chapter 2 − planning considerations€¦ · montana stockwater pipeline manual chapter 2 −...

Montana Stockwater Pipeline Manual Chapter 2 − Planning Considerations

(210-V-MSPM, Amend. MT2, Feb. 2016) i-1

CHAPTER 2 − PLANNING CONSIDERATIONS TABLE OF CONTENTS

PART 2.1 GENERAL 2-1

PART 2.2 PLANNING PROCEDURE 2-3

2.2.1 Objectives 2-3

2.2.2 Resource Inventory 2-3

2.2.3 System Alternatives 2-3

2.2.4 Landowner decisions 2-4

2.2.5 Implementation 2-4

2.2.6 Follow-up 2-4

PART 2.3 SOURCE OF WATER 2-4

2.3.1 Springs 2-4

2.3.2 Surface Source 2-4

2.3.3 Well 2-4

2.3.4 Water Quality 2-4

PART 2.4 WATER QUANTITY REQUIREMENTS 2-8

PART 2.5 DESIGN FLOW RATE 2-10

PART 2.6 WATER STORAGE AND DRINKING SPACE REQUIREMENTS 2-14

2.6.1 General Discussion of Storage Volume and Drinking Space 2-14

2.6.2 Undependable Water Supply 2-15

2.6.3 Dependable Water Supply 2-15

2.6.4 Conventional Grazing-Low Stock Density 2-16

2.6.5 Conventional Grazing-Moderate Stock Density 2-16

2.6.6 Management Intensive Systems 2-16

2.6.7 Winter Feeding Areas 2-17

2.6.8 Reserve Storage 2-17

2.6.9 Water Access Perimeter 2-18

PART 2.7 EXAMPLES 2-19

Example 1A: Typical Pressure System-unknown stock density 2-19

Example 1B: Typical Pressure system-low stock density 2-20

Example 1C: Typical Pressure system-moderate stock density 2-21

Example 2: Typical Pressure System-long travel distance 2-22

Example 3: Typical Timer System-central storage tank 2-23


(210-V-MSPM, Amend. MT2, Feb. 2016) i-2

Example 4: Solar System-no storage tank 2-24

Example 5: Solar System-central storage tank 2-25

Example 6: Solar System-with other available water 2-26

Example 7a: Management Intensive System-high flow 2-28

Example 7b: Management Intensive System-low flow 2-29

Example 8: Management Intensive System-central storage 2-30

Example 9: Winter Feeding Area 2-31

FIGURES

Figure 2.1 Stockwater Pipeline Planning Procedure Flow Chart 2-2

Figure 2.2 Flow Rate for Daily Needs (Supplied in 4 hours) 2-10 Figure 2.3 Flow Rate for Daily Needs (Supplied in 6 hours) 2-11

Figure 2.4 Flow Rate for Daily Needs (Supplied in 12 hours) 2-12

Figure 2.5 Stockwater Pipeline Resource Inventory Worksheet (MT-ENG-20) 2-13

TABLES

Table 2.1 Use of Saline Water for Livestock 2-6 Table 2.2 Effects of Nitrates on Livestock 2-7

Table 2.3 Minimum Daily Stockwater Requirements 2-8 Table 2.4 Recommended Maximum Travel Distance to Watering Facilities 2-9

Table 2.5 Total Daily Stockwater Requirements 2-14 Table 2.6 Round Stock Tank Storage Capacity and Tank Perimeter 2-15 Table 2.7 Reserve Storage Requirement 2-17


(210-V-MSPM, Amend. MT2, Feb. 2016) 2-1

CHAPTER 2 − PLANNING CONSIDERATIONS

PART 2.1 GENERAL

When planning a stockwater pipeline, it is always important to follow good resource planning procedures. Figure 2.1 illustrates the NRCS planning process as it relates to stockwater pipelines. The planning processes must be followed, even when we are involved with a system where the landowner knows exactly what he/she wants, and we are in a rush to get the job done.

To do otherwise frequently leads to such problems as: • System that does not meet resource conservation needs • System that does not meet the needs of the cooperator • System that cannot later be expanded • An overly expensive system.



Figure 2.1 STOCKWATER PIPELINE PLANNING PROCEDURE



PART 2.2 PLANNING PROCEDURE

2.2.1 Objectives

Find out about the landowner's objectives. Does he/she want a more dependable supply of water, better grazing distribution, better water, or what? We also need to remember why we are involved and what our objectives are. Our objectives are to maintain the resource base, and enhance the environment. We accomplish this by aiding the land user in the development of a Resource Management System (RMS). These objectives should be clearly in mind before we start the next step.

2.2.2 Resource Inventory

Information which must be obtained when planning a stockwater pipeline system includes: • The annual grazing period, including whether or not the pipeline will need to operate in freezing

weather. • The types and maximum number of livestock which will use water at any given time. • Future expansion and management considerations. • The type of grazing system to be used. • The area to be serviced by the pipeline. • Location and details of existing water sources in the area to be serviced by the pipeline. • Reliability and quality of existing water sources in the area to be serviced by the pipeline. • Location, reliability and quality of water source or sources which may be used as a supply for the

pipeline. • Desirable watering locations based on an analysis of range use patterns, range conditions,

geology, and topography. • Geologic considerations including location of shallow bedrock, unstable soils, coarse gravel

subsoils, old slide areas, wetland areas, sharp breaks in slope, etc. • If wetland areas are to be traversed, a determination as to requirements or limitations involved in

crossing the wetland. • Property line and ownership considerations. • Topographic information, including any necessary engineering surveys or study of topographic

maps. The worksheet, MT-ENG-20 “Stockwater Pipeline Resource Inventory Worksheet”, illustrated in Figure 2.5 and in Appendix A, may be used as an aid in obtaining necessary resource information. Blank worksheets are also available on the Montana NRCS website.

2.2.3 System Alternatives

Even though the landowner may have a very specific system in mind, all reasonable alternatives should be considered to assure that the appropriate alternative is selected.

Economic considerations are usually a major factor in determining stockwater system alternatives. It is important to consider upgrading existing water sources; such as ponds, spring developments, and windmills, as alternatives to an extensive stockwater pipeline system, or as a backup to the pipeline system in the event of failure.

The use of average cost data, computer spreadsheets, and specialized computer programs can aid in analyzing various pipeline alternatives. These aids should be used whenever possible to save time and effort.



2.2.4 Landowner Decisions

We sometimes forget to determine the owner’s final decisions before proceeding with detailed pipeline design. Good, appropriately timed communication with the land user is always critical to success of the project. To do otherwise will usually waste everyone's time and money.

2.2.5 Implementation

Implementation of the Resource Management System includes preparation of detailed plans for such practices as fencing, range reseeding, and planned grazing system; as well as design and preparation of pipeline and tank drawings, specifications, quantities, cost estimates, and operation and maintenance plans for the pipeline. It also includes required inspection during application and construction.

2.2.6 Follow-up

Pipelines can be complex and may sometimes experience problems. We must be constantly alert for problems such as waterhammer, freezing pipes, erosion, low flows, and improperly functioning valves so that they can be corrected, and avoided in future jobs. This means that we must maintain contact with the landowner and re-visit some of the pipelines after they have operated for a period of time.

PART 2.3 SOURCE OF WATER

Water for livestock pipelines usually is obtained from wells or springs. Occasionally a surface source is used.

2.3.1 Springs

Springs often have varying degrees of dependability. If it is proposed that an extensive pipeline be run from a spring, the spring should be developed and used for a couple of years to prove its yield and dependability before installing an extensive pipeline.

Sediment, moss, scum, fish, frogs, mice, and other solids must be excluded from spring pipelines to the extent possible. Where the spring collection system allows entry of this type of material, a spring box with screened pipe inlet must be employed. If a gravel/pipe type of collection system is used, a spring box is usually not necessary.

2.3.2 Surface Source

Special care must be used to exclude scum and sediment from pipelines using surface water as a source. A screening or filtering device should always be used at the entrance to the pipeline. If sediment is a problem, consider constructing a settling pond at the entrance to the pipeline.

