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Street Maintenance |
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DIVISION INFORMATION
The Street Maintenance division of Public Works performs the following duties:
| pot hole patching |
| curb and gutter repair |
| right of way and ditch maintenance and mowing |
| tree removal from right of ways |
| snow plowing and removal from streets and public property |
| spring cleanup and fall yard waste cleanup |
| placement of seasonal decorations |
| street chip, seal and crack sealing |
| brush hauling |
| storm sewer cleaning and repairs |
| street striping |
| traffic light and sign maintenance |
| alley maintenance |
| installation of driveway culverts |
| landfill maintenance |
This division also assists other City departments such as the Engineering department by preparing street areas for new construction and other tasks.
Snow Removal:
There are 10 employees that perform street maintenance work on Kirksville’s 96.5 miles of streets. The City is divided into 7 zones for snow removal. An average winter has an estimated ice and snow removal cost of $63,000, which includes over 1,700 labor hours.
Landfill Maintenance:
Another little known area of Street Maintenance is landfill maintenance. This responsibility includes grinding brush into wood chips and composing leaves and grass. They also keep weeds mowed on approximately 25 acres and use the clippings for composing.
How this Division Benefits You:
Aside from keeping our roadways clear and safe, landfill maintenance provides free wood chips and compost for citizens. The wood chips and compost can be used together or separately to cover base areas of trees and shrubbery. By diverting this yard waste from sanitary landfills, the City is extending the active life of landfills.
This is the place where water from nature gets converted to water that is safe to drink. Kirksville’s water is drawn from Forest Lake and Hazel Creek Lake. Water is pumped approximately 6-7 miles to the plant and stored on a raw water pond. This pond holds about two days worth of water in case there is an emergency such as a water line break from the lakes. The storage pond is treated with chemicals which control algae growth. As with other parts of Public Works, there is always a secondary back up system should the main system fail.
Stages of Cleaning:
| Stage 1: |
Water goes through three stages of purification before you drink it. Water from the storage pond is sent to an "upflow unit" or a primary clarifier. These are big round basins with a mechanical cone that you may have seen at the Water Treatment plant.
In the primary clarifying unit, disinfectant is injected into the line from the raw water pond. "Floc" is created when added chemicals stick to the organic materials in the water. Together, they weigh more than the surrounding water and sink to the bottom in a blanket of floc. The water in the basin is slowly stirred, causing the floc particles to collide and stick together. As waster flows up into the basin, the heavier particles on the bottom are scraped to the center and pumped out to be hauled away.
| Stage 2: |
After the primary basin process, gravity causes the water to flow from the upflow unit to two secondary clarifiers. The secondary clarifiers allow more time for particles to settle out of the water. As it flows, small amounts of fluoride are added to the water in accordance with the American Dental Association’s recommendations (fluoride in our drinking water helps build strong teeth).
| Stage 3: |
Water flows through filters which contains layers of anthracite coal, sand and gravel. There are three tertiary treatment filters at the Kirksville purification plant, and a fourth will be completed in the future. After this third stage of cleaning, water is ready for consumption.
Storage and Pumping Capacity:
Each of the tertiary filters can clean about 1,500,000 gallons of water per day. Once the fourth filter is in operation, Kirksville can serve an additional 12,000 people with the extra 1,500,000 gallons that will be treated and ready for use (The average person consumes 125 gallons of water per day).
The clean water is stored in a underground water tank. Once these are full, water is pumped to other ground storage locations or to the City as needed. Kirksville can store almost four million gallons of water in its above ground tank and in the city’s four water towers. Kirksville goes through about 2.4 million gallons of water per day in an average month and there are always at least 3 millions gallons of water available for one day.
Water Pressure:
Water flows through the plant at a rate of 2,400 gallons per minute. This rate is held constant to make sure that chemical treatments are administered properly. The city maintains a pressure of 40-60 pounds per square inch (psi) throughout the distribution system. The Department of Natural Resources mandated that pressure be maintained above 20 psi. Rates lover than 20 psi would make it difficult to fight fires and to accomplish other tasks which require higher water pressure.
