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Water Works. By: Tabitha Isham Mark Hartman Kim Bracher Kristine Newton. Agenda. Global, National, and Local Statistics Global Sanitation Problems Sewer and Wastewater Management Local Players and Roles Sustainability and Conservation Connections to our Education Wrap it up!.
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Water Works By: Tabitha Isham Mark Hartman Kim Bracher Kristine Newton
Agenda • Global, National, and Local Statistics • Global Sanitation Problems • Sewer and Wastewater Management • Local Players and Roles • Sustainability and Conservation • Connections to our Education • Wrap it up!
Global Outlook • Available Fresh Water • Of all water on earth, 97.5% is salt water • Of the remaining 2.5% of fresh water; • 70% is frozen in the polar icecaps. • 30% is mostly present as soil moisture or lies in underground aquifers. • Less than 1% of the world's fresh water (or about 0.007% of all water on earth) is accessible for direct human uses.
Global Issues • Approximately 60 to 70% of the rural population in the developing world have neither access to a safe and convenient source of water nor a satisfactory means of waste disposal. • Presently, 1.1 billion people lack access to improved water supply and 2.4 billion to improved sanitation. The number of people who are projected to lack access to improved water supply could increase to 2.3 billion by 2025.
A Little Perspective • The average American individual uses 100 to 176 gallons of water at home each day. • The average African family uses about 5 gallons of water each day.
Estimates of water use in the United States indicate that about 408 billion gallons per day (Bgal/d) were withdrawn for all uses during 2000. Fresh ground-water withdrawals (83.3 Bgal/d) during 2000 were 14% higher than in 1985. Fresh surface-water withdrawals for 2000 were 262 Bgal/d, varying less than 2 percent since 1985. National Outlook
Irrigation remained the largest use of freshwater in the United States and totaled 137 Bgal/d for 2000. Since 1950, irrigation has accounted for about 65% of total water withdrawals. Historically, more surface water than ground water has been used for irrigation. However, the percentage of total irrigation withdrawals from ground water has continued to increase, from 23 percent in 1950 to 42 percent in 2000. Cont.
1950 Public-supply withdrawals were 14 Bgal/d. 62% of the population in the US obtained drinking water from public suppliers. Surface water provided 74% of US drinking water. 2000 Public-supply withdrawals were more than 43 Bgal/d. 85% of the population in the US obtained drinking water from public suppliers. Surface water provided 63% of US drinking water. National Comparisons
Extensive withdrawals of ground water leads to land subsidence: http://water.usgs.gov/ogw/pubs/fs00165/Images/fig2.jpg
http://pangea.stanford.edu/courses/gp104/waterscape/users/pdempsey/chart.jpghttp://pangea.stanford.edu/courses/gp104/waterscape/users/pdempsey/chart.jpg
Lee County Water Consumption and Use • Lee County • Every person uses 175 Gallons of Water Per Day. • Twice the National Average • ½ Water Used For Irrigation of Landscapes and Golf Course. SFWMD 2007
Lee County Water Supply • Rainfall= 90% Of Water Supply • Transported through Watershed “Water Supply”
What is a septic system? • State of Florida refers to a septic system as an Onsite Sewage Treatment and Disposal System or OSTDS. • In 1997 the US Environmental Protection Agency publicly recognized “onsite systems… as potentially viable, low-cost, long-term, decentralized approaches to wastewater treatment if they are planned, designed, installed, operated, and maintained properly.” • Florida Department of Health’s Bureau of Onsite Sewage Programs • 850-245-4070 or www.doh.state.fl.us/environment/ostds/index.html.
How does a septic tank work? • Septic tanks are near the house, below ground, in the front yard. They are concrete and act as a holding chamber for all liquid and solid waste. • Once in the septic tank, solids sink to the bottom and the liquids drain into a series of perforated pipes about 2’ below the surface. • Liquids seep into the soil where microbes digest the organic material and plants are able to absorb the nutrients.
Continued…. • By this method, human waste is transformed into carbon dioxide, water and biomass of bacteria and plants. • This is why you may notice grass is greener, grows taller or trees planted nearby grow better!
Oh, then what? Out of sight out of mind? • NO, eventually the tank gets full. • Every 5+ years the homeowner will need to hire a contractor to come out and pump the septic tank. (the less paper you use and not flushing sanitary items will lengthen the time between pumping) • Where does it go then? The solids pumped out go to a treatment plant.
Sewer Pipes (city option) • When you have an area with many homes clustered together it becomes a better option to service them with a main sewer line. • Main sewer pipes run along the length of the road, with the individual home installing a lateral pipe to ‘plug into’ the main.
Sewer Line • The lateral pipe takes the waste to the main line. • Gravity moves the solid waste from the house through the sewers to a sewage treatment plant. • Pumping stations along the way ensure a steady flow. • At the treatment plant the wastewater undergoes several processes before it can be returned to the water cycle.
City of Cape Coral Sewer Mains • The first step in the construction process is to remove the existing road surface. • Next, the existing water table must be lowered to facilitate digging in the immediate area. A series of shallow well points will be installed and the water pumped to a nearby canal.
Continued… • Barriers will be constructed to minimize the sound produced by the pumps, which will oftentimes be running around the clock. • Gravity sewer lines and manholes are installed under the streets. They range in depth from 4 feet to almost 20 feet down. Since these lines are deeper, progress is slower and disruption is greater for sewer than for water and secondary water.
Process continued.. • Safety standards require sloping these trenches. Trench boxes will be used for the deeper excavations, but in many cases the entire width of the road will be dug up • The water and secondary water lines are then installed. These lines are much shallower and are installed in much narrower trenches along either side of the road.