2.3.3 Well

Some wells produce considerable amounts of sand. A sand separator should be installed at the beginning of the pipeline in such a case. Sand separators are available through trickle irrigation supply sources.

2.3.4 Water Quality

The following is taken from “Water Requirements for Pastured Livestock”- Prairie Farm Rehabilitation Administration – Canada.

Water quality can affect both total water consumption and the general health of the livestock. Elevated water temperatures and objectionable taste and odor will discourage consumption, and reduced water consumption will, in turn, result in a reduction of feed intake, with the net result being decreased weight gain.



The most common water quality considerations that make water unsuitable for livestock consumption are salinity (the concentration of various kinds of dissolved salts), nitrates, algae, and on rare occasions, other factors such as alkalinity or pesticides.

Salinity Dissolved salts can consist of any combination of calcium, magnesium, and sodium chlorides, sulfates and bicarbonates. While all have slightly different effects on animal metabolism, none are particularly worse than any other. Also, the effects of various salts seem to be additive, meaning that a mixture seems to cause the same degree of harm as an equivalent concentration of a single salt. Animals seem to have an ability to adapt to saline water to some extent, but abrupt changes may cause harm. Animals may avoid drinking highly saline water for a number of days, followed by a period of high consumption which causes illness or even death.

Nitrates Water analyses generally report nitrates and nitrites together. Nitrate toxicity resulting exclusively from water is rare, but is primarily of concern when combined with forages having high nitrate levels. Nitrates themselves are not very toxic, but bacteria in ruminant animals (dairy and beef cattle) will convert the nitrates to nitrite which reduces the blood’s ability to metabolize oxygen and effectively causes shortness of breath and eventual suffocation.

Sulfates Water that is high in sulfate salts exists in Montana. Excess sulfate leads to problems in livestock ranging from reduced water intake, digestive problems, polio, and in extreme cases, death. Higher concentrations of sulfates can occur during drought periods or low water conditions. Sulfates are dissolved in water. Total Dissolved Solids (TDS) meters measure any dissolved solid, including salt, or mineral, and the lower the TDS number is, the purer the water. These meters are quick, easy, and inexpensive, and are adequate for most applications. While these meters are relatively accurate, they are an estimate and they do not indicate any particular constituent. It is recommended that a water quality test be taken when TDS levels are above 3000 ppm.

Alkalinity Excessive alkalinity can cause physiological and digestive upset in livestock, but the level at which it becomes troublesome and its precise effects have not been thoroughly studied. Most waters are alkaline in nature, but fortunately, in only a few instances has it been found that a water source has been too alkaline for livestock. Alkalinity is usually expressed as a concentration of Calcium Carbonate (CaCo3), in parts per million (ppm) or milligrams per liter (mg/L).

Bacterial Contamination Most water has varying levels of bacterial contamination, but such contamination does not generally cause problems for livestock. Calves can sometimes suffer from Coccidiosis, which can lead to bloody diarrhea, dehydration, weight loss, depression, and sometimes death. Elevated water sources and a reasonable effort at maintaining cleanliness of watering facilities can reduce the potential for problem causing bacterial contamination.

Algae Certain species of algae (blue-green algae) can, under some circumstances, be toxic. At present, there is no test available for these toxins. Other than possible toxicity, the presence of algae in livestock water supplies will affect livestock indirectly by discouraging consumption due to reduced palatability (taste and odor). Algae blooms can be prevented from occurring in a water supply by aerating the water and by preventing excess nutrients (phosphorus, nitrogen) from entering the water. Copper sulfate, zinc sulfate, chlorine bleach and shade are also effective in killing algae. The primary sources of nutrients that contribute to aquatic plant growth are animal excrement, fertilizers and organic matter like grass, hay, leaves and topsoil.



Other Factors Generally speaking, any surface water that can support a population of fish should not have dangerous levels of pesticides or naturally-occurring toxic elements like heavy metals. However, there is growing evidence that toxic compounds are present in many surface waters across the prairies. If there is any reason to believe that a water source may have elevated levels of toxic compounds, they can be tested.

It is recommended that water samples from the intended source be analyzed to ensure that any problems relating to water quality can be avoided.

The most common factors to consider are salinity and nitrates. Tables 2.1 and 2.2 describe tolerable levels of these elements.

Water Quality Testing

Consider testing for water quality if Total Dissolved Solids (TDS) levels are above 3000 ppm. Water quality testing can be done in accordance with Practice Standard, Groundwater Testing (Code 355). Test results can be interpreted with the assistance of Environmental Technical Note, MT-1 (Rev 2), Assessing Water Quality for Human Consumption, and Agriculture, Aquatic Live Uses.

Table 2.1 USE OF SALINE WATER FOR LIVESTOCK

Total Dissolved Solids mg/l

1,000-3,000 mg/l Very satisfactory for all classes of livestock. May cause temporary and mild diarrhea in livestock not accustomed to them.

3,000-5,000 mg/l Satisfactory for livestock but may cause diarrhea or be refused at first by animals not accustomed to them.

5,000-7,000 mg/l Can be used with reasonable safety for dairy and beef cattle, sheep, swine, and horses. Avoid use for pregnant or lactating animals.

7,000-10,000 mg/l Considerable risk in using for lactating cows, horses, sheep, or for the young of these species. In general, use should be avoided although older ruminants, horses, and swine may subsist on them under certain conditions.

Over 10,000 mg/l Risks with these highly saline waters are so great that they cannot be recommended for use under any conditions.



Table 2.2 EFFECTS OF NITRATES ON LIVESTOCK

1Undersander, Combs, Shave and Thomas, Nitrate Poisoning in Cattle, Sheep and Goats, University of Wisconsin Extension Paper.

2Guide to the Use of Waters Containing Nitrate for Cattle (National Academy of Sciences, 1974). 3Milligrams per liter (mg/l) is equivalent to parts per million (ppm). 4Cattle should not have access to these waters.

For additional information related to water quality see the MU Guide G 381 from the University of Missouri-Columbia “Water Quality for Livestock Drinking” located at the following web address: http://extension.missouri.edu/explorepdf/envqual/eq0381.pdf

Guidelines for use of drinking water with known nitrate content Nitrate

Nitrogen NO3-N

Nitrate Ion NO3 Comment

Acceptability2 ppm3

SAFE

<10 <44 Generally regarded as safe for all animals and humans.

10 to 20 44 to 88

Questionable or risky for humans, especially young children and pregnant women. Safe for livestock unless feed also has high levels. Animal drinking 10 pounds of water per 100 pounds of body weight would have intake of less than 0.1 gram NO3-N per hundred pounds of weight if water contains 22 ppm NO3-N.

20 to 40 88 to 176

Consider unsafe for humans. Might cause problems for livestock. If ration contains more than 1000 ppm nitrate- nitrogen (NO3-N) and the water contains over 20 ppm, the total NO3-N is likely to exceed safe levels.

QUESTIONABLE

40 to 100 176 to 440 Unsafe for humans and risky for livestock. Be sure to feed is low in nitrates and be sure a well-balanced ration is fed. Fortify ration with extra vitamin A.

100 to 200 440 to 880

Dangerous and should not be used. General or nonspecific symptoms such as poor appetite likely to develop. Water likely to be contaminated with other foreign substances. When allowed free choice to cows on a good ration, acute toxicity not likely.

UNSAFE4 Over 200 Over 880

Don’t Use. Acute toxicity and some death losses might occur in swine. Probably to too much total intake for ruminants on usual feed. In research trials, water containing up to 300 ppm NO3-N has been fed to swine and water containing over 1000 ppm of NO3-N has been fed to lambs without causing any measurable growth or reproductive problems. However, for farm recommendation the suggestions given above are purposely conservative.



PART 2.4 WATER QUANTITY REQUIREMENTS

The quantity of supplemental stockwater required during any given period depends on the type and number of stock, climatic conditions and amount of natural water available. It has also been found that water usage is higher for stock in an intensive grazing system.

