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close this book A training manual in conducting a workshop in the design, construction, operation, maintenance and repair of hydrams
close this folder Session 17: Site development (2 hours)
View the document Handout 17A: Settling area - take-off system
View the document Handout 17B: Hydram box
View the document Handout 17C: Guidelines/checklist
View the document Handout 17D: Site development
View the document Handout 17E: Glossary of terms

Session 17: Site development (2 hours)

Time: 2 Hours

Objective: At the end of this session, participants will be able to:

· describe various construction techniques for the major components of a hydram system, i.e., take off from the source, hydram box, storage facility and necessary piping, and

· develop cost estimates for total systems.

Overview: During this session, participants will describe present construction techniques at their sites and compare them. If participants have little/no experience in water development, simple techniques will be described. This session is not intended to provide construction skills for ram components.

Materials: Handouts Costs lists developed prior to workshop, especially PVC and galvanized pipe, concrete Approximate costs developed during construction of hydrams in workshop. Chalkboard, chalk or flipcharts and markers

Procedures:

NOTES

1. Introduce the session with a brief statement that so far the workshop focus has primarily been the hydram itself and that we now want to look at a bigger picture, i.e., the system. State the objectives of the session and review Handout 2B.

10 min.

2. Take off from source. Ask participants to describe methods they're familiar with for taking water off a stream and/or catching springs. Generate a list of design issues and write these on board/flip chart. If participants are not familiar with systems, trainer should describe settling basin, spring catchment, and group should identify in-country resources for developing water sources.

 

3. Ask participants how to protect hydram itself: keeping drive pipe rigid, free of bends, providing adequate drainage, avoiding damage by animals, vandals, or to curious people/children. Develop guidelines for construction of hydram box, per Handout.

10 min.

4. Storage Facility. Repeat Step 2 for storage facilities.

10 min.

5. Have participants size a ram for their application, and cost out the entire system, using the workshop estimates, their knowledge of skilled labor rates. If participants do not have a specific application in mind, develop a sample problem, using information generated in workshop to date, i.e.,

45 min.

cost of rams built

 

maximum h:H for these rams

 

approximate 1 and L

 

provide hypothetical q

 

Check computations to ensure that all components accounted for.

 

6. Ask participants what, if any, additional issues are raised by these site development considerations in terms of costs to community, current systems that hydram could run off of, existing storage systems, costs for reticulation.

 

7. Summarize by stating that all of these must be considered in overall hydram system. Distribute Handouts 17 C, D, and E.

 

 

Handout 17A: Settling area - take-off system


Settling area - take-off system

Handout 17B: Hydram box

Attachment 17-B


Hydram box

Handout 17C: Guidelines/checklist

Take off from source:

materials:

pipe or proper soil drum or tank plumbing parts (connectors, flanges, etc.) trash rack fine mesh screen

concerns:

negative slope from source to drum or pond pipe or channel well into stream good foundation for durm or pond means to shut off flow to basin when necessary keeping trash, debris, sediment out of line protection from: raging waters flood animals sun (ultra violet rays) erosion

Hydram:

materials:

cement, aggregate, sand metal pipe and plumbing parts hydram metal or wood for cover to box hinges, screws, etc. stakes, wire

concerns:

support for pipes - drive, delivery pipe course straight as possible - no 90° bends anchoring of pipes drainage for waste water drive pipe entering settling basin 1/3 way up from bottom of basin protection box for hydram drainage for waste water coverage for all plastic pipes clear marking of pipeline if buried

Storage Facility:

materials:

adequate soil cement, aggregate, sand reinforcing bar paint pipe plumbing parts (connectors, faucet, standpipe) fencing material

concerns:

best match of size, materials and costs closeness to final usage durability of tank - strength, seal protection from animals safety for users, children

Handout 17D: Site development

After the siting of the components for the hydram system has been completed, it becomes necessary to design the components in detail. This session will discuss how to develop them and will allow for a better estimation of the money, labor and time needed.

The components of the system that are of concern here are the takeoff from the source, the hydram, the storage facility, and all necessary piping. Variations for developing the components and factors that influence their design will be presented. The attachments to this session will give further guide lines and will give references for those topics that will not be covered in this manual/workshop.

