Guidelines help beat effluent odds
In recent years, the use of effluent water for golf course irrigation has become the rule more than the exception. Five years ago, the use of effluent affected only about 30 percent of the golf course irrigation systems we designed. This year, nearly 90 percent were required to make use of effluent.
For many golf course projects, the reason for using this water is clear, but the understanding of how to implement its use is an entirely different matter.
The biggest mistake that I see golf course personnel make is entering into an agreementwith the effluent provider before there is a full understanding of the course’s irrigation requirements. This can create a serious problem between supply and demand, particularly for a new golf course project.
To help navigate through the process, it’s wise to consider a few guidelines.
* Use experienced professionals — First, courses should involve an irrigation design firm before you negotiate your agreement with the effluent provider. Since this water will be used for irrigation, courses will need an experienced professional to evaluate the needs of the irrigation system and determine the best way to receive and store the effluent.
* Insist on random testing – In my experience, effluent providers will test the water at a set time when they know all of the parameters are in the acceptable ranges. This does not necessarily insure the water quality that you will receive. If your provider will not agree to random testing, at least insist on the test being done just prior to the delivery of the water. This information should be provided daily to the course superintendent. The main water quality concerns courses will be looking at are biological and agricultural.
The main biological concern with effluent is the treatment level. The level for irrigation use should be at least “secondary.” This is usually considered “IQ” or irrigation quality water and is considered safe. The most advanced treatment is “tertiary.” This follows many of the same treatment processes as drinking or “potable” water. Superintendents should be most concerned about sodium and carbonate levels because they affect turf growth, soil structure and soil pH.
* Delivery and storage options – Effluent is supplied in several different ways. The most common is the gradual delivery of water over a 24-hour period. This water is stored in a lake or a tank located on the golf course. On average, the effluent supply rate is generally half of the gallons-perminute (gpm) rate that the irrigation pump station discharges at full capacity.
Storing the effluent in a lake on site is preferred. This will create a buffer between the daily irrigation water and the typically lower effluent supply rate. Also, this will give the staff the ability to evaluate the water quality and address any problems before you distribute the water throughout the course. With this storage lake configuration come environmental issues. In some cases, the lake will need to be lined with an impermeable material to ensure the separation of the effluent from the groundwater. Courses should consult with a civil engineering firm to make sure they are in compliance.
Storage tank option – The other on site storage method is the use of a storage tank. The use of a tank can be problematic, as this configuration can be restrictive because of the finite amount of water stored in relation to the fluctuations in daily irrigation demands. Also, it is usually difficult to find a location on a typical course for a tank large enough to store a daily requirement of irrigation water,let alone providing any buffer.
* Direct supply – The least favorable way of receiving water is “direct supply.” In this method, the course receives the water directly into the irrigation mainline, or booster pump, for direct distribution through the system. This configuration can result in inadequate operating pressure required for proper irrigation equipment performance.
The method of boosting the pressure is difficult, due to fluctuations in the supply pressure. This is primarily due to the fluctuation in flows that are typical of an irrigation system operation. If the supply pressure fluctuates substantially, the irrigation booster pumps cannot respond quickly enough. This is even true with variable frequency drive (VFD) controls. The result can be a high- and low-pressure shutdown of the pump station.
With all of these points to consider, it is important to note that each can have an effect on the amount you will pay for the water. The fees are set on a “cost per thousand” basis. This averages around 20 cents per thousand gallons. This cost fluctuates based on whether the effluent provider will be required to store the water after treatment or if they deliver the water as it is treated. Your effluent provider will want to set a minimum water delivery amount. This should be carefully considered, as this can commit you to water that you cannot use or dispose of.
Hal Kilpatrick is president of Irrigation Services Group, Inc, in Delray Beach, Fla.
Copyright United Publications, Inc. Nov 2001
Provided by ProQuest Information and Learning Company. All rights Reserved