Lecture A2 - Water Feature Materials Notes

LECTURE A2: Water Feature Materials My Notes - LHAP 302A Water and Light LEARNING OUTCOMES Describe selected kinds of ponds Compare selected pond liners Describe selected features employing moving water Outline the purpose and selection of equipment used in water feature systems KINDS OF PONDS THE BIG IDEA: Every water feature must be watertight and deep enough to support aquatic life. Features can be built from a broad range of materials in any shape or size. General pond structure includes: A defined edge Shelves or ledges for marginal plants A deep area for water lilies Optionally, a biofalls and skimming unit 1. EARTH PONDS (Earth Features) For sites with good clay subsoil and natural water feed. If space allows, can be used for recreation: swimming, canoeing, raising trout in summer, skating in winter. How They Work No commercial liner. Rely on natural water-holding capabilities of clay subsoil. The clay is puddled to create a natural lining. What Is Puddling? Compacting clay to completely force out the air, creating a densely packed watertight barrier. Historically done by herding sheep over clay; now vibrating plate tamper is used. Key Requirements Drainage patterns must be respected A steady water source is crucial 4 cm layer of topsoil over puddled clay to start plant and animal life KEY POINT: Puddled earth ponds require: clay subsoil + steady water source + proper drainage. TEST TIP: Puddled earth pond = built on clay, suitable for large-scale, needs steady water = ALL OF THE ABOVE 2. FLEXIBLE LINER PONDS MOST POPULAR material for water feature construction. Advantages Conforms to virtually any shape - greatest design flexibility Easiest pond material to install Minor edge variations easily corrected after installation Edge finished with: pebble beach, indigenous rock, complementary plants Easy and inexpensive to repair (challenge = finding the hole) Most economical construction method Cautions Extra vigilance during installation Soil walls can slump - liner conforms to the problem Sharp objects and stones can puncture FLEXIBLE LINER MATERIALS - The Three Types A. BUTYL RUBBER Synthetic rubber. Found in tire inner tubes, caulks, sealants, cling wrap, chewing gum. KEY ADVANTAGE: Can be WELDED (box-welding) to create virtually any 3D shape. Only liner type that can be welded. B. PVC (Polyvinyl Chloride) Made from durable fish-grade PVC. Should contain UV stabilizers. WARNING: Even with UV protection, PVC deteriorates within 2-3 YEARS in direct sunlight. Cover liner above water level to extend life. C. EPDM (Ethylene Propylene Diene Monomer) Most popular choice among pond builders. Flat sheets - hide folds/pleats with plants and rocks Cannot be welded - seams taped with butyl tape (not always successful) Best: buy single piece large enough for entire pond = no seams Even better: design pond to fit available liner sizes Flexible to -70C even years after installation Limited 20-year warranty CRITICAL: Do NOT use roofing EPDM - must be "fish safe" pond liners! KEY POINT: EPDM = longest life span in prairie climate, flexible to -70C, most popular. 3. PREFORMED (MOULDED) PONDS Good for small urban landscapes. Durable, repairable. Dig in a few hours. Material Life Expectancy Prairie Suitability Polyethylene 20 years Stands up better Fiberglass 15-20 years More brittle in freeze/thaw WARNING: Preformed ponds look large in store but SHRINK once installed! 4. CONCRETE PONDS Rapidly declining in use. Requires professional contractor (expensive) Difficult to create natural shapes - formal only Very rigid - will not flex Prone to freeze/thaw cracking Once cracked, hard to repair Must be cured (filled/drained repeatedly) if adding fish Lime creates additional work during curing process KEY POINT: Concrete is NOT ideal for prairies. Summary of Pond Characteristics (Table 1) Type Cost Durability Ease of Install Design Flex Repair Other LINERS Polyethylene Low Poor Easy Good Difficult Short life span PVC Low-Med Fair-Good Easy Good If not brittle Punctured; holes hard to find Butyl/EPDM Med-High High Easy Excellent Possible always Holes hard to find PREFORMED High Fair Can be difficult Limited Possible Expensive for water qty CONCRETE Very High Poor (freeze/thaw) Need professional Good Hard to keep tight Lime = extra work FEATURES WITH MOVING WATER Moving water adds aesthetic + practical benefits. Helps AERATE the water. KEY RULE: Fountains = FORMAL only. Not found in nature. 