The recommended daily water requirements of livestock in Montana are shown in the following tables: Table 2.3 provides guidelines pertinent to water requirements of water facilities. Table 2.4 provides guidelines pertinent to spacing of facilities.

Table 2.3 MINIMUM DAILY STOCKWATER REQUIREMENTS 1,2,3

Livestock Type Watering Facility for

Conventional Grazing System (gal/day)

Watering Facility for Intensive Grazing System (gal/day)

Range Cow 15 20

Cow and Small Calf 20 25 Dairy Cow (lactating) 25 30 Horse 15 20 Buffalo 20 25 Sheep 1.5 3 Goats 1.5 3 Hogs 1.5 3 Deer 1.5 - Antelope 1.5 - Elk 6 -

1These are minimum volumes. If livestock are larger than average, if livestock will be grazing areas that are extremely hot and arid, or if there are other planning issues, the volume of storage should be increased accordingly.

2Daily water consumption for feeder cattle or winter use may be calculated at 1 gallon per day per 100 lbs. 3For summer conditions, a minimum of 2 gallons per day per 100 lbs. is recommended for cattle. There will usually be water lost to evaporation and spillage at drinking tanks and troughs. Evaporation from a water surface can amount to as much as 0.30 inches per day or 9.0 inches per month in many parts of Montana during the summer months of the year. In intensive water facility applications, the livestock will water more often and more spillage will occur. It is critical that the water supply meets the water demand. To account for these losses and demand, the minimum daily water requirements shown in Table 2.3 were increased for intensive water facility applications.

See also North Dakota State University Extension’s publications AS-954 “Livestock and Water” and AS-1763 “Livestock Water Requirements” for additional guidance on water use rates for different livestock.



Table 2.4 RECOMMENDED MAXIMUM TRAVEL DISTANCE TO WATERING FACILITIES

Type of Terrain Conventional Grazing System Water Facility Maximum Travel

Distance

Intensive Grazing System Water Facility Maximum Travel

Distance1

Rough ½ mile 1/8 mile (660 feet) Rolling ¾ mile 1/6 mile (880 feet) Level 1 mile ¼ mile 2

Note: When two or more tanks are located in one pasture, tank spacing should be no farther than twice the travel distance. (i.e., 1 mile travel distance would be 2 miles tank spacing). 1Livestock must be checked daily. 2Assumes there are no visual obstructions in any direction between the livestock and the watering facility. If there are visual obstructions for an intensive water facility application, then use maximum travel distance of 1/6th mile, same as for rolling terrain.



PART 2.5 DESIGN FLOW RATE

The minimum pipeline design flow rate must be at least equal to the flow rate, in gallons per minute, required to provide the peak daily water requirements in a 24-hour period, for the maximum number of livestock in the pasture. It is often desirable to design for a higher flow rate to allow tanks to refill more rapidly during times of peak usage. Reasonable practice is to design pipeline flow rates to provide the full daily water needs in a 4-hour, 6-hour, or 12-hour period.

Figures 2.2 through 2.4 show flow rates required to meet daily needs in a 4-hour, 6-hour, and 12-hour period. These charts assume a 10 percent loss for evaporation and waste.

Figure 2.2 FLOW RATE REQUIRED FOR DAILY NEEDS (SUPPLIED IN 4 HOURS)

Based on Additional 10% for Evaporation and Waste Required Flow Rate Supplied in 4 hours

Number of Stock Using System

EXAMPLE:

Given: Conventional grazing system with 200 Dairy Cows. Find: Design flow rate meeting daily water requirements in a 4-hour period.

Solution:

From Table 2.3: 25 gal/day/head required during peak use period. From Figure 2.2: Minimum flow requirement is 22.9 gpm.





EXAMPLE:

Given: Conventional grazing system with 300 Cows. Find: Design flow rate meeting daily water requirements in a 6-hour period.

Solution:






EXAMPLE:

Given: Conventional grazing system with 150 Cow/calf pairs. Find: Design flow rate meeting daily water requirements in a 12-hour period.

Solution:




The Montana worksheet MT-ENG-20 summarizes the design procedures for calculation of the design flow rate computation and storage requirements for livestock water. An example is shown in Figure 2.5. Blank worksheets are available on MT NRCS website.

Figure 2.5

U.S. Department of Agriculture MT-ENG-20

Natural Resources Conservation Service Rev. 12/02

STOCKWATER PIPELINE RESOURCE INVENTORY WORKSHEET

Land user Joe Stockman Field Office XXX

Job description XXX

Location Sec XX TXXN RXXW Planner ABC Date xx/xx Checked by CBA Date xx/xx

Type of livestock Cow-calf Type of grazing system: x Conventional Intensive Maximum number of livestock (No.) 200 Typical date(s) stock will be in field: From June to August Water requirements per head (V) 20 gal/day/head at peak use. Total usage per day (T) = No. x V = 200 x 20 = 4000 gal/day. Desired number of hours for entire days needs to be delivered: Add 10% for evaporation and spillage: (GT) = T x 1.1 (optional)

GT = 4000 x 1.1 = 4400 gal/day MSPM Table 2.3 Minimum required flow rate (Qm) =. GT = 4400 = 3.06 gpm. 1440 1440 TOT (Total Operating Time/Day) = _____12______hrs Design Flow Rate: (Q) = 24 x Qm TOT

Q= 24 x 3.06 Q= 6.12 _____ gpm MSPM Fig 2.4

___12___ (TOT) Desired reserve storage time (RST) = 1 days Electric Power on Grid. MSPM Table 2.5 Total reserve storage required: (RS) = RST x GT RS = 1 x 4,400 = 4,400 gallons total storage in pasture. Other water sources available in the field: NONE

Dependability of water sources: Electric power on grid-good. Well yield is 12 gpm

Quality of water sources: Adequate for livestock.

Comments: NONE



PART 2.6 WATER STORAGE AND DRINKING SPACE REQUIREMENTS

2.6.1 General Discussion of Storage Volume and Drinking Space

The capacity of the water storage facilities within a pasture must be determined on an individual basis in close consultation with the operator. Adequate storage capacity shall be required to provide reserve storage (emergency storage) to the watering facility during times when water cannot be delivered to the facility. This storage may be supplied by gravity flow from an external storage tank or reservoir or within the facility itself. The storage amount should be based on location of the facility and local power considerations.

The size of watering facilities should be based upon storage, volume, and access space. Minimum storage volume required depends on the reliability of the source, herd watering habits, the hazards of exposure of the pipeline, management provided by the operator, and how easy it is to move livestock if the water supply fails. Additionally, the facility needs to be sized to provide adequate space for the number of animals expected to use the facility at any given time. These factors should be thoroughly discussed with the operator.

Table 2.5 shows approximate total stockwater requirements during a peak usage day. This table provides for an additional 10 percent allowance for evaporation and spillage.

Table 2.5 TOTAL DAILY STOCKWATER REQUIREMENTS

Gallons/Day Based on Additional 10% for Evaporation and Waste

Number of Stock Using System

WATER REQUIREMENTS - Gallons/Day/Head 2 8 12 15 20 25

25 55 220 330 413 550 688 50 110 440 660 825 1,100 1,375 75 165 660 990 1,238 1,650 2,063 100 220 880 1,320 1,650 2,200 2,750 125 275 1,100 1,650 2,063 2,750 3,438 150 330 1,320 1,980 2,475 3,300 4,125 175 385 1,540 2,310 2,888 3,850 4,813 200 440 1,760 2,640 3,300 4,400 5,500 250 550 2,200 3,300 4,125 5,500 6,875 300 660 2,640 3,960 4,950 6,600 8,250 350 770 3,080 4,620 5,775 7,700 9,625 400 880 3,520 5,280 6,600 8,800 11,000 450 990 3,960 5,940 7,425 9,900 12,375 500 1,100 4,400 6,600 8,250 11,000 13,750 600 1,320 5,280 7,920 9,900 13,200 16,500 700 1,540 6,160 9,240 11,550 15,400 19,250 800 1,760 7,040 10,560 13,200 17,600 22,000 900 1,980 7,920 11,880 14,850 19,800 24,750

1000 2,200 8,800 13,200 16,500 22,000 27,500



Table 2.6 shows round tank storage volumes and tank perimeters.

