Water Sources Final 1

1. Water Sources Presented by: New England Water Works Association Instructor: Sam Elliot, CET 703-403-6313 swelliot@hotmail.com

2. Water Sources Introduction Course will cover: Hydrologic cycle Description Terms Water ownership rights Groundwater Surface water Water quality concerns for water sources Conservation methods and water use Watershed protection

3. Water Sources Water Quality Concerns for Water Sources Physical Biological Chemical Radiological Source Protection Concepts Wellhead protection Surface water protection Watershed protection

4. Water Sources Groundwater Terms and well construction Types of wells Springs and infiltration galleries Well construction Aquifer types and performance Well operation and pumping

5. Water Sources Surface Water Water rights Watershed sources and characteristics Runoff and types of pollution Storage Challenges using surface water sources Alternative sources Use and conservation of water

6. Water Sources

7. Water Sources – Hydrologic Cycle The Hydrologic Cycle Evaporation and transpiration Condensation Precipitation Infiltration, percolation surface runoff

8. Water Sources – Hydrologic Cycle Evaporation Water becomes a gas – evaporation Heat from the sun causes most evaporation Sublimation – ice directly to vapor Transpiration Water is absorbed by plants Returns to air from leaves and blades of grass

9. Water Sources – Hydrologic Cycle Condensation Results from water vapor cooling Forms clouds Precipitation Drops in clouds become to heavy to remain airborne Falls as rain, snow, sleet, hail Results in redistribution of water supply

10. Water Sources – Hydrologic Cycle Groundwater Infiltration The movement of water through the soil Some moves upward due to capillary action Percolation The downward movement of water in the soil Downward below root zone Reaches water table (saturated area)

11. Water Sources – Hydrologic Cycle Surface runoff When soil can hold no more water it is saturated Excess precipitation flows downhill Eventually reaches rivers, lakes and the ocean Cycle continues

12. Water Sources – Hydrologic Cycle Aquifers Unconfined aquifers Surface of saturated zone free to rise and fall Confined aquifers Also called an artesian aquifer A permeable layer confined by an upper and lower layer Results is the water is under pressure Well water rises, not necessarily to the surface

13. Water Sources – Hydrologic Cycle

14. Water Sources – Hydrologic Cycle Aquifer materials A variety of materials Sand – small or large grains Limestone or fractured rock Important Porosity - How much the aquifer can hold Permeability – How well the water can flow

15. Water Sources – Hydrologic Cycle Impurities In precipitation mostly effects surface water Dissolves gases from the atmosphere Picks up dust and other solids Generally soft, low in total solids, low to neutral pH Can be corrosive Groundwater Effected by materials picked up in run off Effected by materials in the water table

16. Water Sources – Surface Water Surface water sources Primarily lakes and rivers Relied on by large urban areas in most cases Canals, aqueducts and pipelines Bring water in from distant sources

17. Water Sources - Groundwater Groundwater sources Springs Rarely used by utilities Infiltration galleries Collect water from surface sources Wells Drilled into water table Serves 48% of general population Servers 95% of rural population

18. Water Sources - Groundwater Parts of a well Sanitary seal Air vent Well casing Grout Screen Discharge pipe Pump Gravel packing

20. Water Sources - Groundwater Well terms Static water level Pumping level Drawdown Cone of depression Zone of influence Residual drawdown Well yield Specific capacity

21. Water Sources - Groundwater Static water level Water level when no water level is being withdrawn Measured from ground surface to water level Monitors changes in water table Pumping water level Water level when pump is on Pump must be below this level Drawdown Level between static level and pumping level

22. Water Sources - Groundwater Cone of depression In unconfined aquifer, water flows from all directions Free water surface takes the shape of a cone Zone of influence Zone affected by drawdown Distance depends on ground porosity Low porosity equals large zone of influence

23. Water Sources - Groundwater Residual drawdown After pumping, water rises in the well If rise does not reach original level Well yield What the well can produce over a long period of time Measured in gpm or gphr If pumping exceeds recharge, safe yield will be reduced Pump will be damaged if sucks air To correct problem, well can be left to “rest”

