What is a chamberpot?
- Bowl-shaped container with a handle, and often a lid that was used as a toilet by people in ancient Greece, ancient Rome, and other parts of the world where indoor plumbing did not exist.
When following proper etiquette if a man and woman are walking together on a sidewalk who should walk next to the curb: the man or the woman and why?
- Women would walk closer to the buildings in order to avoid being showered in sewage. This practice dates back to medieval London where it was customary for people to throw wastewater, including human waste, in the street even if they lived two or three floors up.
Where did the term S.H.I.T. come from?
- It stand for ship high or stow high in transit. When manure was transported below deck during the 16th and 17th centuries it would become wet due to moisture from ocean water. The result of wet manure was methane gas that when exposed to an open flame combust. To prevent ships from exploding, the manure was stored on the upper decks of the boat.
United States Water Laws
Federal Water Pollutions Control Act
- The Federal Water Pollution Control Act of 1948 authorized the surgeon general of the Public Health Service, in cooperation with other Federal, state, and local entities, to prepare comprehensive programs who’s focus included: eliminating or reducing the pollution of interstate waters and tributaries along with improving the sanitary condition of surface and underground waters.
- Due regard was given to improvements necessary to conserve waters for public water supplies, propagation of fish and aquatic life, recreational purposes, and agricultural and industrial uses when developing plans.
- The original statue also authorized the Federal Works Administrator to assist states, municipalities, and interstate agencies in constructing treatment plants to prevent discharges of inadequately treated sewage and other wastes into interstate waters or tributaries.
- Multiple amendments have been made to act, now known as the Clean Water Act.
Clean Water Act (CWA)
- This act firmly establishes federal regulation of the nation’s waters, and contains provisions designed to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.”
- The CWA is monitored by the Environmental Protection Agency (EPA).
- In 1972, the CWA was amended to require limits for determining which point sources are consistent with State water quality standards. Also, procedures for State issuance of water quality standards and the development of guidelines to identify and evaluate the extent of nonpoint pollution.
- Other amendments included: water quality inventory requirements, development of toxic and pretreatment effluent standards, and establishing the National Pollutant Discharge Elimination System (NPDES) which authorized the EPA to issue discharge permits.
“The following excerpt from Soils Influence on Onsite Wastewater Treatment by Brent Elliott (December 2013).”
Ancient Irrigation for Public and Agricultural Uses Background:
Throughout the course of history, the need for water sources has been one of highest priorities for civilizations. Without a reliable water source people would not be able to grow crops, bathe, drink, and perform other water dependent daily activities. Thus, humans realized quickly the importance of water and the need to have a constant quality available. To accomplish this task, many different ideas where conjured in hopes of building water supply sources. Whether large holding bins to capture rain water or simply moving next to a large water source such as a river, humans understood sustained life revolved around water. As years have passed, humans have learned to manipulate water sources and devise systems to control water use for applications such as agriculture.
The Ancient Egyptians set up their permanent civilizations along the Nile River. “The Nile receives its water from the tropical highlands of Africa. The river receives no tributaries at all for the last 1500 km of its course across the Sahara Desert to the Mediterranean. In Egypt, far from its sources of water, the Nile has no sudden flood-wave crests. The annual flood starts in June as snowmelt and summer rain flow down the river. It rises gently to its peak in late September and early October, then gently subsides by the end of December. “The Nile is one of the most predictable rivers in the world, and its ‘flood’ period averages more than a hundred days, rather than being very short-lived like those of other rivers” (UC Davis para 13). The Egyptians learned to use the predictability of the river to their advantage and planned crop planting rotations based on that knowledge. They built detention basins based on previous year’s crest heights to hold water for crops. The flow of the Nile River was fast enough to avoid accumulation of silts and salts in the crop lands which allowed the ground to remain fertile and usable each year as the flood subsided.