Table 2.6 ROUND STOCK TANK STORAGE CAPACITY & PERIMETER 1,2

Gallons Tank

Diameter (feet)

TANK DEPTH (feet) (Filled to within 3" of top)

TANK PERIMETER

(feet) 1.0 1.5 2.0 2.5 3.0 4 70 117 164 211 258 12.6 6 159 264 370 476 582 18.8 8 282 470 658 846 1,034 25.1 10 441 734 1,028 1,322 1,615 31.4 12 634 1,057 1,480 1,903 2,326 37.7 15 991 1,652 2,313 2,974 3,635 47.1 20 1,762 2,937 4,112 5,287 6,462 62.8 25 2,754 4,589 6,425 8,261 10,096 78.5 30 3,965 6,609 9,252 11,896 14,539 94.2 36 5,710 9,516 13,323 17,130 20,936 113.0 40 7,049 11,749 16,448 21,148 25,847 125.6

1Tank configuration should also be considered. Calves generally will not be able to reach water much deeper than 20 inches below the top of the tank. Therefore, only the water stored in the upper 20 inches of the tank would be considered as available water unless a separate tank is provided for calves.

2When using a tank not similar to the above round stock tank (i.e., rubber tire tank), use sound engineering judgment or appropriate worksheets to determine available storage.

GUIDANCE FOR WATERING FACILITY (TANK) STORAGE

2.6.2 Undependable Water Supply

Undependable water supplies are defined as water sources that are inspected infrequently, have high maintenance requirements, or have power requirements that are not dependable (solar, wind, undependable spring, etc.). Unreliable water supply systems require a minimum of three days of storage volume in each pasture from all reliable and accessible water sources within the pasture (tanks and surface water).

If the site is remote and inspected infrequently the minimum storage should be increased. Number of days’ storage will be dictated by the days between planned inspections of the site. See Table 2.7 for recommended reserve storage for different scenarios.

Note: If a system with an undependable water supply includes a centralized storage tank, with at least 3 days of storage volume, the storage tank can gravity flow to the pastures, and even if no other water is available, then the watering tanks within the pastures can be sized as they would for a dependable water source. The centralized storage tank can be counted as part of the storage for each pasture, thereby decreasing the size of the watering tank in the pasture. See the next section on Dependable Water Supply.

2.6.3 Dependable Water Supply

Examples of dependable water supplies are water systems that are supplied by an electrical power system on the grid, gravity pipelines from a perennial surface water, or a high-producing spring



development. Systems with a central storage tank with 3 days storage, where the water can flow via gravity to the pasture tanks can also be considered a dependable water supply.

Watering facilities in pastures with a dependable water supply can be designed based on stock density, water access perimeter, available flow rate, and grazing system criteria. For conventional grazing systems, the minimum recommended pasture storage in pastures with dependable water shall be equal to the daily water requirement minus the system flow rate delivered in 6 hours. Consider allowing for a minimum of a one-half day storage in each pasture if the system might be checked irregularly, the site is remote, or other water sources are not immediately available.

2.6.4 Conventional Grazing-Low Stock Density

These systems include relatively large herds in typically large pastures and are characterized by lower stock densities (typical stock densities are less than 0.5 animals per acre and stocking rates are often less than 0.8 animal unit month (AUM)/acre, Bailey, et al., 2004, Roath, et al., 1982). While it is difficult to predict what size group will come to water at one time, cattle in these situations tend to form smaller social groups (Roath, et al., 1982). Also, cattle will normally not wait to water into the late night hours (Roath, et al., 1982, Dwyer 1961, Bailey, et al., 2004). For conventional, low-stock density systems, the pipeline flow rate needs to provide the daily water need in 12 hours. Pasture storage volume all equal the daily water requirement minus the system flow rate delivered in 6 hours.

2.6.5 Conventional Grazing-Moderate Stock Density

These systems include relatively smaller herds, in moderate to smaller pastures, and are characterized by more moderate stocking densities (typical stock densities are often greater than 0.5 animals per acre, and stocking rates are generally greater than or roughly equal to 0.8 AUM/acre, Porath, et al., 2002, Plumb, et al., 1984). For conventional, moderate-stock density systems, the ideal design will provide pasture storage volume for half of the daily water need minus the system flow rate in one hour. This will minimize the amount of time the cattle will loaf around the watering facility and maximize the time spent grazing in the pasture. The minimum flow rate needs to provide the daily water need in 24 hours.

For watering facilities spaced less than 1.0 mile apart (rough terrain), 1.5 miles (rolling terrain), and 2 miles (level terrain), the storage volume and access space in each facility can be added together to meet the minimum storage volume and access space. If the facilities are further apart than the distances listed above, each facility should be considered as the sole source of water in the pasture, and be sized to meet the minimum storage volume and access space. Consideration should be given to the fact that cattle trailing and subsequent erosion may be increased with increased distances to water. Also, grazing distribution may not be as even with increased distance to water.

2.6.6 Management Intensive Systems

Systems managed intensively tend to have smaller pastures with watering facilities spaced closely. These systems are characterized by high stock densities (typical stock densities are often greater than one animal per acre, while stocking rates are variable, Hacker, et al., 1988, Walker, et. al., 1989,) and animals are moved more frequently than in conventional systems. The animals will come to water in singles and pairs as long as the water source is reliable and travel distance to water is not excessive (Bingham 2005). Because of this tendency, the total amount of water consumed is less at a time and limited by the number of animals at the watering facility. If these systems are supplied by pipelines capable of delivering the peak demand of the animals, the watering facility will require very little storage.

Cattle will drink at a rate up to two gallons per minute. The preferred design approach for intensive systems is to supply the water at a rate of 2 gpm per drinking space in order to minimize water tank storage. When the available flow is greater than 2 gpm per drinking space, the watering tank will not have a storage requirement, however enough drinking space perimeter will need to be provided. When the available flow is less than 2 gpm/drinking space, the minimum pasture storage will be equal to the daily water requirement minus the 6-hour inflow volume.



2.6.7 Winter Feeding Areas

For winter feeding areas, calving areas, or feedlots, stock tanks or fountains with minimal storage may be used. At a minimum, the pipeline shall provide the daily water requirement to the maximum confined animal numbers within an 8-hour period. Winter waterers shall provide at minimum, one drinking space per 100 cattle. For feedlots without storage, consider a flow rate of 2 gpm per drinking space.

Consider a documented contingency plan for winter feeding areas or feedlots served by stock tanks or fountains with minimal storage or pipeline capacity unable to deliver 2 gpm per drinking space. Without a contingency plan, consider a tank volume providing the daily water requirement minus the 6-hour inflow volume.

2.6.8 Reserve Storage

Adequate reserve storage volume for each pasture is required to provide adequate water during emergencies when water from the stockwater system cannot be delivered to the tanks. This storage may be supplied by gravity flow from an external storage tank or by making surface waters within the pasture accessible to the livestock. For instance, if a stream running through the pasture is normally fenced out, gates could be open in the riparian fencing to give the cattle access to this stream in an emergency. The storage amount should be based on location of the facility and local power considerations.