24. Water Sources - Groundwater Specific yield (Specific capacity) Specific yieldgpm/ft = Well yieldgpm÷ Drawdownfeet Calculation used to monitor well operation Should be done frequently Indicates Pump wear Screen plugging Other problems

25. Water Sources - Groundwater Well location Where maximum yield possible is obtained Where can be protected from contamination How toselect location Existing data Likely locations Exploration

26. Water Sources - Groundwater Existing data State and Federal geological agencies Likely water quality Hardness, iron and manganese, sulfur, nitrates, etc Contamination possibilities Owners of surrounding wells Local well drillers

27. Water Snmources - Groundwater Likely locations More likely under valleys than on hills Material washed down from mountains – likely aquifers Presence of surface water Streams Springs Seeps Swamps Lakes

28. Water Sources - Groundwater Exploration Do underground exploration before drilling a full sized well Tests Seismic and resistivity tests Shock waves from dynamite The lower the ground’s electrical resistivity, the great the probability of water presence Test wells Earth samples taken Checked electrically or with gamma rays

29. Water Sources - Groundwater Exploration Computer modeling Measures complex stresses and effect on aquifer Calculates withdrawal and recharge rates Location of additional wells Possible contamination

30. Water Sources - Groundwater Sources of contamination Landfills Hazardous-waste sites Liquid waste storage Septic tanks, leachfields Deep well injection Agriculture Sludge application Infiltration from runoff Deicing activities Radioactive waste Abandoned wells

31. Water Sources - Groundwater Types of wells Dug wells Bored wells Driven wells Jetted wells Drilled

32. Water Sources - Groundwater Dug wells Can supply large amounts of water from shallow source Dug with Pick and shovel, Clamshell, Backhoes May be lined with concrete liners called curbs Public utility dug wells may be 8 to 30 feet in diameter 20 to 40 feet deep Vulnerable to contamination

33. Water Sources - Groundwater Bored wells Can be constructed quickly Soil must be suitable Limited to 3 feet in diamter and 25 to 60 feet deep Casing is forced down as hole is bored Cement grout surrounds the casing to block surface water

34. Water Sources - Groundwater Driven wells Simple to install Water must be neat the surface No rock layers or boulders in the way The point has a steel tip Diameters from 1 ¼ to 4 inches Maximum depth is30 to 40 feet For suction pump, static water level of at least 15 feet

35. Water Sources - Groundwater Jetted Well Soil must be appropriate – not hardpan, boulders Water is pumped down to the point Well screen on smaller diameter pipe is then placed in well Outer casing is withdrawn

36. Water Sources - Groundwater Drilled well Cable tool method Rotary hydraulic method Reverse-circulation rotary method California method Rotary air metho Down-the-hole hammer method

37. Water Sources - Groundwater Cable tool method Percussion drilling – wells of all sizes and depth Clublike chisel is driven into the earth Every 3 to 6 feet, a bailer is used to clean out hole Casing is used as necessary Operator adjusts tool blows for soil conditions At desired depth, a screen is lowered and pump installed

38. Water Sources - Groundwater Rotary hydraulic method Well is drilled with rapid rotation of a bit Drill pipe is hollow Fluid is pumped down – carries borings to surface Clay may be added to liquid to adhere to hole sides Reverse-circulation method As above, fluid circulates in the opposite direction Fluid returns to surface through drill pipe

39. Water Sources - Groundwater California method (stovepipe method) Used in unconsolidated material Similar to cable tool method but uses a special bucket When bit is dropped, bucket is filled with cuttings Steel casing forced down as well is deepens Rotary hammer method Similar to rotary hydraulic method Air is used instead of water Suitable only for drilling in consolidated rock Large drill rigs usually equipped to do both

40. Water Sources - Groundwater Down-the-hole hammer method Uses a pneumatic hammer Air also cleans away cutting from the bit For most rock, this is the fastest way to drill

41. Water Sources - Groundwater Special types of wells Radial wells Gravel-wall wells Bedrock wells

42. Water Sources - Groundwater Radial wells Commonly used near lakes or rivers Consists of central well with horizontal screened wells projecting outward from the bottom Central well serves as water collector Central cassion is generally 15 to 20 feet in diameter Each horizontal well is constructed with a gate valve Superstructure protects the well Bedrock well Well is drilled into bedrock – water flows through fractures

