  

The bedrock geology will be surveyed for faults and cavities. Any cavities are filled with grout to increase the stability of the bedrock and to prevent water from leaking underneath the dam. Concrete may be used to fill larger openings such as surface cracks, fissures or irregular surfaces. The foundation surface of the dam will be moistened with …

Attendance reflects the reservoir’s allure

Summer lasted well into October this year, and it extended the busy season at the 850-acre Waterbury Reservoir.

Waterbury State Park often reported its parking lot was full on sunny days.

Little River State Park had more than 41,700 visitors — a 10 percent increase in overall use from 2016, boosted by new bike trails and upgraded campsites.

Waterbury State Park had just over 37,800 visitors to its day-use area, down 18 percent from 2016’s record 46,000. In total, nearly 80,000 visitors were logged in at the reservoir’s parks during the summer, not counting people who used access points that aren’t staffed.

The parks have five access points, several unstaffed, so those people and boats aren’t counted toward the total, but “anecdotally yes, we have seen an increase in usage, always dependent on weather,” said Chad Ummel, the reservoir’s “floating ranger.”

Summer was cold and rainy to start, and in June the reservoir had to close briefly when rainfall pushed the water level too high, but unexpected warmth in October boosted the overall numbers, Ummel said. The state parks actually extended their closing date to Oct. 10.

There was also an overflow effect: “When Lake Champlain has algae blooms, for instance, we do note that we receive more usage,” as when North Beach in Burlington had to be closed this summer, Ummel said.

Three years ago, the state government took over management of the remote campsites along the reservoir, and have been tracking the numbers of campers who visit. The sites are available only on a first-come, first-served basis.

“There was an initial transition because people have been camping on the reservoir for 80 years with virtually no regulation, no oversight, and there was a little bit pushback initially,” Ummel said. “But we found that most people have been quite appreciative for the state’s efforts, the composting toilets, just the presence on the water and overseeing has made for a more tranquil and enjoyable experience for most.”

Most campers seem to be Vermonters, Ummel said, but other New Englanders who have heard about the remote campsites often stay overnight.

Booming businesses

“Once it became summer, it became nice,” said Chuck Hughson, co-owner of Waterbury Sports.


The store opened two years ago in Waterbury, and Hughson says added bike paths in Little River State Park and Perry Hill have definitely attracted more people to mountain biking, he said; the numbers show in his bike-rental business.

“More people are going out with their friends and realizing they can do it too,” Hughson said.

There was no break between fishing and hunting season at the Fly Rod Shop in Stowe, manager Parker Wright noted. “Lots of people come in looking for gear saying ‘Hi, I’m going down to the reservoir,’” he said.

The shop was much busier in October than in years prior, probably due to the weather, Wright said.

There were also lots of people getting out on the water in boats, canoes, kayaks, or on stand-up paddleboards.

“Waterbury Reservoir continues to be a tremendous resource for people to go paddling on,” said Steve Brownlee, owner of Umiak Outdoor Outfitters.

“One of the benefits that we have seen is more people renting boats late in the season. We had terrific warm temperatures in the months of September and October. But the other big difference is the new regulations for keeping the water level high is something new in the last two summers,” Brownlee said.

At the end of 2015, the state decided the Waterbury Reservoir should be maintained at its summertime levels year-round, at about 590 feet above sea level.

In the past, the reservoir was drained every fall to between 540 and 560 feet above sea level, making room for spring runoff, then restored before summer. Now, water flow through the dam is managed to more closely match the natural flow of the Little River.

Exhausted after playing all day, visitors headed into town, and businesses in Waterbury continue to see growth.

“The bars and restaurants love the increased traffic from people enjoying the trails and reservoir,” said Alyssa Johnson, Waterbury’s economic development director. “The activities feed off each other well. There’s nothing better than good food and a cold beer after a day outside.”

“The Waterbury Reservoir is unique. It is a true multi-use body of water where nearly everything is allowed from innertubes to seaplanes,” Ummel said. “So it’s a fascinating scope of use where you get to see people on stand-up paddleboards, and jet ski circles around them. It’s an exciting body of water.”