Another civilization that used available water for irrigation purposes for over 6000 years was Mesopotamia (current day Iraq and Iran). This civilization experienced floods just like Egypt, but these floods were less predictable and typically had more water for flooding an area in a smaller amount of time. To control the flood waters, “Mesopotamian engineers built very large weirs and diversion dams, to create reservoirs and to supply canals that carried water considerable distances across the flat countryside” (UC Davis para 28). Due to these engineered irrigation practices, Mesopotamia was able to harness the available water and help ensure annual crop production. Problems were encountered with their weirs and diversion dams due to the unpredictable flooding. Consequently, the crop land would be littered with silt and salts that inhibited the soils from growing crops for many years. Engineers tried to dredge the land in attempt to remove the excess sediment, but found the soil was still hindered. When other large human populations sprang up, they learned from the mistakes of the Egyptians and Mesopotamians. Instead of building large cities next to rivers known for flooding they would build structures to carry water directly to them. The Romans perfected this design with the aqueduct over 2000 years ago and remains are still visible today (Conceicao para 4). Water from the mountains was channeled down by gravity to fields, cities, and reservoirs. The system was designed to allow Romans to control the flow and amount of water running in the aqueducts at any given time. No longer was there a threat of flooding and loss of crops due to non-fertile soil.
Innovation has helped humans prosper, but at a cost. Over the course of history, humans have used water injudiciously without thoughts of consequences and future impacts. When people flush the toilet, wash their hands, take a shower, water the garden, and irrigate the corn field, they use water. These reasons and many others explain why the available freshwater in the world is quickly being depleted. Fresh water makes up only 2.5% of all the Earth’s available water. Of this 2.5%, 69% is locked up in glaciers and ice caps and 30% is groundwater. This leaves only 1% of available freshwater in the form of streams, ponds, lakes, and rivers (Shiklomanov 2013). With this knowledge and understanding, humans must now look for ways to recycle water similar to how nature has recycled it.
Wastewater Systems in America Background:
America’s population typically thinks of wastewater as what is flushed down the toilet. However, many industrial companies produce wastewater daily to go along with what Americans flush down the toilet or run down the drain. To compensate for this, over 1 billion gallons of this wastewater are treated daily across the country and either returned to flowing bodies of water or reused for things like irrigating a golf course (“U.S. Wastewater Treatment Factsheet”). With all this water being polluted, there has to be in place systems to hold and treat the influent.
When looking at residential households, there are wastewater systems such as lagoons, septic tanks with lateral fields, or they may be tied into a city’s sewage line. Each of these systems eventually treats the unclean water, however, some systems produce better treated effluent than others. Furthermore, with laws and regulations being passed yearly, the restrictions and requirements of these systems become stricter. A lagoon is “a shallow, artificial treatment pond where sunlight, bacterial action, and oxygen work to purify wastewater; a stabilization pond. An aerated lagoon is a treatment pond that uses oxygen to speed up the natural process of biological decomposition of organic wastes. A lagoon is regulated as a point source under the Clean Water Act if there is a direct surface water discharge” (“Glossary Definition of Lagoon”). Lagoons were very common in the late 1900s, but with new codes they are being outlawed for more environmentally friendly systems. Commonly, lagoons emit smells associated with sewage that people typically find disgusting. Also, industrial lagoons “were historically used to dump various liquid, solid, and hazardous wastes from manufacturing or industrial processes. These wastes typically flooded and polluted surrounding environs or seeped underground” (“Glossary Definition of Lagoon”).
Septic system that involve tanks with lateral fields either based on gravity flow or pressure dosing are very common across the country. For the gravity flow septic systems, when water in the tank rises above the outlet point, it exits into the lateral field. This allows for the space in the septic tank to be controlled. The lateral field consist of pipe, 4 inch usually, with holes in the bottom that allow the water to saturate into the ground. The pipe is typically surrounded by gravel. These systems are found to commonly fail for a variety of reasons. The four most common reasons for failure is sewage backflow, sewage in the yard, decline in water quality, and gradual environmental degradation (Lee, Jones, and Peterson 1-2). All these problems can be traced back to one thing: inadequate soil for wastewater treatment. ”The soil’s purpose is to destroy these pathogens, treat and degrade organic materials, and act as a physical, chemical and biological filter to purify the effluent and make it acceptable quality for groundwater. Soils must be capable of absorbing the volume of wastewater from the septic tank at all times of the year” (Schultheis, Fulhage, Sievers, and Miles). The proper soils must be in place for these systems to function as expected.
