Despite being pounded by two major hurricanes followed by record flooding in a matter of weeks last fall, North Carolina pork producers compiled an amazing environmental safety record.
From those devastating storms, only about one hog lagoon in 10 had any leakage problems. A small handful experienced serious manure spills or breeches of the system.
Julian Barham's 4,000-sow, contract farrow-to-wean operation near Zebulon, NC, just east of Raleigh, is a case in point. Although his farm didn't catch the full brunt of the storms, he still received about 21 in. of rain.
Barham has never had a manure spill from his two-stage lagoon. Attention to detail, he says, is the key to his clean record. He keeps his lagoon well pumped going into winter, a time when there is less evaporation from the non-porous, heavy clay soils and therefore, less chance to irrigate effluent.
Adding Some Assurance Last July, before the storms struck, Barham decided to add some assurance to his lagoon system. He purchased a lagoon monitoring system from Strison Wireless Systems of Greensboro, NC, which provides an early warning signal should lagoon levels get too high. Alarms are set at 19 in., 12 in. and 1 in. of freeboard.
The system also activates an alarm if lagoon levels are dropping too fast. Alarms are sent to pagers or e-mail addresses as needed.
Randy Jones, Strison vice president of sales and marketing, says the solar-powered system holds two advantages for Barham. It provides an extra set of eyes and ears and peace of mind in knowing that the lagoons will be monitored when Barham is not there. And it enhances public relations with neighbors and state environmental regulators.
"We are finding that there can be some value in the neighbors around a hog farm knowing that a lagoon system is being monitored by the latest high-technology equipment," says Jones.
It saves a lot of time and trouble in meeting state environmental rules, too, relates Barham.
"Every week we are supposed to write down the amount of freeboard we have in our lagoon to the state Department of Water Quality. Also, naturally on a hog farm, you have to keep up with your rainfall. The nice thing about this system is that it does both things for you automatically," he explains.
Also, pinpointing the exact amount of freeboard using the wooden "start-stop" pumping gauge installed at the lagoon's perimeter is a difficult task, argues Barham.
"Using the gauge, I'm estimating it based on inches, and I could be off 6 in. The Strison system accurately measures it in tenths-of-an-inch increments," he adds.
Those measurements are made using an ultrasonic sensor mounted on a boom, which extends over the lagoon (see photo). It takes readings of the level of the lagoon's surface, explains Jones. It works like a Navy sonar device. It sends out a signal and measures the distance based on the time it takes for the signal to bounce back, says Jones. If there are waves on the lagoon, it will record and average out the reading.
"We chose that kind of sensor because you don't have to get out into the lagoon," explains Jones. "If maintenance is required, you loosen the stainless steel cable fittings, swing the boom in, make adjustments, then swing it back out over the lagoon when completed," he says.
Readings, taken every 20 minutes, are continually compared to alarm thresholds. If a threshold level is reached, the system immediately transmits an alarm signal. The system also continually monitors rainfall, comparing it to lagoon levels and backup battery charge levels.
Normal data recorded by the Strison lagoon monitor is posted to the customer's account on the Strison Web site, which can be accessed only by the customer using his/her personal username and password. A standard signal is sent once a day when no alarm signals are transmitted, says Jones.
The lagoon monitoring system sells for $1,995 and comes partially assembled. The monthly monitoring fee is about $25.
The wireless, remote monitoring system also is used in barns and greenhouses to provide monitoring for power, ventilation, temperature and water pressure readings.
For more information on the Strison system, contact Jones at (336) 279-1070, e-mail: randy.jones @strison.com, or visit the company Web site at www.strison.com.
Solar-Powered Lagoon Monitor A former irrigation equipment operator and farm maintenance worker who formed his own company three years ago markets a solar-powered, hog lagoon monitoring system.
Randy Sutton developed the Nutri-Re-Con lagoon monitoring system to provide producers with an accurate baseline for determining if their lagoons are being managed effectively.
By knowing the true level of your lagoon to a tenth of an inch, you can evaluate irrigation operator efficiency, building wash-downs and the impact of rain, says Sutton, president of Enviro-Safe Control, Warsaw, NC.
You also can check lagoon levels before storms strike to determine what actions to take and assess the impact of storms after they've struck, Sutton points out.
This can be a big plus on large integrator farms where it can be difficult to visually inspect large numbers of lagoons.
The Enviro-Safe monitor uses a sensor attached to a line that extends down 6 ft. into the lagoon. The unit continuously monitors levels and rainfall accumulation. It automatically records this information every 12 hours.
If the monitor detects the lagoon level is in the danger zone or is experiencing any type of abnormal activity, an alarm is triggered immediately and a signal is sent out on the unit's cell phone to the company's central computer.
The computer dials numbers from a personal list until a live person is reached on the telephone, he stresses. The raw data is downloaded into an easy-to-read, weekly graph and data chart, which is sent to the customer via e-mail, fax or mail.
The lagoon monitoring system sells for $2,695 fully assembled. The monthly service fee is $20.
A number of alternative manure handling systems have been developed for hog operations. They vary widely in initial and operating costs. Some are highly experimental and unproven.
Study these factors closely before signing a purchase contract. Develop a checklist and consult technical advisors, suggests Kelly Zering, Extension specialist and agricultural economist, North Carolina State University.
Obtain financial assurance guarantees before committing to a costly manure treatment system that has limited on-farm performance history, he adds.
Taking these precautions can help ensure you will end up with a system to fit your needs and your wallet.
Manure System Checklist Review these points before proceeding:
* What problem is the alternative system intended to correct? Clearly identify what needs fixing in the current waste handling system.
For example, if the problem is odor, pinpoint whether the source is the lagoon, the spraying of effluent, the buildings or some combination of these sources. Replacing the lagoon may not solve the problem, observes Zering.
* Decide if the system or the management is the cause of the odors. The National Pork Producers Council's On-Farm Odor/Environmental Assessment Program can provide assistance.
* Consider feed, facility and manure application options. Increased phase feeding, amino acid and phytase supplementation can affect manure management. Facility changes including flooring, ventilation and types of feeders and waterers may have an impact. Adding "windbreak walls," creating visual buffers and altering management practices can help reduce odors.
* Develop selection criteria for an alternative manure treatment system. Review regulations, land requirements, manpower needs and reliability under adverse weather conditions.
Also, consider susceptibility to spills and how the system performs across different seasons. "Many treatment components rely on microorganisms to digest organic matter. These systems may have much lower treatment rates during cold seasons," points out Zering.
How a new system is compatible with building design, its impact on odor and the balance of land-applied nutrients are other factors.
* Assess costs and benefits of alternative systems, including expected life of capital investments, prices of inputs and outputs. Realize that system performance may not live up to company projections.