1. Waterfalls and Streams Must prevent spillage/leaking and reduce evaporation. Moving water = high evaporation rates. Water lilies need still water - adjust volume or use separate basin Preformed units: engineered, durable, but expensive and artificial-looking Flexible liner (butyl/EPDM): best for informal, requires careful planning Design stream as gradual meanders connecting ponds, not starting atop a berm 2. Pondless Waterfalls Re-circulates water without a pond. Sight + sound without maintenance/liability. KEY POINT: Great for space-limited or safety-conscious installations. 3. Bubbling Rocks Fast and easy to install. Natural stone or cored stone. Basalt columns very popular. 4. Fountains Formal settings only. Shapes: water bells, daisies, foaming jets, tulips. Small jets: lost in large landscapes, tend to clog Geyser jets: less clogging, but wind-sensitive Ornamental: frogs, rabbits, lionheads, gargoyles, sculptures EQUIPMENT FOR WATER FEATURES A pump is the HEART of a water feature. Some pumps can be left year-round without freezing damage. Koi vs. Natural Ponds: If planning Koi, a filtration system is a NECESSITY. Without Koi, use skimmers and biofalls for filtration. 1. PUMPS Modern submersible pumps. Some can freeze solid without damage. Performance: GPH and maximum lift (head) - inverse relationship 2x RULE: move at least twice the pond volume per hour Buy BIGGER than needed - add diverter or restrict with ball valve CRITICAL: NEVER restrict pump INTAKE. Only restrict OUTPUT with ball valve. Required: 110-volt GFCI outlet. 2. FILTRATION SYSTEMS A. Mechanical Filters Trap debris through filtering agent. Effective but HIGH maintenance. B. Biological Filters (Skimmers + Biofalls) Modern, preferred system: Pond skimmer: collects debris, houses pump, has filter media + beneficial bacteria Beneficial bacteria: consume nutrients, more efficient than algae Biofalls: second filter media pass with more bacteria. Complete filtration. Biofalls: easy to maintain, clean ONCE per year, easy to hide QUIZ ALERT: "Skimmers and Biofalls are MECHANICAL filters" = FALSE! They are BIOLOGICAL filters. 3. HEATERS Floating heater keeps small area ice-free. Thermostat activates near freezing. KEY POINT: Purpose = NOT to warm water. Keeps ice-free spot for CO2/O2 gas exchange so overwintering fish can survive. QUICK RECALL Q&A Question Answer Most popular construction material? Flexible liners Preformed ponds made from? Polyethylene or fiberglass Is concrete ideal for prairies? NO - freeze/thaw, rigid, expensive Main waterfall/stream challenge? Water loss from evaporation Are bubbling rocks easy? YES - fast and relatively easy Can pumps freeze solid safely? YES - some modern submersible Skimmers/biofalls = mechanical? NO - biological filters What is puddling? Compacting clay = watertight barrier Which liner can be welded? BUTYL RUBBER (box-welding) EPDM key advantage? Flexible to -70C, 20-yr warranty Pump output minimum? At least 2x pond volume/hour Why never restrict intake? Damages pump - restrict output only Pump outlet needed? 110-volt GFCI Most UV-susceptible liner? PVC - 2-3 years in sun Why floating heater? Ice-free area for CO2/O2 exchange Where do fountains belong? FORMAL features ONLY How often clean biofalls? Once per year EPDM warranty? 20 years (limited) Better preformed for prairie? Polyethylene Puddled earth pond = ? Clay + large-scale + steady water QUIZ PREP - Common Misconceptions (TRUE/FALSE) Statement Answer Explanation Flexible liners are most popular TRUE Any shape, easiest, economical Preformed from polyethylene/fiberglass TRUE Both available Concrete is ideal for prairies FALSE Freeze/thaw cracks, rigid Waterfall challenge = evaporation TRUE Moving water = high loss Bubbling rocks are fast and easy TRUE Various sizes available Some pumps freeze solid safely TRUE Modern submersible pumps Skimmers/biofalls = mechanical FALSE BIOLOGICAL filters EPDM can be welded FALSE Only BUTYL welds; EPDM uses tape PVC lasts forever with UV stabilizers FALSE 2-3 years in sun Fountains suit informal features FALSE FORMAL only Restrict pump intake for less flow FALSE NEVER restrict intake Floating heater warms the water FALSE Gas exchange only CRITICAL NUMBERS TO REMEMBER Value What