TAKE-OFF FROM THE SOURCE

As was mentioned before, the water for a hydram system is not taken directly from the stream; a take-off component must be installed. Its purposes are to protect the system from the potential damage by floods, to keep sand and debris out of the system and to make maintenance of the system easier. The two basic parts to the takeoff area are a settling basin and a transmission channel from the stream to the basin.

The size of the basin has to be just large enough to insure an uninterrupted flow of water to the hydram while trapping sediment, sand, and debris. If the hydram system is small - that is, it uses a 2" drive pipe or smaller, a 55 gallon drum or small tank may be used. If the soil at this site has a good clay content, a small pond can be constructed to serve as the basin. A rough way to determine the size of the basin is to determine the volume of water contained in the drive pipe at any point in time and have the basin be large enough to allow 34 times that volume of water standing above the drive pipe, e.g., if the drive pipe contains 10 gallons (area of the inside diameter of the drive pipe times its length), then a basin with 30-40 gallons above the drive pipe inlet will be sufficient. The inlet of the drive pipe should be positioned at least 1/3 of the way up from the bottom of the basin. A fine mesh screen must cover the inlet of the drive pipe (keeps frogs, etc. out).

The second part to the take-off is the channel or pipe that takes the water from the source and directs it to the basin. If a drum or tank is used as a basin, a pipe is more suitable as the inlet channel in that the pipe lends itself to an easier attachment to the drum/tank. If a pond is used, a dug channel can be used. The channel however, may need to be lined with clay to minimize seepage loses through the soil. The channel or pipe should be placed well into the stream to be able to pick up sufficient water during the dry season. The pipe needs to be anchored to the streambed for protection from being swept away by raging waters during the rainy season. A channel also will need to be protected. In both cases, large rocks placed on each side of the channel/pipe should be sufficient.

The channel will need more regular maintenance than a pipe to keep the sediment and weeds from blocking the passage. The pipe will need a trash rack in front of it's stream opening to keep debris, fish, etc. out of it.

The channel/pipe will need to have a slight negative slope to it 1% or so to allow the water to naturally feed into the basin. Both the channel and the pipe should have some means of blocking the flow of water to the system when that becomes necessary. If a plastic pipe is used, it will have to be covered to protect it from the sun; the ultraviolet rays of the sun will eventually destroy the plastic.

One last note: if the stream under consideration has excellent year round flow rates, but not an adequate head to run the hydram, a small dam may need to be constructed. This is a costly undertaking in terms of money, time, skill and labor. This manual/workshop cannot provide the necessary information for working with a dam. You will need more information to help decide if further consideration of the project is worthwhile.

The Hydram

The hydram component consists of the drive pipe, the hydram itself, the delivery pipe and a protection box/foundation for the hydram. Details about development and construction of the hydram are covered in this manual.

The drive pipe needs to be made of metal to withstand the pressures and pounding that develops in running the system. It should be positioned in the settling basin about 1/3 the way up from the bottom. The pipe should be well supported along its length and protected from outside disturbances. If stakes can be driven into the ground, the pipe can be anchored to them; this will help minimize vibrations and keep it from being bumped off its supports. The pipe should transverse as straight a course as possible. In no case should sharp bends (90°) be used; 45° bends or less should be used. If they are used, support must be provided at each bend to keep the side-way thrusts that will develop inside the pipe at that point from destroying the line.

The delivery pipe can be made of plastic. The same care in supporting, anchoring and protecting the drive pipe should be applied also to the delivery pipe. The course of the pipe should be as straight as possible, avoiding all sharp bends. An additional concern with plastic pipe is protection from the ultraviolet rays of the sun. The pipe needs to be covered. One way to do this is to bury it. However, if this is done, the channel should not be covered up until the system is working and the pipe checked for leaks.

The delivery pipe, because of its length, may raise additional concerns. It must be adequately protected any place it has to cross a trail or road, or in other ways is subject to possibly being run over by a cart or vehicle. If it crosses cultivated land, it's course must be adequately marked so that it is not accidentally damaged during cultivation operations.

The hydram itself must be well supported and protected from accidental disturbances. In addition the waste water needs to be directed away from the support foundation. The best way to provide this protection is to build a concrete foundation with drain outlet and a concrete or cement block box around it. The box should be large enough to allow enough room for a workman (or two) to comfortably move around the hydram. If a concrete hydram is used, the accumulator and/or the body may weigh a couple of hundred pounds. If it has to be removed for some reason, there must be enough room in the box to allow workers to get in there and lift it out.