Homeowners tend to miss on maintenance of the tanks or believe that sending Rid-X down the toilet will lower the level of sludge in the tank. Furthermore, if a system is failing it is common to experience wetness in the yard where the lateral lines are buried. People tend to not notice until the problem requires major repairs that are costly. The decline in the water quality deals with the local groundwater sources in the area being polluted by the septic system. To determine whether this is a problem, water samples of the septic and local well(s) would be taken. Finally, since a septic system allows the solids to settle in the tank and the excess water bleeds out throughout lateral lines, the soil is the last form of treatment for the septic effluent. Over time, a bio-film can build up on the soil meaning the soil can no longer take more septic effluent. The effluent then builds up in the lateral lines and tank either leading to a blow out of the lateral lines (surfacing of sewage) or a backup of the entire system.
For pressured dosed septic tanks, the design is the same as the gravity flow septic system, but a specific volume of effluent is sent out into the laterals at designated intervals. This allows for control of space in the take, and the amount of time the soil has to absorb effluent before the next flow of water comes through the laterals. Time dosing “ensures unsaturated flow conditions, which encourage aerobic microbiological decomposition and enhance nutrient removal below the drain field” (Karathanasis, Mueller, Boone, and Thompson 178). A soils structure and texture play a vital role in the ability to treat the effluent and whether the process is aerobic or anaerobic. “In a fine-textured soil, it may be impossible to maintain adequate long-term drainage because suspended solids and biological exudates may clog many soil pores” (Karathanasis, Mueller, Boone, and Thompson 178). On the other hand, a coarse-textured soil may allow the effluent to pass through too quickly without removing the nutrients. No matter a soils physical and chemical characteristics, time dosing offers better conditions for the soils to properly handle the effluent from the septic tank.
Drip Irrigation Background:
A rapidly growing industry in the United States that is using recycled water can be found right in your backyard. Drip irrigation systems, are a type that are being installed in replace of typical septic systems or lagoons. “Drip irrigation is defined as the application of water through point or line sources (emitters) on or below the soil surface at a small operating pressure (20-200 kPa) and at a low discharger rate (1-30I/h per emitter), resulting in partial wetting of the soil surface” (Dashberg and Or 1). The advantage of drip irrigation versus its predecessor of a septic tank with lateral lines is the ability to control the application of the effluent in the system. To better understand drip irrigation, the history of its creation must be discussed.
The first to claim creation of drip irrigation was the country of Germany over 100 years ago. Scientist used “subsurface irrigation by means of drainage system” which is claimed to be the fore-runner of drip irrigation (Dashberg and Or 1). However, the most accepted origin of drip Irrigation occurred in Israel. Simacha Blass, an engineer, used the “plastic revolution” after World War II to his advantage and developed a system that used subsurface tubing with small emitters spaced along the tubing for water to “drip” out of. Blass got the idea to drip water when a farmer pointed out a tree growing randomly in a sandy field with no other vegetation. When Blass dug around the tree he discovered a leaking water pipe that had a bulb of moisture expanding water below it. This bulb had intersected with the tree roots and was allowing the tree to prosper in the arid climate. The need for this type of system arose from the dry climate experienced in Israel and the need to reuse any water they had to meet all the country’s water demands. Thus, used water was collected and transported to locations with drip irrigation systems before being released into the soil. Blass went on to partner with Kibbutz Hatzerim to create Netafim, a drip irrigation company, which engineered systems to deal with the reuse of water (“Drip Irrigation”).
“The first subsurface installation system in Israel developed clogging problems, especially by root penetration into the emitter” (Dashberg and Or 2). Multiple issues were encountered due to the soil and vegetation of Israel when drip irrigation was first being implemented. The soil in Israel is made up of mostly sandy particles of varying sizes. The sand particles would clog the emitters and prevent water from dripping out. Also, the roots of vegetation grow and orient in the direction of the water source. The emitter hole was large enough to allow the roots penetration into the emitter and clogging the exit. Therefore, Blass refined the design so “the main aspect of the new invention was to release water through larger and longer passageways (rather than tiny holes) by using friction to slow water inside a plastic emitter. Larger passageways prevented the blocking of tiny holes by very small particles” (“Simacha Blass”). Today, Netafim sell’s it patented “Bioline Dripperline” (Netafim 4) which has built in herbicide in the emitters to prevent roots from clogging the line. The emitter has been redesigned, but follows the sample basic concept of long lateral lengths which allow for uninterrupted flow of effluent. This design has led the way for the industry and continues to be standard in drip irrigation equipment.