Safety Testing and Maintenance:
The water treatment staff tests the water in all three treatment areas and in storage areas every two hours. These tests are done to make sure that the quality of water meets guidelines set by the Department of Natural Resources and the Environmental Protection Agency.
The "floc" chemical blankets are maintained through a constant addition of new chemicals and extraction of the particles which have sunk to the bottom. The extracted "sludge" is pumped to a storage area until it can be disposed of. It is often spread on local farmers’ fields as fertilizer because it is high in organic materials and clay that were suspended in the water.
Plant Operators’ Qualifications:
Water plant operators are certified by the State of Missouri Department of Natural Resources. There are four classes of certification. Several years of experience are required before the highest certifications can be obtained.
How this Division Benefits You:
The water treatment enter supplies clean, safe drinking water to the entire community.
WASTE WATER TREATMENT DIVISION
Kirksville’s waste water treatment processes essentially accelerate nature’s own clean-up methods, through the use of bacteria and enzymes which "eat" the harmful pollutants in the water. Water velocity also effects treatment because the speed of the flow of the water will determine how much settling occurs. For example, if you stir sugar into tea, the action of stirring causes the sugar to be suspended in the tea. If you leave the tea for a while, some of the sugar will settle our. It follows that the flow of water must be monitored in sewer lines. If the water is moving too slowly the solids settle out and the in will become stopped up.
Lift Stations:
There are twelve lift stations in Kirksville. Lift stations are low points where gravity takes sewer water. The station then lifts the water by pumping it up to a point where gravity can carry it to the waste water plant. "Good" bacteria and enzymes are added at the lift stations to reduce odors and hydrogen sulfide which can build up in sewers. This gas will corrode the collection system used to transport water if it is not controlled. Each lift station has two pumps and a basin that can hold excess waste water should there be an emergency.
The Treatment Process:
Once the collection system takes waste water from the lift stations to the waste water treatment plant, two screw pumps lift the raw water to levels where gravity can take it through the plant. From there it goes to a grit chamber which settles out some of the heavier materials in the waste water. Further filtering is done by a mechanical bar screen which removes things like rags, stick and other debris.
From there the flow splits to two primary clarifiers. These performs similar functions to the clarifiers used at the Water Treatment plant. Floating debris is skimmed off the top and settled solids from the bottom are sent to two above ground tanks called digester. These digester are similar to a human stomach in that they decompose any organic materials. This process gives off methane gas which is captured and used to heat the digester tanks and to heat a portion of the plant itself. The sludge created by the digester is ultimately hauled to farmers’ fields for fertilization.
Biological Treatment:
To this point treatment has been limited to the removal of solids from the waste stream. The water flow is now pumped to a packed tower, which is an above ground tank filled with corrugated plastic media. The media give millions of microorganisms something to stick to as water is trickled down through the tower by a motorless rotating arm. As the water trickles over the media, the microorganisms consume dissolved particles that are in the water and this causes the dissolved particles to stick together, become heavy, and settle out of the water.
From the tower, waste water is sent inside the plant to flow through a series of rotation biological contactors (RBC). These provide more surface area for microorganisms to attach. More cleaning occurs through each of the Waste Water plant’s twenty RBC’s.
Exiting the Treatment Plant:
Water finally leaves the plant through a partial flume. This is where water is measured. The water that leaves the plant feeds into Bear Creek and then the Salt River Basin, and eventually the Mark Twain Reservoir. This means that our neighbors downstream depend on us to maintain a level of cleanliness in the water we treat.
This waste water treatment process requires extensive monitoring. The plant can treat 5 million gallons of water per day, but currently averages 3 ½ million per day. Treated water discharged to Bear Creek must be tested for nutrient levels weekly. Other tests must be performed daily to make sure everything is working properly. The industries in Kirksville are also monitored to make sure they don’t put any pollution into the waste water system.
Maintenance of Operations:
Extensive maintenance also comes with extensive monitoring. The equipment must continually by checked and if any of the breaks down, the back up systems must be put into operation immediately. One person checks lift stations each day to make sure the 22 pumps with 22 large motors are working properly. The gases produced in the sewer are very corrosive and would severely damage the pipes of they were not maintained properly. Hauling the sludge to farmers’ fields is also time consuming and costly.