43. Water Sources - Groundwater Well construction procedures Well components Well casing Steel, iron, fiberglass, plastic Some have drive shoe on lower end Rotary drilled well casing installed after drilling

44. Water Sources - Groundwater Gravel-wall well or gravel packed well Best in fine grain material with uniform size Built with large casing with smaller casing with well screen Area around screen is filled with gravel Outer casing is withdrawn There are variations on the above

45. Water Sources - Groundwater Well components Well screens Used in unconsolidated formations Proper size: Minimum resistance Prevents sand from entering well Openings between 0.1 and 0.3 feet Must be sized to allow for buildup of headloss Plastic, mild steel, bronze, stainless steel

46. Water Sources - Groundwater Well components Grouting Seals out water to prevent surface pollution Seal out water from poor quality strata Protects casing against corrosion Restrains unstable soil and rock formations Annular space is filled Hole larger than casing when corrosion likely for 2’” grout

47. Water Sources - Groundwater Well development High rate pumping Surging Increased-rate pumping and surging Use of explosives High velocity jetting Chemical agents Pressure acidizing Hydraulic fracturing

48. Water Sources - Groundwater High rate pumping Where no screen is used – flushes out bore and aquifer Surging Employs a plunger or surge block Also achieved by using compressed air Increased rate pumping Develops wells in unconsolidated limestone Pumping rates increased in steps

49. Water Sources - Groundwater Use of explosives May be used to fracture massive rock formations Might be used to clear material that is plugging bore face Light charge used to agitate materials surrounding bore High velocity jetting Uses clean water under high pressure Breaks up compacted materials Wells is pumped in the meantime

50. Water Sources - Groundwater Chemical agents Chemicals frequently enhance some development methods Used with hexametaphospahtes to improve jetting May also be used where to disperse iron or carbonate Pressure acidizing May be used when good isolation from overlying formations to increase well productivity Hydraulic fracturing Fluid under pressure to open strata separations Gelling agents and sand added to hold fractures open

51. Water Sources - Groundwater Pumping tests To confirm that well produces water at design capacity Typically: 24 hours for confined aquifer 72 hours for unconfined aquifer Pumping rate is held constant Drawdown is measured frequently

52. Water Sources - Groundwater Sanitary considerations For shallow wells, surround with: 50 feet radius of clay Layer 2 feet deep Grout used to fill in annular space Disinfection Extended pumping removes most With 50 mg/L of chlorine with surging HTH included with gravel in gravel packed well

53. Water Sources - Groundwater Aquifer evaluation Observations wells located on map Routine measure of drawdown in observation wells Steel tape measure Air bubbler tube Electronic sensors Performance evaluated by: Drawdown method Recovery method Specific capacity method

54. Water Sources - Groundwater Well operation and maintenance Important base line data Static water level Pumping water level Drawdown Well production Well yield Time required for recovery after pumping Specific capacity

55. Water Sources - Groundwater Well abandonment and sealing Goal is restoration of geologic and hydrologic conditions To prevent physical hazard To prevent groundwater contamination To conserve the aquifer To avoid mixing water from different aquifers Work is best done by company who constructed the well

56. Water Sources - Groundwater Summary Wells often supply water to smaller communities Water quality generally consistent Minerals can be a problem Droughts may not effect as much as surface sources Proper maintenance and record keeping are important

57. Water Sources – Surface Water Surface water Primary source for larger communities and cities Cities have grown up around sources Great lakes Major rivers When groundwater insufficient, surface water from a distance carried to cities with aqueducts, pipelines

58. Water Sources – Surface Water Surface runoff Rain Runs off quickly toward streams etc. Snow Form of water storage Extremely important for western US and Canada Groundwater Springs and seeps Many streams would dry up without these

59. Water Sources – Surface Water Influences on runoff Rainfall Intensity and duration Soil Composition and moisture Ground slope Vegetation cover Human influences

60. Water Sources – Surface Water Watercourses Natural Brooks, streams, creeks, rivers Perennial streams Run year round Ephemeral streams Flow occasionally, brief existence Intermittent streams May run for weeks or months at a time Dry at some times