The determination of adequate reserve storage volume is a management decision that should be made with the operator after thorough discussion of all factors involved. Consideration should be given to how often the operator will inspect the site and travel time to get to the site. Utilization of remote sensing monitoring systems will also be a consideration as to how many days of reserve storage are needed. All water sources within the pasture may be used in determining reserve storage volume. The following reserve storage volumes listed in table 2.7 on the next page are recommended:

Table 2.7 RESERVE STORAGE REQUIREMENT 1,2

Reserve Storage Time Days

Wind Powered System 3

Wind Powered-remote 4-7

Spring-Gravity Flow (undependable or variable) 3-7

Petroleum Generator or Pump Remote 3

Solar System 3

Solar System-Remote 4-7

Electric on Power Grid - Remote 1.5

Electric, Petroleum or solar system (checked daily) 1

Spring-Gravity Flow (dependable) 1 1 All systems with one (1) day storage requirements should be checked daily and should meet one of the following: adjoined pastures are close enough that livestock can be easily moved to dependable water; pastures are close enough to haul daily water; backup generators are in place for solar electric systems. These items shall be documented in the O&M plan.

2Reserve Storage may include a storage tank or other water sources, such as ponds and streams that can be made available to the livestock.



2.6.9 Water Access Perimeter

The water access perimeter needs to be sized to provide adequate space for the number of animals expected. The following values are considered adequate for meeting cattle access requirements:

• Provide one space for every 20 animals (5 percent of herd) when water is available in each pasture/field and livestock generally drink one at a time or in small groups. Generally, travel distances should be less than 1980 feet from the tank to the edge of the pasture/field.

• Provide one space for every 10 animals (10 percent of herd) to drink at one time at a tank where travel distances are greater than 1,980 feet, at a centralized water supply, or in areas where animals will congregate and fight for access to tank.

• For winter feeding areas, calving areas, or feedlots, watering facilities shall provide at least one drinking space per 100 head of cattle. Winter watering tanks sometimes have access holes in the lids or floats covering the openings. Each of these openings would be considered a drinking space.

• Allow 18 inches of perimeter for circular tanks and 24 inches for straight side tanks per animal.

Tank perimeter lengths for various circular tanks are listed in Table 2.6.



PART 2.7 EXAMPLES

Example 1A: TYPICAL PRESSURE SYSTEM-UNKNOWN STOCK DENSITY

GIVEN: Standard pressure system using electric power on the grid at a remote site. One herd of 80 cow/calf pairs, conventional grazing, four pastures, no storage tank, reliable surface water is available in all pastures but riparian area is fenced, maximum travel distance < 1980 feet. Flow delivered by pump and pipeline is 3 gpm.

FIND: Tank Sizes required.

Compute Daily Water Need = 80 pairs x 20 gal/day/pair = 1600 gal/day. Add 10% to daily needs for evaporation and spillage 1600 gal/day x (1.1) = 1760 gal/day (or find value in Table 2.5).

Check that Flow Delivered Meets Minimum Required Flow. Minimum flow is the daily water need being delivered in 24 hours:

Qmin = 1760 gal/day = 1.22 gpm < 3 gpm, which is available from pump. OK 1440 min/day

Determine Pasture Storage: Pasture Storage = daily water needs – volume delivered by pipeline in 6 hours: 1760 gal – (6 hour)x(60 min/hour)x(3 gal/min) = 680 gal. minimum in each pasture. (We may want to consider a one-half day storage in each pasture based on management practices, regularity of inspections, other available water, etc. - one-half day storage = 1760 gal/2 = 880 gal).

Choose Tank Size: From Table 2.6, one 2-foot deep x 10’ diameter tank has a storage of: 1028 gal > 680 gal (minimum pasture storage) and > 880 gal (if one-half day storage is desired). OK

Check Tank Perimeter: Maximum travel distance < 1980 feet. Therefore design for 5% of herd 0.05 x 80 = 4 animals (or 4 drinking spaces). For Circular Tanks-one drinking space = 18 inches: (1.5 ft/space)x(4 spaces) = 6 feet of perimeter needed.

From Table 2.6: a 10-foot diameter tank has perimeter = 31.4 feet > 6 feet. OK

Check Water Storage Available to Calves: Consideration: When calves only reach top 20 inches. Usable Depth = 20 inches – 3 inches Freeboard = 17 inches = 1.42 feet Top area = π x (D2)/4 = π (102)/4 = 78.5 feet; Storage in 17 inches of water = (78.5 feet2)(1.42 feet) = 111.47 feet3. 111.47 ft3 x 7.48 gal/ feet3

= 834 gal. This is greater than minimum required of 680 gallons, but slightly less than 880 gallons (if we were concerned about providing one-half day storage). But this is very close, so Calf storage is OK.

Use one 10-foot diameter x 2-foot deep tank in each pasture.

Check Reserve Storage for Pasture: From Table 2.7, for Electric on Power Grid-Remote site, want 1.5 days of reserve storage: 1760 gal/ day x 1.5 days = 2640 gal Riparian fences can be removed in an emergency. Creek volume > 2640 gallons OK.

BUT WHAT IF THERE WERE NO OTHER WATER AVAILABLE, NO RIPARIAN AREA TO OPEN UP ACCESS TO: Then, we would recommend that each pasture tank provide 2640 gallons to meet reserve storage.



Example 1B: TYPICAL PRESSURE SYSTEM-LOW STOCK DENSITY

GIVEN: Standard pressure system using electric power on the grid at a remote site. One herd of 80 cow/calf pairs, conventional grazing, low density, four pastures, no storage tank, reliable surface water is available in all pastures but riparian area is fenced, maximum travel distance < 1980 feet. Flow delivered by pump and pipeline is 3 gpm.


Compute Daily Water Need = 80 pairs x 20 gal/day/pair = 1600 gal/day. Add 10% to daily needs for evaporation and spillage 1600 gal/day x (1.1) = 1760 gal/day (or find value in Table 2.5).

Check that Flow Delivered Meets Minimum Required Flow: Because this is a low density situation, supply the daily water needs in 12 hours. Qmin = 1760 gal/day x 24 = 2.4 gpm < 3 gpm, which is available from pump. OK 1440 min/day 12

Determine Pasture Storage: Pasture Storage = daily water needs – volume delivered by pipeline in 6 hours: 1760 gal – (6 hour)x(60 min/hour)x(3 gal/min) = 680 gal. minimum in each pasture.

Choose Tank Size: From Table 2.6, one 2-foot deep x 10-foot diameter tank has a storage of: 1028 gal > 680 gal (minimum pasture storage) and > 880 gal (if one-half day storage is desired). OK

Check Tank Perimeter: Maximum travel distance < 1980 feet. Therefore design for 5% of herd 0.05 x 80 = 4 animals (or 4 drinking spaces). For Circular Tanks-one drinking space = 18 inches:

(1.5 feet/space)x(4 spaces) = 6 feet of perimeter; From Table 2.6: a 10-foot diameter tank has perimeter = 31.4 feet > 6 feet. OK

Check Water Storage Available to Calves: Consideration: When calves only reach top 20 inches.

Usable Depth = 20 inches – 3 inches Freeboard = 17 inches = 1.42 feet Top area = π x (D2)/4 = π (102)/4 = 78.5 feet2; Storage in 17 inches of water = (78.5 feet2)(1.42 feet) = 111.47 feet3. 111.47 feet3 x 7.48 gal/ feet3 = 834 gal. This is greater than minimum required of 680 gallons, but slightly less than 880 gallons for one-half day. Calf storage is OK.

Use one 10-foot diameter x 2-foot deep tank in each pasture.

Check Reserve Storage for Pasture: From Table 2.7 for Electric on Power Grid-Remote site, want 1.5 days of reserve storage: 1760 gal/day x 1.5 days = 2640 gallons Riparian fences can be removed in an emergency. Creek volume > 2640 gallons. OK




Example 1C: TYPICAL PRESSURE SYSTEM-MODERATE STOCK DENSITY

GIVEN: Standard pressure system using electric power on the grid at a remote site. One herd of 80 cow/calf pairs, conventional grazing moderate stocking density, four pastures, no storage tank, reliable surface water is available in all pastures but riparian area is fenced, maximum travel distance < 1980 feet. Flow delivered by pump and pipeline is 3 gpm.