Drip irrigation can be used for a multitude of practices both on the surface and subsurface settings. According to the Netafim USA website, five main areas of use are agriculture, green houses/nursery, landscape and turf, wastewater, and mining. Farmers use drip line in the field, at orchards for apples, oranges, and berries, and even small garden use. Mining is a huge industry in which drip line has acid run through it which drips onto open faces of rock to chemically remove copper, gold, and silver. Many business want to have manicured lawns so instead of sprinkler systems that may provide uneven water distribution, drip line in laid in the ground. Finally, the reuse of wastewater for both residential and community purposes. Drip systems are being installed for single family houses and the recycled water feeds the lawn. Meanwhile, on a larger scale, drip irrigation systems are being installed for small communities as a cost effective way of disposing of wastewater. The advantage of this is the communities are growing crops on the ground where the drip is installed to recuperate installation costs and eventually bring funds in for their local governments. Perhaps more importantly, the drip systems are recycling and reusing the wastewater and nutrients placed into the system. This cycle benefits both humans and the environment by being self-sustaining.
Onsite Wastewater Systems with Drip Irrigation Background:
Residences that are outside of city limits or not connected to a centralized sewer system in a subdivision or town will likely have an onsite wastewater treatment system. This simply means the household’s waste is collected in a tank, treated, and dispersed on the property. To install a new onsite system, “most states, local health departments issue construction and operating permits to install septic systems under state laws that govern public health protection and abatement of public nuisances. Under most regulatory programs, the local permitting agency conducts a site assessment to determine whether the soils present can provide adequate treatment, to ensure that groundwater resources will not be threatened, and to stipulate appropriate setback distances from buildings, driveways, property lines and surface waters” (“Water: Septic (Onsite/Decentralized) Systems”). The site assessment is very important in the determination of whether the property can handle an onsite system.
During the site inspection, a soil site assessment is taken of the entire property. The soil evaluator looks at the soil structure, texture, color, depth of the horizons, and if necessary can run tests in the lab such as cation exchange capacity (CEC), percent base saturation, pH measurement, bulk density, and shrink-swell capacity (Buol, Southard, Graham, and McDaniel 63-71) . The structure and texture of the soil will determine the suitability of the soil to treat effluent, its water holding capacity, and the whether it can hold up large equipment moving across its surface. When the samples of the different horizons are taken, the soil is sprayed with water to look at the color of the peds. If the soil shows a collection of gray mottle, then tends to indicate the presence of a water table. If this water table is relatively close to the surface, this could be problematic for the potential septic system. Too much ground water flowing through the potential site location would over-saturate the soil leading to a quick failure of the system. Also, having a site with a high water table would indicate a lack of aeration of the soil which would consequently prevent the soil from properly treating wastewater effluent if dispersed there. If this is the only site possible there are some options to divert groundwater flow such as placing a curtain drain around the upper most slope of the property with exit points leading quickly away from the septic system.
Another important consideration in the soil survey is the depth of the upper horizons. The depth of the topsoil is very important because this will help in determining how water will absorb and flow in the soil. Furthermore, this depth of available topsoil will help determine whether the potential of pipes freezing will occur. In northeastern part of Boone County, Missouri “the soils formed in deep loess and in loess over glacial till. They are clayey and are poorly drained or somewhat poorly drained” (“Soil Survey of Boone County, Missouri” 12). The upper portions of the soils in Boone County may show to be very good soil for septic systems, but the clay accumulates quickly below the surface or at the surface. Clay is very impermeable when saturated and when dry can leave large cracks in the soil. These extreme variances in soil conditions pose threats to the integrity of the septic system. When looking at the soils, it is extremely important to look at the location of the property in the area’s landscape. Are you standing on a summit, back slope, shoulder slope, foot slope, or toe slope? This will allow for the prediction of movement of water both on the surface and subsurface.
Once the site has been assessed, an engineering design is created for the exact location and size of the septic system which is based upon the number of rooms in the house. To size the tank, the number of rooms in the house must be known because each room can hold a least one person at any given time. Therefore, an average of 120 gallons of wastewater per day per room is multiplied times the total rooms in the house times 2 days (tank must have enough room for two days of wastewater). From this design an installer can install the system. The installer will consult with the soil evaluator, engineering firm, and local regulator to determine the type of effluent to be used. The effluent will be either aerated (mixed with filtered oxygen) or anaerobic (without free oxygen). To use drip irrigation to disperse the effluent on the property will require lower pressure pipe distribution. This system begins with a tank where settling of the solids occurs. The water left on top of the solid waste is then pulled through a pump and filtered. The pump sends the effluent through 1 ¼” to 2” PVC pipe laid in a trench (“On-site Sewage Facilities (OSSF)”). The effluent will pass through a manifold which distributes the filtered water to a section of later drip lines. The water will flow through the lines for a certain amount of time before heading back to the tank due to gravity. The system will repeat itself according to a timer.