61. Water Sources – Surface Water Constructed watercourses Ditches, channels, canals, aqueducts etc. Used to divert water from one watershed to another May be used to prevent ponding from impeding growth Other uses Potable water Shipping, boat access Irrigation Water Bodies – Lakes, ponds and reservoirs

62. Water Sources – Surface Water Considerations for public use Quantity of water available (allow for growth) Required amount must be available Summer usually greatest use Safe yield Amount used during lowest flow Source Impoundment Watershed Rain or snow fall

63. Water Sources – Surface Water Considerations Water quality Almost any water can be made potable Expense considerations Political and legal issues Whose water is it? Supply and demand Salt water

64. Water Sources – Surface Water Considerations Water quality continued Temperature Taste, odor, color Algae Turbidity Microbiological contamination Chemical/radiological contamination

65. Water Sources – Surface Water Water storage Natural storage Impoundments Dams Utility is responsible for maintenance Failure Water loss Downstream destruction Maintenance record keeping important

66. Water Sources – Surface Water

67. Water Sources – Surface Water Groundwater recharge Create basins to provide recharge aquifers Injecting water into aquifer Must equal drinking water standards Turbidity an clog injection area EPA making it difficult to create new impoundments

68. Water Sources – Surface Water Surface intakes Spillway Disadvantages Warm water Ice in winter Floating debris Varying water levels

70. Water Sources – Surface Water Submerged intakes Best water usually at some depth Do not obstruct surface activity Floating debris not a problem Raised off of the bottom – prevents intake of silt/sand Typically water is pumped to treatment plant

71. Water Sources – Surface Water Operating Problems 1. Stream contamination Spills from barges and ships Spills from industrial installations Fertilizer Broken pipe lines Swamps after heavy rain

72. Water Sources – Surface Water Operating Problems 2. Lake Contamination Vulnerable to human and natural contamination Nitrates from farmland Algae growth, aquatic weeds Organisms – zebra and quagga mussels Lake straification

74. Water Sources – Surface Water Operating Problems 3. Icing Rapid cooling to freezing – frazil ice Small, disc shaped crystals Can plug intake Favorable conditions Clear sky at night Air temperature less than 19.4 degrees Day time temperature less than 32.4 degrees Winds greater than 10 mph

75. Water Sources – Surface Water Operating problems – icing continued Overcoming frazil ice problems Backflush with: Settled water Air Steam Switch intakes 4. Multiple intakes for slow flow Use of non-ferrous intake materials

76. Water Sources – Surface Water Operational problems 5. Evaporation Large surface can lose 6 to 8 feet to evaporation Cover with plastic or other material 6. Seepage Through bottom and sides Line reservoir

77. Water Sources – Surface Water Operational Problems 7. Siltation Streams carry sediment Serious problem for dams Cannot be prevented but can be limited Good farming procedures Controls on logging, road building Artificial wetlands Correction Dredging New source

78. Water Sources – Surface Water Emergencies and alternative sources Supply to public – continuous and uninterrupted Loss of pressure = contamination Lack of water for sanitation = spread of disease Emergency plans are important Below is discussion of possible situations and solutions

79. Water Sources – Surface Water Use and conservation of water Water, our most important natural resource Use has declined since 1980 Less used by agriculture, industry, power companies More is used by public water suppliers Domestic use about 105 gallons per day per capita Fire use Small across the country Maybe largest flow met by any given utility

80. Water Sources – Surface Water Causes of source disruption Natural disasters Earthquakes Storms Landslides Vandalism Spills Leaks Contamination Equipment failure

81. Water Sources – Surface Water Source contamination Chemical spills Some short term, some longer term effects Most chemical contamination can be dealt with Carbon adsorption

82. Water Sources – Surface Water Loss of water source Short term Conservation, rationing Use tank trucks Bottled water Water from neighboring system

83. Water Sources – Surface Water Long term options Drill new wells Construct new surface water sources Clean up contamination Connect to near-by town Impose permanent conservation requirements Reuse wastewater for non-potable uses Dual potable- nonpotable system New reservoir Aquifer recharge