Compute Daily Water Need = 80 pairs x 20 gal/day/pair = 1600 gal/day. Add 10% to daily needs for evaporation and spillage 1600 gal/day x (1.1) = 1760 gal/day.

Check that Flow Delivered Meets Minimum Required Flow. Minimum flow is the daily water need being delivered in 24 hours:

Qmin = 1760 gal/day = 1.22 gpm < 3 gpm, which is available from pump. OK 1440 min/day

Determine Pasture Storage: For moderate stock density, want pasture storage = one-half Daily water need volume – volume delivered by pipeline in 1 hour:

(1760 gal/day ÷2) – (3 gal/min)x(1 hour)x(60 min/hour) = 700 gal. in each pasture.

Choose Tank Size: From Table 2.6, one 1.5-foot deep x 10-foot diameter tank has a storage of: 734 gal > 700 gal (minimum pasture storage). OK

Check Tank Perimeter: Maximum travel distance < 1980 feet. Therefore design for 5% of herd 0.05 x 80 pair = 4 animals (or 4 drinking spaces).

Check Water Storage Available to Calves: Consideration: When calves only reach top 20 inches. For 1.5 ft deep tank, calves can reach to bottom: Storage available to calves is 734 gallons. OK

NOTE: The 1.5-foot deep x 10-foot diameter tank would not be adequate if we desired one-half day storage (1760 gal/2 = 880 gallons) in each pasture.

Use one 10-foot diameter x 1.5-foot deep tank in each pasture.

Check Reserve Storage for Pasture: From Table 2.7, for Electric on Power Grid-Remote site, want 1.5 days of reserve storage: 1760 gal/ day x 1.5 days = 2640 gallons.

Riparian fences can be removed in an emergency. Creek volume > 2640 gallons. OK




Example 2: TYPICAL PRESSURE SYSTEM-LONG TRAVEL DISTANCE

GIVEN: Typical pressure system using electric power on the grid at remote site. 100 cow/calf pairs, conventional grazing, low density, one large pasture, no storage tank, no other water available. Pasture is rolling terrain and tanks will be spaced greater than 1.5 miles. Pump and pipeline deliver 5 gpm. Want to use 3 tank sites in this pasture.

FIND: Tank Sizes.

Compute Daily Water Need = 100 pair x 20 gal/day/pair = 2000 gal. Add 10% to daily needs for evaporation and spillage: 2000 gal/day x 1.1 = 2200 gallons (or use Table 2.5) Check that Flow Delivered Meets Minimum Required Flow: Minimum flow is the daily water need delivered in 12 hours: Qmin = 2200 gal/day x 24= 3.06 gpm < 5 gpm available. OK 1440 min/day 12

Determine Pasture Storage: See Table 2.4 for maximum travel distance. For rolling terrain, maximum travel distance is three-quarter mile. Since the tanks are spaced greater than 1.5 miles, travel distance will be greater than the three-quarter mile recommended. Thus, each tank should be considered as the sole source of water. The storage volume and perimeter will be based on 100 animals at each tank site.

Pasture Storage = daily water needs – volume delivered by pipeline in 6 hours: 2200 gal – (6 hour)x(60 min/hour)x(5 gal/min) = 400 gal.

Check Tank Perimeter: Maximum travel distance > 1980 feet. Therefore design for 10% of herd 0.1 x 100 head = 10 animals (or 10 drinking spaces) For Circular Tanks-one drinking space = 18 inches. (10 spaces) x 1.5 feet = 15 feet perimeter is needed.

Choose Tank Size: From Table 2.6: one 2-foot deep x 8-foot diameter tank has perimeter = 25 feet > 15 feet. OK

Check Water Storage Available to Calves: As a consideration, calves only reach top 20 inches. Usable Depth = 20 inches – 3 inches Freeboard = 17 inches = 1.42 feet Top area = π x (D2)/4 = π (82)/4 = 50.26 feet2; Storage in 17 inches of water = (50.26 feet2)(1.42 feet) = 71.37 feet3. 71.37 feet3 x 7.48 gal/ feet3 = 534 gal.

534 gallons available to calves > 400 gallons minimum required.

Each tank site in the pasture will have one 2-foot deep x 8-foot diameter tank.

Check Reserve Storage: From Table 2.7 - Electric on Power Grid-Remote site, requires 1.5 days reserve: 2200 gal/day x 1.5 days = 3300 gal.

Total pasture storage: Will have three tank sites in the pasture: 3 tanks x 400 gal/tank = 1200 gallons. May want to consider adding more storage in the pasture to meet reserve storage recommendations.



Example 3: TYPICAL TIMER SYSTEM-CENTRAL STORAGE TANK

GIVEN: 150 cow/calf pairs, conventional grazing, low density stocking rate, one herd, four pastures, no other water is available, maximum travel distance = 2500 feet. Design flow from pump to storage tank is 5 gpm. Gravity flow from storage tank to all pasture tanks is 5 gpm. Storage Tank has a volume of 5000 gallons.

FIND: Determine tank sizes for a standard timer system using electric power on grid at remote site.

Compute Daily Water Need: 150 pairs x 20 gal/pair = 3000 gal. Add 10% to daily needs for evaporation and spillage 3000 gal/day x (1.1) = 3300 gal/day.

Check that Flow Delivered Meets Minimum Required Flow: Minimum flow is the daily water need being delivered in 6 hours: Qmin = 3300 gal/day x 24= 4.6 gpm < 5 gpm available. OK 1440 min/day 12

Determine Pasture Storage: Pasture Storage = daily required volume – volume delivered by pipeline in 6 hours: 3300 gal – (6 hour)x(60 min/hour)x(5 gal/min) = 1500 gal. minimum in each pasture. Storage Tank offers 5000 gallons. The storage tank’s volume can be counted as pasture storage. 5000 gal > 1500 gal. OK

Check Tank Perimeter: Maximum travel distance > 1980 feet. Therefore design for 10% of herd 0.1 x 150 = 15 animals (or 15 drinking spaces).

For Circular Tanks-one drinking space = 18 inches: (1.5 feet/space)x(15 spaces) = 22.5 feet of perimeter needed.

Choose Tank Size: From Table 2.6, an 8-foot diameter x 2-foot deep tank has perimeter = 25.1 feet > 22.5 feet. OK

Check Water Storage Available to Calves: Consideration: Calves only reach top 20 inches. Usable Depth = 20 inches – 3 inches Freeboard = 17 inches = 1.42 feet Top area = π x (D2)/4 = π (82)/4 = 50.26 feet2; Storage in 17 inches of water = (50.26 feet2)(1.42 feet) = 71.36 feet3. 71.36 feet3 x 7.48 gal/ feet3 = 534 gal. 534 gallons < 1500 gallons minimum pasture storage. However, water from the storage tank can gravity flow to the stock tank. Thus, storage tank’s volume of 5000 gallons can be added to pasture volume: (5000 + 534 = 5534 gal) > 1500 gallons. Pasture storage is OK.

Use one 2-foot x 8-foot diameter tank in each pasture.

Check Reserve Storage for Pasture: From Table 2.7 - For Electric on Power Grid-Remote site, want 1.5 days of reserve storage: 1.5 days x 3300 gal/day = 4950 gal. Storage tank volume > 4950 gal. OK



Example 4: SOLAR SYSTEM-NO STORAGE TANK

GIVEN: Solar-powered pump system. 100 cows, conventional grazing, low density, one herd, four pastures, no storage tank, no other water sources, maximum travel distance = 2000 feet.

FIND: Tank Sizes.

A solar-powered pump system would be considered an “undependable” water source. Therefore the minimum storage in each pasture would be three days.

Compute Daily Water Need = 100 head x 15 gal/head/day = 1500 gal/day. Add 10% to daily needs for evaporation and spillage: 1500 gal/day x (1.1) = 1650 gal/day (or find value on Table 2.5).

Determine Pasture Storage: For undependable water source, need three days of storage volume. Minimum Pasture Storage = 1650 gal/day x 3 days = 4950 gal.