Almost done! • In some cases, the driveways will need to be cut in order to install these shallow lines. A narrow trench will be made and a temporary gravel repair will be provided at the end of the workday • The final driveway repair will consist of removal and replacement of a minimum of 3 feet of driveway apron. Additional reinforcing steel will also be installed to beef up the corners.
Viola! Finished Product • This is a picture of final restoration completed on the North Loop project • For undeveloped lots, seeding and mulching are provided instead of sod.
The hook up after the lines are in, another homeowner expense. • After the actual construction of the utility lines is finished the post construction phase begins. This is a very important time for individual residents. Remember—the City lines stop at the right-of-way, therefore, owners are responsible for connecting their houses to the City’s line. Once our construction is complete, property owners will receive a notice that they should proceed with hooking up the City lines.
Permitting Required • The first step is applying to the City Customer Service Division for permits for water and wastewater hook-ups and septic tank abandonment.
Process ends with City and County Inspection • Once permits are obtained, property owners may have a licensed plumber make the water and wastewater connection and the required septic system abandonment. • Whencomplete, your new connections must be inspected by the City, and Lee County must inspect your septic tank.
Looks and Sounds Great! Why doesn’t every area with housing do this up front, no septic tank? • Well, its expensive. Without a certain number of homes to share the assessments cost the city cannot afford to do the construction. However, once the home is built and financing is secured, the city forces the assessment. • The Cape was broken down into areas, with each area waiting for a certain population before beginning the process. Some of the north cape is still not slated until 2017.
The benefits of Sewer main lines • “Flush toilets and sewers are generally the safest, most convenient, most easily maintained forms of provision in urban areas for homes, schools, workplaces, and public places. They provide public health advantages by reducing the risk of human contact with excreta and preventing groundwater contamination.”-- SOW
Something is better than nothing • Seeking to reach everyone with adequate provisions does not necessarily mean reaching everyone with the same form of provision. It is much better to have well-managed cheaper provisions in low-income areas than no provision at all---well-managed communal taps, for instance, rather than house connections. SOW • The text notes that in many poorer urban areas where facilities are badly needed there is no local agency to provide the needed design, implementation, management, and financing of such a project.
Low end options • A pit latrine may be an option for some areas where there people have to defecate in the open. It could be easily built and managed be a family without the aid of an external agency. • (what goes into the pit doesn’t necessarily stay in the pit. The excreta can leak into the ground contaminating the water supply, but this is still a better cleaner option than going on the side of the road without toilet paper)
Flush toilet connected to sewer or septic tank within each home, with piped water for washing “Improved” latrine (controls smell better) within each home Basic latrine Access to public toilet or latrine Open defecation $400-1500 $40-260 $10-50 12-40 $0 Different Sanitation Options and Costsbased on U.N. Development Program, Human Development Report 2006
Reclaimed Water, a great conservation tool • Up to 50 percent of a community's drinking water is used for irrigation. Much of this irrigation water could be replaced with reclaimed water. • Reclaimed water is a clear and odorless high-quality water source for industrial and irrigation needs.
Appropriate Uses • It can be used for: • Irrigation • Street-sweeping operations • Power generation • Decorative fountains • Fire protection (purple fire hydrants) • Dust control • Aquifer recharge • Cooling or makeup water for a variety of industrial processes • Natural system restoration
Inappropriate uses • it can’t be used for: • Body-contact recreation (including swimming pools) • Cooking or drinking • Irrigating vegetable and herb gardens (unless a drip or bubbler system is used)
The wastewater to reclaimed water process • Screens and other processes remove sand & debris • Sedimentation removes large solids • Microorganisms break down organic materials • Clarifiers remove microorganisms and remaining solids • Filtering makes water clear • Disinfection, usually with chlorine, kills the remaining microorganisms
Benefits of using reclaimed water • Costs less than drinking water • Reduces fertilizer use, as some nutrients like nitrogen and phosphorous remain • Reduces stress on drinking water supplies • Reduces disposal into waterways, which can help reduce nutrient loads in bays and rivers
1986 The reuse capacity of Florida's domestic wastewater treatment facilities was 362 million gallons per day (MGD). 2001 The reuse capacity of Florida’s domestic wastewater treatment facilities was 1,151 MGD. Growth of Reuse in Florida
Reclaimed water use in the District (for 2005) More than 45 percent (159 mgd) of wastewater in our area is reused. Six local power plants use reclaimed water as cooling water. Over 160 area golf courses irrigate with reclaimed water. Almost 9,000 acres of mostly citrus crops are irrigated with reclaimed water. About 78,000 residential customers in our area irrigate with reclaimed water. Statistics Reuse grant funding since 1987: $225 million Miles of reuse mains: 858 Capacity of funded projects: 219 mgd Daily use: 183 mgd Alternative water supply grant funding since 1996: $317 million Reclaimed water in use (2005)
Approximately 584 million gallons per day MGD of reclaimed water were reused for beneficial purposes in 2001. Top 12 Reuse counties in Florida (2001): Collier #1 with 89% of wastewater reused or 106.66 gallons/day/person Lee #7 with 88% of wastewater reused or 79.17 gallons/day/person Reuse Trends in Florida
Of the bottom 12 Reuse Counties in Florida: Miami-Dade is #1 with only 6% of their wastewater being reused. Broward is #5 with 5% reuse Miami-Dade and Broward Counties contain over 24% of Florida’s population and generate 33% of the state’s domestic wastewater. Yet they account for less than 4% of all reuse capacity in the state. Who is not on board with water reuse
Still Living Without the Basics in the 21st Century • Today only .64% of U.S. households lack complete plumbing facilities. • This is a monumental leap from 1950, when more than one-fourth of the nation, and more than half of all rural residents, lacked those facilities.
