Alternative S.E. Bench Water System Proposal

By Rob Garner

Alternative System Recommendations

First let me say that the city has initiated several good projects that go a long way to solving our city’s water issues in the northern and southern part of the city. In fact the actions taken to date should solve most of our city’s water issues that were to be addressed under the Water Horizon project, those being water pressure issues, water volume issues and water storage issues in the northern part of the city.

Original System

To better understand our system and the needs of the city it’s helpful to understand where we started in the process. Specifically in the southern part of the city, the replacement of the old 12 inch (old timers in the water department say this line was actually an oval shaped 10 inch line) was a much needed project. This was a line which served as a combined distribution system and transmission pipeline system between the 23rd Street reservoir and the 36th Street storage.

System before the Improvements
(Click to enlarge image)

This old single pipeline system provided both water distribution to the neighborhoods via laterals (water lines that feed the neighborhoods via connections off of this main pipeline) and acted as a transmission line to the storage tanks at 36th Street. The combined demands exceeded the capacity of the pipeline as well as created conflicts in pressure regulation of the system. The city has now decommissioned this line and replaced it with two separate pipeline systems.

Further to the south the city’s water system and 46th Street reservoir was supplied solely to by the WBWCD (Weber Basin Water Conservancy District). An independent water supply source that does not belong to the city and where the city has to purchase water from WBWCD to meet the city needs. This supply source has only so much capacity to deliver water to our system and it was realized that this supply source could not keep up with our potential requirements during peak requirements such as in times of emergency or when looking to future growth. As such it was recommended to the city that the city inventory more water (i.e. build additional storage) at 46th Street reservoir location to compensate for any temporary short falls that this supply source may present to the city. This was the reason that the CIP budget included the construction of an additional tank at 46th Street.

City’s New Proposed System

According to the description of the new system provided to me by the City Engineer, Justin Anderson, the city is installing a new 10 inch distribution system that will feed directly from the 23rd Street reservoir to the neighborhoods and a new 16 inch transmission line that will deliver water to the 36th Street storage. The 16 inch line will have over twice the delivery capability of the old system and it will be dedicated almost exclusively to supplying the storage tanks.

City Proposed System after Total Build Out
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Under the current design the city would also build, at a later date, another 1.25 million gallon tank above the 36th Street tank. This tank would be connected by pipeline to the 36th Street tank with a new pipeline and new pump station and this tank would then be feed directly off the 36th Street tank. Then at some later date yet, an additional new pipeline would be installed that would transfer water from this tank to the tank at 46th Street.

The problem with this proposed amendment is twofold. One the added cost of the 1.25 million gallon tank and the placement of this tank where the city to date does not know where the demand for this tank capacity will be at this time. Secondly and more importantly the delayed timing of increasing the availability of an additional water supply source or creating more storage volume to portions of the city served by the 46th Street tank. An additional supply/demand situation that was to be addressed and corrected in the Water Horizon Project that identified a need and provided for it under the CIP budget as it was originally conceived. The amended system as proposed by the city will not meet the approved General Plan until both the 1.25 million gallon tank and the pipeline between that tank and the tank at 46th Street are constructed, which are not part of this amendment. Those additions to the system are not part of this amendment and will not be initiated until sometime in the future and then at additional cost to the city over the cost of the original proposal which would fulfill this need.

Alternative System
(Click to enlarge image)

In order to accomplish this alternate designed system, the city would need to provide adequate pump capacity to feed all tanks on the distribution system. Additional pumping capacity can easily be added to the new system. I would suggest using a larger variable frequency drive (VFD) pump system (a very commonly used type of system) at the 23rd Street reservoir that will allow the city to conserve electrical costs and adjust flow rates to meet demands. These pumps run at varying speeds based on demands or based on instructions thus creating what ever pressure or flow rate the system requires based on demand. These pumps can operate on specific preset conditions or be taken over by water system personnel in times of emergency from a control room computer. The city by State regulation should also have a second similar back up pump that is plumbed into the system and ready to go on line in a seconds notice as well as a stand-by generator.

Additionally the city should install a SCADA system to monitor and control all pipeline pressures, tank levels and flow rates on the system from a single location which is currently not the case and was one of the higher priority recommendations over any tanks in the southern part of the city under the study used to develop the Water Horizon Project. The SCADA system would allow city employees to spend their time more efficiently in the repairs to the city’s water system rather than babysitting all the valves, pumps and water levels on the tanks on our system.

With regards to additional storage at 36th Street, I find no State requirements that mandate that the city increase storage at this location. In fact in the State’s last audit of the city’s water system, it found that the city had adequate storage at this location and that’s the last time anyone would have said anything about our tanks. The water demand volumes presented in the CRS study are suspect at best in that they far exceed the levels that other communities in the state build to and the storage volume requirements are based on the assumption that the entire undevelopable property located within zones 4 & 5 (including areas that are set aside by the City’s General Plan as protected areas and zoned as open space) would be included in the city’s demand requirements on this tank. Additionally the city is inconsistent in its requirement for the tank at 36th Street in that it is not requiring these same levels of water storage relative to fire storage or emergency storage at the new 29th Street or existing 46th Street tanks.

For a second though if we assume that the city is correct and the water volumes are needed at this location, it would be much less expensive to repair the existing tanks than to replace them. In fact steel tanks are only about 1/3 to1/2 the cost of cement tanks (depending on the size) and no more expensive to maintain. I would be glad to get a steel tank fabricator to verify these cost numbers. Besides, it would be much simpler and much less costly to just add one more tank to the existing tanks up there or replace the smaller of the two with a larger one. Personally I feel the two tanks at 36th Street are in much better condition than city claims and if they are in need of some repairs the repairs can be done for a fraction of the cost of a new steel tank. It is not uncommon to replace floors or even side walls on steel tanks without replacing the whole tank. This can not be said for cement tanks, there is no such thing as a small crack that can be fixed with a cement tank.

Conclusion

The alternative system that I proposed above will not only meet all of the original project objectives but will also save the city at least $5 million dollars in construction costs. Additionally it will give the city’s water system more flexibility and an opportunity to actually offset some of its cost through the sale of city surplus water.

This proposed amendment which you are being asked to approve is a deviation from the original proposed CIP budgeted project. In fact it actually fails to accomplish the intentions of the approved Water Horizon project by not addressing the immediate needs within the southeastern part of the city and then some time in the future when these needs are addressed it will be at additional costs over the original proposal. Please do not find this amendment to be in compliance with the general plan.

Ed. Note: Ogden Resident Rob Garner has been employed in the oil and gas industry, dealing with tank and pipeline issues for over thirty years. During the previous six years, Mr. Garner participated in the design, operation and oversight of more than $6 billion in tank and pipeline construction for Kinder-Morgan Energy Partners (NYSE: KMP), the largest pipeline operator in the world.