Choose Tank Size: From Table 2.6: one 2-foot deep x 25-foot diameter tank stores 6425 gal. OR might choose five 2-foot deep x 10-foot diameter tanks. From Table 2.4, one stores 1028 gallons; 5 tanks x 1028 = 5140 gallons or other combinations.

Check Flow Rate: Need to make sure minimum flow is achieved from solar unit. Check volume of water pumped per day versus solar insolation charts from solar pump manufacturer.

Check Tank Perimeter: Travel Distance > 1980 feet. Therefore design for 10% of herd 0.1 x 100 head = 10 animals (or 10 drinking spaces). For Circular Tanks-one drinking space = 18 inches. (10 spaces) x 1.5 feet = 15 feet. From Table 2.6 a 25-foot diameter tank has 78.5 feet of perimeter. And five 10-foot diameter tanks have total perimeter of 157 feet >>>> 15 feet. OK

Use either one 2-foot x 25-foot diameter tank OR five 2-foot x 10-foot diameter tanks in each pasture.

Check Reserve Storage for Pasture: From Table 2.7 - For Solar System want minimum of three days of storage. 3 days x 1650 gal/day = 4950 gallons. The tank combination options listed above will provide more than 4950 gallons. OK



Example 5: SOLAR SYSTEM-CENTRAL STORAGE TANK

GIVEN: Solar-powered pump system. 100 cows, conventional grazing, low density, one herd, four pastures, central storage tank, no other water sources, maximum travel distance = 2000 feet. Central storage tank can gravity flow to all pasture tanks at a rate of 3 gpm.

FIND: Tank Sizes.

A solar-powered pump system would be considered an “undependable” water source. Therefore the minimum storage in each pasture would be three days.

Compute Daily Water Need = 100 head x 15 gal/head/day = 1500 gal/day. Add 10% to daily needs for evaporation and spillage: 1500 gal/day x (1.1) = 1650 gal/day

Determine Pasture Storage: Minimum Pasture Storage = 1650 gal/day x 3 days= 4950 gal. Choose a Storage tank with a volume = 5000 gal.

Check that Flow Delivered to Pasture Meets Minimum Required Flow. Minimum flow is the daily water need being delivered in 12 hours: Qmin = 1650 gal/day x24= 2.3 gpm <3 gpm available. 1440 min/day 12 OK

Also need to make sure minimum flow is achieved from solar unit. Check volume of water pumped per day versus solar insolation charts from solar pump manufacturer.

Check Tank Perimeter: A central storage tank with over three days of storage will provide water via gravity flow to each pasture. Thus the watering tank size in each pasture can be based on the drinking space perimeter. Travel Distance > 1980 feet. Therefore design for 10% of herd 0.1 x 100 head = 10 animals (or 10 drinking spaces) For Circular Tanks-one drinking space = 18 inches. (10 spaces) x 1.5 feet = 15 feet.

Choose Tank Size: From Table 2.6: one 2-foot deep x 6-foot diameter tank has 18.8 feet perimeter > 15 feet. OK Tank storage for one 2-foot deep x 6-foot diameter tank = 370 gallons of storage.

Total Pasture storage = 5000 gallons for storage tank + 370 gallons in watering tank = 5370 gal > 4950 gallons (3 days storage). OK

Use one 2-foot x 6-foot diameter tank in each pasture.

Check Reserve Storage: From Table 2.7 - A Solar System should have 3 days: 1650 gal/day x 3 days = 4950 gal.

Storage tank volume + watering tank volume = 5370 gallons > 4950 gal. OK.



Example 6: SOLAR SYSTEM - WITH OTHER AVAILABLE WATER

GIVEN: A solar system at remote site. 100 cow/calf pairs, conventional grazing, low density, one pasture, no storage tank, maximum travel distance to water = 2000 feet. There is a very reliable 30 acre-foot pond that can be accessed by livestock and will be used as one watering site. Three additional tank sites from a solar unit are desired in this pasture for proper grazing distribution.

FIND: Tank Sizes.

There will be four watering sites (three tanks plus one pond). If one assumes an equal distribution of livestock, there would be 25 cow/calf pairs at each site. Tank volumes and perimeters will be sized for the 25 pairs at each tank site: Total = 25 pairs x 3 tank sites = 75 cow/calf pairs.

Compute Daily Water Need for Pasture: 100 pair x 20 gal/day/pair = 2000 gal/day. Add 10% to daily needs for evaporation and spillage: 2000 gal/day x 1.1 = 2200 gal/day total pasture storage including pond site.

Compute Daily Water Need for Tank Sites Only: Can look at this as being three-quarter of the total pasture storage: 0.75 x 2200 gallons = 1650 gal/day OR Compute as follows: Tank sites will have 25 pair at each site x 3 tank sites = 75 pair

Daily water need just for the tanks = 75 pair x 20 gal/day/pair = 1500 gal. Add 10% to daily needs for evaporation and spillage: 1500 gal/day x 1.1 = 1650 gallons or use Table 2.5).

Check that Flow Delivered Meets Minimum Required Flow: The solar pump must provide for the daily needs of the 75 pair, or 1650 gallons per day. From the solar pump manufacturer, we check and find the solar pump will provide 1800 gal/day during the lowest output month of the grazing period. 1800 gal/day > 1650 gal/day. OK

Determine Pasture Storage (entire pasture, including the pond and thre tank sites): For solar systems a minimum of three days storage is required. 3 days x 2200 gal/day = 6600 gallons storage for entire pasture.

Determine Storage for Three Tank Sites Only. As in the computations for daily water need, the storage volume for the three tank sites is three-quarter x total pasture storage = 0.75 x 6600 gal = 4950 gallons.

The storage volume in the three tank sites combined should equal 4950 gallons. Thus each tank site will have a storage equal to 4950 gallons/3 tanks = 1650 gallons at each. From Table 2.6, one 2-foot x 10-foot tank has 1028 feet storage. 2 tanks x 1028 = 2056 gal > 1650 gal. OK

Check Storage Available to Calves: Consideration: Calves only reach top 20 inches. Usable Depth = 20 inches – 3 inches Freeboard = 17 inches = 1.42 feet; Top area = π x (D2)/4 =π x (102)/4 = 78.54 feet2 x 2 = 157 feet2; Storage in 17 inches of depth = (157)(1.42) = 22.94 feet3 = 1667 gal per tank site > 1650 gal. OK

Check Tank Perimeter: Maximum travel distance = 2000 feet > 1980 feet so design for 10% of herd. The herd size assumed at each tank is 25 pair. 0.1 x 25 head = 2.5 animals (or 3 drinking spaces).



For Circular Tanks-one drinking space = 18 inches. (3 spaces) x 1.5 feet = 4.5 feet perimeter is needed at each tank site.

From Table 2.6: Two 2-foot x 10-foot diameter tanks have perimeter of (2 tanks) x 31.4 feet = 62.8 feet >>>> 5 feet. OK

Use two 2-foot deep x 10-foot diameter tanks at each watering site.

Check Reserve Storage for Pasture: From Table 2.7 - For a Solar System in a Remote setting, want 7 days reserve storage: 7 days x 2200 gal/day = 15400 gal. Pond storage >>>> 15400 gal. OK

In this case, the pond is accessible and provides the adequate storage volume in the pasture if the solar unit fails.



Example 7a: MANAGEMENT INTENSIVE SYSTEM – HIGH FLOW

GIVEN: An intensive grazing system that runs 100 cow-calf pairs. Water source is a pressure system on the electric grid that provides 10 gpm.

FIND: Tank size for 100 cow-calf pairs.

For all management intensive systems, it is assumed that water is checked daily and the maximum travel distance is always less than 1320 feet (see Table 2.4).

The preferred design approach is to supply water at the rate cattle drink (2 gpm/drinking space).

Find Desired Flow Rate to Provide 2 gpm/Drinking Space: Find number of drinking spaces for which to design: Travel distance < 1980 feet. Therefore, design for 5% of herd. (100 pair)(.05) = 5 head (5 drinking spaces).