Drip Irrigation Case Studies Background:
The first case of drip irrigation took place in Columbia, Missouri. A 24 year old house with a failed septic system on a lot that was 190 ft. by 240 ft.is the study setting. The system is replaced with a 1250 gallon concrete tank, a 750 gallon fiber glass pump tank with a screened pump vault, and 1900 ft. of drip irrigation line that was buried 8 inches below the surface and two feet of distance between each line. The designed loading rate for the system was 0.125 gpd/ft and the actual loading rate was 0.044 gpd/ft. Since the area of the lot is very small, the systems performance is analyzed very closely for performance. Measurements are made on the amount of gallons used a day compared to the amount of gallons sent out to the drip field. This shows on the typical day that around 10% of total gallons per day that was actually used in the house remains in the tank. Other test looked at the quality of soil as the drip line continued to function to determine whether the soil could hold up to the time dosing routine that was implemented. The effluent characteristics remain the same during the testing period, the system creates a slight buildup of salt in the soil due to the home owner’s water softener, and the soil shows no gain in total nitrogen. “The largest problem was encountered in September 1999 when the irrigation system was being operated manually on a routine check. The loading rates to both zones in the field had decreased from 5.0 gpm/zone to 2.0 gpm/zone” (Sievers, and Miles 18). Officials from the drip irrigation visited the site multiple time trying different methods of “flushing” the system. Eventually the loading rate returned to 4 gpm which is 80% of the original value. It was concluded that a biological film of unknown origin was developing in the dripper line emitters and in the tank that created the drop in the loading rate of the system.
The second case study analyzed was at Table Rock Lake in Stone County, located in the Ozarks of southwestern Missouri. The lake covers an area of 43,000 acres and was formed from damming the White River near Branson, Missouri. The White River is fed by the James River watershed in Green County. The concern with the lake is the accumulation of excess nutrients due to failing on-site septic systems. “A study by Aley and Thompson, 1984, found that 60% of septic systems in Green County, part of the upper James River watershed, were contributing detectable contamination to spring systems” (Casaletto, Wallace, and Miles 2). With a growing local population in surrounding towns and around the lake, the decision to take action was made. The objectives of the project was to demonstrate onsite wastewater treatment technologies near Table Rock Lake while also gaining knowledge about best management practices for this area as the population continued to grow. For the sites selected, management solutions for these systems would have to be demonstrated along with identifying any legal roadblocks that may constrict the ability of these treatment systems.
Multiple criteria were looked at when determining site locations. First, the homeowner had to apply to be part of the project, they had to show a willingness to maintain their systems once installed, and the location had to be able to support a new septic system with a drip irrigation field. Since drip irrigation was being used as the best management practice, large areas of space would be needed to lay out the drip field. This posed a couple of problems. First, most homeowners were lake front property owners with little space and the second problem is these properties had little topsoil available to bury the drip line in. Multiple homeowners decided to share their property to allow for area required to install the drip irrigation tubing and soil of specific qualities was imported into the area to lay over top of the drip line. The systems installed consisted of a tank for holding solids, micro-biotic biological reaction chamber media (foam cubes), a pump tank, and the drip line field (Casaletto, Wallace, and Miles 6-7). The lack of local top soil allowed for the installers to bring in soil that would hold it structure and be able to disperse the effluent efficiently. The homeowners deciding to share property also allowed the installers to find flatter ground that would not be as problematic had they had to install on a more sloped contour near the lake’s edge.
To monitor the system, a 12 inch innovative lysimeter was installed underneath drip line to collect subsurface water samples. Also, a lateral sampling line was installed in the same location as the lysimeter. Though periodic monitoring of the system, the researchers concluded the perception of onsite wastewater treatment systems had been changed along with affecting how systems in this type of landscape would be installed in the future. With cooperation of homeowners, these onsite systems will begin to remove the stigma as “failing systems” because once installed it is the homeowners’ responsibility to monitor the performance of the system and contact the installer if they notice changes.
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