It Means 2x volume/hour Minimum pump output -70C EPDM stays flexible 2-3 years PVC in direct sunlight 20 years EPDM warranty 20 years Polyethylene preformed life 15-20 years Fiberglass preformed life 4 cm Topsoil over puddled clay 1x/year Biofalls cleaning frequency 110 volts GFCI outlet for pump LECTURE SUMMARY The Four Pond Types Earth ponds - rural sites with clay + natural water source Flexible liner ponds - most popular; butyl, PVC, or EPDM Preformed ponds - small urban; polyethylene preferred Concrete ponds - declining; rigid, expensive, cracks Moving Water Features Waterfalls/streams - sight, sound, aeration; watch evaporation Pondless waterfalls - no pond maintenance/liability Bubbling rocks - fast, easy, great impact Fountains - formal ONLY; interchangeable jets Essential Equipment Pumps - buy bigger, 2x rule, never restrict intake Filtration - mechanical vs biological (skimmers + biofalls) Heaters - floating, CO2/O2 exchange for overwintering fish Key Takeaways Flexible liners = most popular, most economical EPDM = best for prairies (-70C, 20-yr warranty) Butyl = only liner that can be welded Polyethylene = most susceptible to punctures/UV; PVC degrades fastest in direct sun Concrete NOT ideal for prairies Skimmers + biofalls = biological (NOT mechanical) Pumps: buy bigger, 2x rule, never restrict intake Heaters = gas exchange, not warming water WHAT'S NEXT: Module A3 - Water Feature Construction Material | Life Expectancy | Prairie Suitability Polyethylene | 20 years | Stands up better Fiberglass | 15-20 years | More brittle in freeze/thaw Type | Cost | Durability | Ease of Install | Design Flex | Repair | Other LINERS | | | | | | Polyethylene | Low | Poor | Easy | Good | Difficult | Short life span PVC | Low-Med | Fair-Good | Easy | Good | If not brittle | Punctured; holes hard to find Butyl/EPDM | Med-High | High | Easy | Excellent | Possible always | Holes hard to find PREFORMED | | | | | | | High | Fair | Can be difficult | Limited | Possible | Expensive for water qty CONCRETE | | | | | | | Very High | Poor (freeze/thaw) | Need professional | Good | Hard to keep tight | Lime = extra work Question | Answer Most popular construction material? | Flexible liners Preformed ponds made from? | Polyethylene or fiberglass Is concrete ideal for prairies? | NO - freeze/thaw, rigid, expensive Main waterfall/stream challenge? | Water loss from evaporation Are bubbling rocks easy? | YES - fast and relatively easy Can pumps freeze solid safely? | YES - some modern submersible Skimmers/biofalls = mechanical? | NO - biological filters What is puddling? | Compacting clay = watertight barrier Which liner can be welded? | BUTYL RUBBER (box-welding) EPDM key advantage? | Flexible to -70C, 20-yr warranty Pump output minimum? | At least 2x pond volume/hour Why never restrict intake? | Damages pump - restrict output only Pump outlet needed? | 110-volt GFCI Most UV-susceptible liner? | PVC - 2-3 years in sun Why floating heater? | Ice-free area for CO2/O2 exchange Where do fountains belong? | FORMAL features ONLY How often clean biofalls? | Once per year EPDM warranty? | 20 years (limited) Better preformed for prairie? | Polyethylene Puddled earth pond = ? | Clay + large-scale + steady water Statement | Answer | Explanation Flexible liners are most popular | TRUE | Any shape, easiest, economical Preformed from polyethylene/fiberglass | TRUE | Both available Concrete is ideal for prairies | FALSE | Freeze/thaw cracks, rigid Waterfall challenge = evaporation | TRUE | Moving water = high loss Bubbling rocks are fast and easy | TRUE | Various sizes available Some pumps freeze solid safely | TRUE | Modern submersible pumps Skimmers/biofalls = mechanical | FALSE | BIOLOGICAL filters EPDM can be welded | FALSE | Only BUTYL welds; EPDM uses tape PVC lasts forever with UV stabilizers | FALSE | 2-3 years in sun Fountains suit informal features | FALSE | FORMAL only Restrict pump intake for less flow | FALSE | NEVER restrict intake Floating heater warms the water | FALSE | Gas exchange only Value | What It Means 2x volume/hour | Minimum pump output -70C | EPDM stays flexible 2-3 years | PVC in direct sunlight 20 years | EPDM warranty 20 years | Polyethylene preformed life 15-20 years | Fiberglass preformed life 4 cm | Topsoil over puddled clay 1x/year | Biofalls cleaning frequency 110 volts | GFCI outlet for pump