Desired Flow = 2 gpm/drinking space x 5 spaces = 10 gpm. OK. Pressurized water system will deliver 10 gpm.

Design Tank to Provide Enough Water Access Perimeter: For Circular Tanks-one drinking space = 18 inches: (1.5 feet)(5 spaces) = 7.5-foot perimeter needed. For Rectangular Tanks-one drinking space = 24 inches: (2.0 feet)(5 spaces) = 10-foot perimeter needed.

Option 1: 1 tank per pasture.

Select 1 circular tank with a perimeter as close to 7.5 feet as possible. Select 1 rectangular tank with a perimeter as close to 10.0 feet as possible.

Option 2: Select a number of waterers having enough drinking hole ports. Total number of drinking ports per pasture should be 5.

Because 2 gpm per drinking space is supplied, no storage is needed:

We can prove that no storage is needed with the following equations:

Compute Daily Water Need: 100 head x 25 gal/day/head = 2500 gal daily need. (Note that the extra evaporation and spillage created by an intensive grazing management system is already built into the higher water use rates, so adding 10% to the gal/day/head value is not necessary.)

Determine Pasture Storage Needed: Pasture storage is the daily water need minus volume delivered by pipeline in 6 hours:

Pasture storage = 2500 gal – (6 hour x 60 min/hour x 10 gpm) = - 1100 gal. Negative value = 0 Thus, no storage is required for flow rate delivering 2 gpm per drinking space.



Example 7b: MANAGEMENT INTENSIVE SYSTEM – LOW FLOW (Same as Example 7a, but assume the maximum available flow is only 2 gpm)

GIVEN: An intensive grazing system that runs 100 cow-calf pairs. Water source is a pressure system on the electric grid that provides 2 gpm.

FIND: Tank size for 100 cow-calf pairs.

Because 2 gpm/drinking space is not provided by the water system, a combination of flow and storage is required.

Compute Daily Water Needs: (100 pair)(25 gal/day/pair) = 2500 gal. (No need to add 10% for evaporation, because extra for spillage/evaporation is added in already for the 25 gal/day water use listed for intensive grazing systems.)

Check Minimum Required flow: Minimum Flow is daily water needs delivered in 24 hours: Qmin = 2500 gal/day = 1.7 gpm < 2 gpm available. OK 1440 min/day

Determine Pasture Storage: Pasture Storage = daily water need – volume delivered by pipeline in 6 hours: 2500 – (6 hours)(60min/hour)(2 gal/min) = 1780 gal.

One possibility is using a portable storage tank. Select a portable storage tank that can be moved from pasture to pasture (flatbed trailer, etc.) having a minimum volume of 1780 gal.

Choose a drinking tank that provides enough water access perimeter: Travel distance < 1980 feet. Design for 5% of herd. (100 pair)(.05) = 5 head (5 drinking spaces).

For Circular Tanks-one drinking space = 18 inches: (1.5 feet)(5 spaces) = 7.5-foot perimeter. For Rectangular Tanks-one drinking space = 24 inches (2.0 feet)(5 spaces) = 10-foot perimeter.

Option 1: One tank per pasture.

Select 1 circular tank with a perimeter as close to 7.5 feet as possible. Select 1 rectangular tank with a perimeter as close to 10.0 ten as possible.

Option 2: Select a combination of tanks having drinking hole ports. Total number of drinking ports per pasture should be 5.

Design the supply line so that it can be plumbed into the storage tank at desired locations (similar to a wheel-line). Plumb the storage tank into the watering tank at each site for gravity flow. Install float and overflow on the storage tank and watering tank.

If a storage tank is provided, then the watering tanks do not need to have storage.

Could also consider a permanent storage tank.



Example 8: MANAGEMENT INTENSIVE SYSTEM – CENTRAL STORAGE

GIVEN: 500 yearlings averaging 900 lbs. in an Intensive Grazing system. Available flow is 10 gpm.

FIND: Tank Sizes.

For all management intensive systems, it is assumed that water is checked daily and the maximum travel distance is always less than 1320 feet (see Table 2.4).

The preferred design approach is to supply water at the rate cattle drink (2 gpm/drinking space).

Find Desired Flow Rate to Provide 2 gpm/Drinking Space: Find number of drinking spaces for which to design: Travel distance < 1980 feet. Therefore, design for 5% of herd. (500 pair)(.05) = 25 head (25 drinking spaces).

Desired Flow = 2 gpm/drinking space x 25 spaces = 50 gpm. > 10 gpm available flow. Will need to use a combination of flow and storage.

Compute Daily water needs: From Note #3 in Table 2.3, use 2 gal/day per 100 lbs. Daily Volume = (2 gal/100 lbs.)(900 lbs./head)(500 head) = 9000 gal. Add 10% to daily needs for evaporation and spillage: 9000 gal/day x (1.1) = 9900 gal/day.

Check Minimum Required Flow: Minimum Flow is daily water needs delivered in 24 hours: Qmin = 9900 gal/day = 6.88 gpm < 10 gpm available. OK 1440 min/day

Determine Pasture Storage: Pasture Storage = daily required volume minus volume delivered by pipeline in 6 hours: 9900 – (6 hours)(60min/hour)(10 gal/min) = 6300 gal.

Select a central storage tank with a volume > 6300 gallons. Will gravity flow from the storage tank to all watering tank locations at a rate of 50 gpm to minimize storage in the watering tanks?

Design watering tanks to provide enough water access perimeter: Travel distance < 1980 feet. Design for 5% of herd. 500 head x 0.05 = 25 spaces. Each watering tank needs to provide enough perimeter access for 25 cattle. For Circular Tanks-one drinking space = 18 inches: (1.5 ft)(25 spaces) = 37.5 feet.

From Table 2.6, one 2-foot deep x 12-foot diameter watering tank has a perimeter of 37.7 feet > 37.5 feet.

Use a central storage tank with a volume equal or greater to 6300 gallons, and use one 2-foot x 12-foot watering tank in each pasture (or could consider a portable water tank that can be moved from pasture to pasture as needed).

NO minimum storage volume is required for the watering tank, because the storage is in the storage tank.



Example 9: WINTER FEEDING AREA EXAMPLE

GIVEN: A winter feeding area will confine 200 head of bred cows and heifers from January through April 30. Animal weight is about 1200 lb/cow. Well, pump, and pipeline are capable of supplying 6 gpm to tanks.

FIND: Adequate Waterer Sizes.

Compute Daily Water Needs: From Note #2 in Table 2.3, use 1 gal/100pounds per day for winter water use.

Daily Water Needs = 200 head x 1 gal/day/lb x (1200 lb/100) = 2400 gallons. Add 10% to daily needs for evaporation and spillage: 2400 gal x 1.1 = 2640 gal/day.

Check Minimum Required System Flow Rate: For winter feeding areas it is recommended to supply the daily water needs in 8 hours: Qmin = 2640 gal/day x 24 = 5.5 gpm < 6 gpm available. OK 1440 min/day 8

Minimum drinking space for winter feeding areas: For winter feeding areas and feedlots provide 1 space per 100 head: (200 head) x (1 space/100 head) = 2 spaces needed Most watering pans for winter waterers are rectangular. For Rectangular Tanks-one drinking space = 24 inches. Perimeter space needed: 24 inches per drinking space x 2 spaces = 48 inches = 4 feet

Can water system provide enough flow to waterers based on 2 gpm per drinking space? 2 spaces x 2 gpm/space = 4 gpm < 6 gpm that is provided by the water system. Therefore limited storage in watering trough is OK.

Use a manufactured waterer that has either two drinking ports, or if it is an open pan, that it has at least 48 inches of space around perimeter of drinking pan.

Also check the flow versus pressure charts of the float valve supplied in the waterer. Make sure 5 to 6 gpm can be supplied by the float at the available pressure.

chapter 2 − planning considerations€¦ · montana stockwater pipeline manual chapter 2 −...

Documents