84. Water Sources – Surface Water Evaluate the options Required procedures to implement option Is technology available How much water can option provide Can it meet systems total needs Can it be expanded to meet future needs What equipment and supplies are needed

85. Water Sources – Surface Water Reliability How reliable is option Does it require special operation and maintenance skills Political considerations What administrative procedures are needed Is property ownership a problem Will option be accepted by public

86. Water Sources – Surface Water Cost considerations What is initial investment What will be operating costs Who will pay for: Design Construction Operation

87. Water Sources – Surface Water Alternative water sources Surface water Two or more intakes at different locations Intakes in more than one source Construct wells for back up Groundwater Provide extra wells Locate wells in different aquifers Provide emergency source water supply All systems tie in with other systems

88. Water Sources – Surface Water Use and conservation of water Variations in water use Time of day and day of the week Climate and season of the year Type of community System water pressure Presence or absence of meters Quality of water

89. Water Sources – Surface Water Time and day of week Rapid rise early in the morning Significant rise early evening Industries may not operate on weekends Monday might be “wash day”

90. Water Sources – Surface Water Climate and season Most places higher in summer Some air conditioners use water Lawn and garden watering, bathing Usually lower in winter unless water is run to avoid freezing

91. Water Sources – Surface Water Type of community Industrial communities use can be higher than average Type of housing Individuals homes use more due to lawns and gardens Economically depressed areas generally use less

92. Water Sources – Surface Water Water pressure Normal pressure – 25 to 50 psig Increase of 25 psi to 45 psi = maybe 30% increase in use Metering Unmetered customers use 25% more than average Let hoses run Let faucets run Ignore leaks

93. Water Sources – Surface Water Sewers Customers with sewer connections tend to use 50 to 100% more water than those with septic systems Condition of the Distribution System Leaks result loss of revenu Poor condition results in: Taste and odor problems Reduced use and customer support for utility

94. Water Sources – Surface Water Conservation Gradual acceptance by public of need to conserve Efforts most effective in areas on minimal supply Benefits Reduced demand on source Energy savings Reduction in wastewater flow Reduced costs Protection of environment

95. Water Sources – Surface Water Drawbacks to conservation Loss of revenue Possible delay in developing new source Possible stimulation of water service growth Difficulty in dealing with drought conditions

96. Water Sources – Surface Water Loss of revenue Some offsetting expenses - power, chemicals May require increased rates Financial planning necessary before program starts In case of drought, hard to raise rates on short notice Delay in developing new sources If conservation successful, lack of public support for new source Delay can increase cost of new source development

97. Water Sources – Surface Water Stimulation of system growth More water available can attract more users Can be a system until new sources developed Drought conditions Drought after conservation is hard to explain asking for even less use Emphasizes need for good planning Utility must plan for future use

98. Water Sources – Surface Water Supply management techniques Careful management of all resources Analysis of water use data Complete source and customer metering Reduction of unaccounted for water

99. Water Sources – Surface Water Demand management techniques Public education Distribution of water-saving devices Management of water use demand Modification of rate structure Promotion of low water use agriculture and gardening Promotion of conservation by industry and business

100. Water Sources – Surface Water Drought conditions management Response Conservation Additional supply Emergency plan in place Identify additional sources ahead of time In extreme cases, fines for misuse of water

101. Water Sources – Surface Water Allocation of Water rights: Riparian Doctrine Appropriation Doctrine Most eastern states have a combination of the two Western and dry states tend to use Appropriation Doctrine

102. Water Sources – Surface Water Riparian Doctrine Common law doctrine based on civil cases Rule of “reasonable sharing” by abutting land owners Sharing rather than a right to a specific amount of water Uses not allocated a specific amount Use cannot interfere with others use Drought conditions Length of ownership or previous use is not a basis for use under these conditions

103. Water Sources – Surface Water Greater water use has resulted in: More frequent conflicts especially during droughts Increasing number of state statutes Gradual move toward Appropriation Doctrine

104. Water Sources – Surface Water Appropriation Doctrine “First in time, first in right” Water for irrigation greatest use in west Most laws relate to this type of use Two basic principals Priority use Beneficial use