Plant Operators’ Qualifications:
All operators are licensed by the state of Missouri to handle waste and waste water and are required to have several years of experience before they can upgrade their license. A lot of time and effort are put into this facility to insure that the water is properly treated.
How this Division Benefits You:
Because the City’s Waste Water treatment accelerates the natural processed of cleaning, it does not have a lot of harmful by-product to pollute your environment. Without proper treatment procedures the health and well being of the community and downstream water users will suffer.
The objectives of waste water treatment include:
| prevention of disease; |
| prevention of nuisances; |
| avoiding water supply contamination; |
| maintaining clean waters for the propagation and survival of fish and other wildlife; |
| conservation of water for all uses. |
WATER DISTRIBUTION AND SEWAGE COLLECTION
This division is responsible for water and sewage as it flows to and from homes and treatment facilities. There are over 100 miles of water lines, over 86 miles of sewer lines, and over 700 fire hydrants in Kirksville.
The primary responsibility of this division’s nine employees is the repair of leaks in water lines and the installation of new water lines when needed. Leaks occur naturally over time and can also be caused by severe dry periods in summer and severe cold in the winter. Sewer line breaks are frequently discovered by the department’s video camera which can actually crawl through lines and take videos of pipe interiors.
This division is also responsible for flushing the water lines and sewage lines yearly to keep sediment at minimum levels. Water is released from towers and pumped through the water mains to flush out any sediment that has settled over the year. The sewer lines are cleaned by a sewer jet cleaner that cleans using water pressure.
Other activities of this division of Public Works include monitoring new construction in subdivisions, smoke testing sewer lines, manhole maintenance, and sewer "sweeps". During new construction, contractors lay water and sewer lines according to City Code and the City then assumes responsibility for their maintenance. Smoke testing involves forcing smoke through the sewer lines to see which cracks or breaks it rises through. If, for example, it rises through the top of a factory, then the Public Works Department knows that this factory’s roof drains are directly tied to the sewer line. It could also mean that other pollutants requiring pretreatment are sent directly to the city sewer. Sewer sweeps are conducted with a high powered "vacuum" that sucks up any articles of debris that are otherwise immovable.
How this Division Benefits You:
In addition to all the work that this division does to insure safe transfer of water and sewage, they provide services which may directly affect you in times of need.
The sewer jet unit is used to respond to sewer backups. This division is able to respond on an emergency basis, 24 hours a day, seven days a week. This also applies to emergency response for the repair of water main breaks. Main breaks can be severe, causing the loss of large volumes of water from the system. They can result in street pavement damage from the upward force of the water leaving a pressurized main.
This division is also responsible for the location of water mains and sewer lines for various agencies, such as utility companies, contractors and engineers. Line locations are necessary to prevent accidental cutting of utility services during construction or maintenance work.
The central garage stores and repairs heavy equipment for all divisions of Public Works and other City offices. Each department pays a fee to cover their portion of mechanics wages and the operating expenses of the garage. Individual items of repair are charged to each department. There are two mechanics and one supervisor that can answer emergency calls for all City departments.
The central garage also tracks mileage on vehicles to perform preventive maintenance such as oil changes on vehicles. The division manages a comprehensive vehicle replacement program which calculates the total time left before vehicles must be replaced. There are currently 118 City vehicles and pieces of heavy equipment in eleven different departments.
How this Division Benefits You:
The City’s fleet represents a large capital investment, and proper vehicle care is essential. The garage has expanded its capabilities to include painting of vehicles and equipment. In-house painting is much more cost-effective than hiring the work to an outside company. Any cost savings resulting from proper fleet management will ultimately benefit the taxpayers of the City.
PUBLIC WORKS DEPARTMENT OBJECTIVES
The Public Works department is constantly evaluating work processes and procedures. Projects that the City cannot handle efficiently are contracted out to private businesses. Other tomes, department personnel can perform certain tasks at a lower cost than outside companies. This balance produces the most efficient type of operation, thereby keeping costs at a minimum. In turn, this means fewer tax increases, and lower water and sewer rates for the citizens of Kirksville. The Public Works Department is working for you by ensuring quality living in Kirksville and its surrounding communities.