The final part to the box should be some type of cover that can be locked; this offers protection from vandals or people tampering with the hydram out of curiosity. A final note on the construction of the box: the foundation should be poured and the hydram installed. After the hydram is working like it should, the walls to the box should be constructed and the cover installed.

The Storage Facility

The construction design of this component of the system is dictated by its size, the available materials, and physical characteristics of the site. A few examples may highlight some design considerations for the storage facility:

Let's say your calculations for the system indicate that 1000 gallons of water a day needs to be delivered. To store this amount of water, the facility will need to be about 12 feet on a side and 12 foot high. (1 cubic foot of water equals 7.48 gallons) If you want to have a 3-day supply of water (1 day's use and 2 days in reserve) the facility will need to he at least 12' x 12' x 3'. It may be economically reasonable to construct this out of concrete and block.

Now let's say the system will be used for irrigation and will need to store 100,000 gals and use it every 8 days. The size of this facility will need to be approximately 40 feet on a side and 3 feet high. To construct this structure out of concrete may be too costly; a pond would have to be constructed. (Incidentally, a system needing 2100,000 gallons every 8 days will need to pump about 10 gals a minute, all day, every day. 100,000/8 days/24 hours/60 minutes.)

This manual/workshop can not go into all the details and procedures necessary to construct these storage facilities. However, some reference materials are listed in the attachments that can assist in this work. In addition, assistance can be obtained from the agriculture department and technical donor groups/agencies.

Irrespective of the design of the facility, there are basic concerns for the protection of the system and for safety to the individuals using it. A pond almost assuredly will have to have a fence around it to keep animals and little children out of it. The walls of a tank will have to be reinforced with metal bars and the inside of the tank plastered with cement and painted to prevent leaks.

Cost and Labor Considerations

The labor for and the costs of this system can be quite a burden for the rural farmer or village; this is why the siting and the design of the system are so important. When both are done with care and skill, the costs for a completed system will be as low as possible. It should be obvious that with ample free/cheap labor and proper soil available the system can be kept within reasonable limits. It should also be obvious that the amount of labor needed and the length of time to do it all can be extensive.

It may be useful to take an example and see what a system might cost. Prices for everything are different everywhere, hut for the sake of this example, let's say:

• Cement costs $7/bag - 1 bag can make 20 blocks 16" x 8" x 8"; can plaster 50 sq. ft. of surface can bond 35 blocks together; can produce 6 cu. ft. of concrete

• Reinforcing bars for the total system costs $75

• Metal pipe costs $8/foot

• Additional plumbing parts $75.

• hydram can be built for $100

• Plastic pipe costs $4/foot

• 55 gal drum costs $10

• welding work on drum costs $15 e Pipe lengths are: inlet line to drum 20' Drive pipe 40', delivery pipe 200', supply pipe 300' e Hydram box needs to be 6' x 5' and 4 courses high foundation ½ foot thick

• Storage facility needs to be 15' x 15' x 4' foundation - 1 foot thick

• Paint $50

• standpipe and faucet at final use point $100

• Transportation costs $200

• no labor costs

What will this system cost? (round off fractions to next highest whole number.)

If the storage facility will be a pond with no material costs, what will the system cost? (Transportation costs are cut in half; no reinforcing bar is needed.)

If, in addition, the supply line isn't needed, what will the system cost?

Handout 17E: Glossary of terms

Battery of hydrams - (or parallel hydrams) a hydram installation where two or more hydrams are connected to the same source with different drive pipes, but usually with the same delivery pipe. This type of installation is used where the size of the hydram is limited.

Holding tank - (storage tank) the means of storing water once it has been pumped to the desired head.

Ram box - the small structure usually made out of concrete and/or wood which houses a hydram, protecting it from freezing, weathering, and possibly from vandalizing.

Series hydram - a hydram installation where two or more hydrams are used in series to pump water higher than one hydram could alone.

Spring box overflow pipe - a pipe placed in the wall of a spring box near the top for unused water to exit through.

Waste water drain - the drain in the bottom of a ram box which allows the waste water from the hydram to drain out.

Waste water series hydrams - a hydram installation where one hydram uses the waste water from another as a source to pump a higher percentage of the water.