105. Water Sources – Surface Water Priority use When less water than demand, who has used the longest No shared suffering Beneficial use Opposite of Riparian Rights – Land ownership not a factor User must prove used is beneficial Non-use for period of time can lead to loss of right This type of use tends to be settled in courts

106. Water Sources – Surface Water Legal complications Land boundries are clear, water use is not Water rights are highly independent and relative Many variables to consider Use may have to be adjusted Drought conditions Seasonal use for crops Nature of the source

107. Water Sources – Surface Water Rights for the use of Groundwater Absolute right Reasonable use Correlative rights Appriation-Permit systems

108. Water Sources – Surface Water Absolute ownership Owner of the land owns what is under it For all practical purposes = law of capture Water can be used for owner’s purpose or sold No liability if dries up neighbor’s well

109. Water Sources – Surface Water Reasonable use Interference with neighbor only ok if use is reasonable Owner is liable if use harms others Off site use is considered unreasonable it if interferes with others use of the water

110. Water Sources – Surface Water Correlative rights

111. Water Sources – Surface Water Appropriation-Permit systems Basically a permit system Most important issue is Rule of Priority Based on who has use the water the longest Adjustments to use not so necessary as with surface water Main control is limiting pumping

112. Water Sources – Surface Water Summary The evolution of water rights is more advanced in the western states than if the east. Control of water sources remains in under the control of the states.

113. Principles of Source Protection Surface and groundwater in watershed area to be protected Some utilities hire a consultant – work closely with him Federal funding may be available Organize a watershed management team Watershed delineation Potential and existing threats to water quality Set goals Control stategies Implement a source protection plan

114. Principles of Source Protection Ten steps to preparing plan: Organize community team Delineate watershed Review zoning Determine critical areas Inventory potential treats Prioritize potential threats Establish goals Prepare Source Protection Plan Reach out and educate Implement plan

115. Principles of Source Protection Community planning team Good when financial resources are limited Involves community people and their expertise Begins to educate the public to the need for source protection Public education may be most important part of plan Team might be: Municipal officials Public organizations Appropriate agency staff Farmers, developers, residents, business leaders

116. Principles of Source Protection Delineate your watershed Some states have done this with GIS Topo maps may be enough for small systems Use large scale map i.e. 1:5,000 Watershed may include other towns Physically go out an inspect boundary lines Some towns put up signs indicating watershed area

117. Principles of Source Protection Review zoning Get information from code enforcement officer Evaluate restrictions already in place Consider: Permitted land uses Conditional land uses Town’s long range plan for directing growth Existing performance standards

118. Principles of Source Protection Determine critical areas Identify sensitive areas – personal tour important Steep slopes Unvegetated or disturbed areas Various soil conditions Forest areas Streams, brooks, ponds and lakes Wetlands Review USGS history of precipitation and stream flow recordsL=

119. Principles of Source Protection Inventory potential threats Important to identify pollutants and their sources On a 1:5,000 map mark out areas Use zoning maps and town master plans Double check information from state agencies to be sure information is current Update information over time

120. Principles of Source Protection For potential pollution sources: Permitted discharges Solid waste facilities Residential development Industrial/commercial development Agricultural activities Water demand Use lists of relative risk from various uses

121. Principles of Source Protection Prioritize potential threats Use list of potential sources of pollution Consider Amounts of pollutants Toxicity Water quality impacts Cooperation needed from abutting towns Review periodically

122. Principles of Source Protection Source protection plan should consist of: Control measures Education and outreach strategies Implementation strategy Control measures may be regulatory or non-regulatory Regulatory – bylaws, ordinances Non-regulatory – buffer zones, detention basins, erosion controls

123. Principles of Source Protection Reach out and educate Non-regulatory measures rely on education and outreach Regulatory measures rely on support from public and town officials Use of “Best Management Practices” good guideline

124. Principles of Source Protection Implement the plan Need PUBLIC SUPPORT Establish individual who will enforce the plan Pick people with proper expertise (spetic systems, zoning) Consider a “Water Supply Advisor Committee” Review projects that threaten watersupply Work closely with the Planning Board Keep program updated

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