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HomeMy WebLinkAboutWater Board - Minutes - 06/25/1998• WATER BOARD MINUTES June 25, 1998 3:10 - 3:45 p.m. Fort Collins Utilities Conference Room 700 Wood Street COUNCIL LIAISON Chuck Wanner (absent) STAFF LIAISON Molly Nortier - 221-6681 MEMBERS PRESENT Paul Clopper, Chair; Alison Adams, Vice Chair; George Reed, John Morris, David Lauer, Dave Frick, Howard Goldman, Joe Bergquist, Tom Sanders, Dave Rau, Robert Ward GUESTS John Bigham, Northern Colorado Water Conservancy District Jack Templeton, Science Applications International Corp. UV 1213l: :: ►I . . Chairman Paul Clopper opened the meeting. The following items were discussed: MINUTES OF APRI1,23, 1998 George Reed moved that the minutes of April 23, 1998 be approved as distributed. After a second from David Lauer, the Board unanimously approved the minutes. MINUTES OF MAY 27. 1998 Alison Adams moved approval of the May 27, 1998 minutes. Dave Frick seconded the motion. David Lauer pointed out on p.7 last paragraph, last full sentence, the "e" was left out of "we." There was unanimous approval of the corrected minutes. Water Board Minutes June 25, 1998 Page 2 1' 1 : ► • I.I t ► lZi7111Li71 0 6 VT 111Y • ► I NOTE: After 10 years as a liaison to the Water Board from the NCWCD, John Bigham gave his final report. He will be retiring from the District as of next week. A farewell reception was given in his honor at the end of the meeting. Mr. Bigham distributed a packet of information put out by the District including a printout from their web page. He said the District is hoping, in a couple of months, the entire report will be accessible on their web page. He went on to say that Granby is up to within a foot of being full. The run-off has slowed down. He suggested that Board members look at the rest of the report at their leisure. "We started out with nearly 146,000 ac-ft of carryover," he said. "We anticipate delivering about 75% between now and the next 20 days. About 36,000 ac-ft will be left over out of the entire system." Mke Smith had received a copy of the seepage report on Horsetooth Reservoir. Mr. Bigham said the report on seepage of the dam is now out. He said the dam is not going to break, so there is no need to worry. The recent publicity in the newspapers may have caused alarm for some people. "The seepage in all of the monitoring areas has dropped as the depth of the reservoir has dropped. There are no recommendations for any restrictions on the reservoir, which is a good sign," he assured the Board. It will continue to be monitored. "We are staying ahead of the problem, so whatever remedial action, if any, is required, we will do; like reducing the reservoir elevation to take the pressure off." He mentioned that some of the seepage is 300 feet below the dam, so it is deep into the geology. The report of the seepage of 1200 gallons per minute was 3/4 of a mile downstream from the dam, and also combines leaks from springs within the total seepage. He said it sounds like a lot of water and he acknowledged that it is significant, but not through the dam per se. "Things are looking better," he concluded. "Has there been any more progress in the carryover changes," Joe Bergquist asked. ]Si Bigham understands the District Board will be discussing it again at their July meeting, and will make a final decision in August. The Board still has to make a decision on a couple of items. If anybody has comments, Mr. Bigham suggested that they pass those on to the Board prior to the July meeting, or plan to attend one or both of the meetings. "What's the prognosis for Horsetooth for the rest of the summer?" I& Lauer asked. "Do you intend to keep it low, or will it be filled back up?" "It will be kept low, and when it gets down to a certain elevation, more piezometers will be installed so there will be greater coverage to record seepage. Then the reservoir will be filled again." "Are they doing any additional fill?" Mr. Lauer asked. "I would say any remedial action, other than reducing the level and monitoring it, will probably be grouting at some point," W. Bigham replied. "That's the standard process." f Water Board Minutes June 25, 1998 Page 3 Mike Smith met with Bureau of Reclamation people early this week. They mentioned that, during the next year, there will be additional monitoring of the reservoir, drilling additional well piezometers and preparation of a recommended remedial plan if the seepage gets worse. "At this point it isn't showing any more seepage?" Mr. Lauer wondered. "Actually it has gone down," Mr. Bigham replied. "It's obviously tied to pressure, since seepage has decreased as the level has gone down." Mr. Smith pointed out that the manmade portion of the dam is not the problem. It's the foundation underneath. "So it's reasonable to say that the seepage has nothing to do with the dam safety," George Reed commented. "You really can't say that. Foundations can be a problem if you get a lot of seepage," Mr. Smith responded. "If you have a failure of the foundation, you can have major problems," he added. "The construction of the dam is not a problem," Mr. Bigham reiterated, "it's the foundation on which the dam is built." "It's something we need to watch," Mr. Smith concluded. Mr. Clopper asked if there have been any dam break studies where they looked at floodway propagation and downstream inundation limits. "Sure," Mr. Smith replied, "we have some on file." Mr. Clopper referred to the Poudre River graph in the information which Mr. Bigham provided. "It looks like there is almost a perfect weekly cycle to the Poudre river flows. That isn't apparent in any of the other South Platte stations. Is there any reason for that?" "Not that I'm aware of," Mr. Bigham replied. Treated Water Production Summary Dennis Bode reported that for May the Utility treated 2,884 ac-ft which was 93% of what was projected. "June has been very similar," he said. "We are still a little below what we projected, although in the last few days there has been a dramatic rise in the demand. He referred to a graph that shows the actual water use where you can see how the demands have moved up. "We used about 48 mgd yesterday, but actually the City treated quite a lot more than that," he reported. "We have been up and down in our use, which is pretty normal." Mr. Bode then pointed out two graphs which showed Joe Wright Reservoir and Deadman Hill snotel sites. "We are basically finished with the snowmelt up there," he said. He related that the snowmelt came out more quickly this year and was a little below average. "The projections for annual flow in the Poudre River were about 75% of average this year. We were quite a lot drier than what we had expected earlier." Dave Frick asked why the projected City demand varies so much. Mr. Bode responded that the projected demands are based on 10 or 15 years of data and it's looking at a day at a time and looking at the pattern. He pointed out periods in late May and again in late July when the demands typically drop because of rainy periods. Water Board Minutes June 25, 1998 Page 4 Rainfall Study Susan Hayes came today to give a brief update on the rainfall study. The final report has been delayed, but she expects it to be completed at the beginning of next week. Staff will send the report to task force members who will be meeting sometime in July. She will be reporting to the Board at the July meeting. She continued by saying staff has been doing some in-house impact analyses. "As of last month, we just looked at hydrology," she said. "The types of increases we have seen can be expected. We have been seeing large impacts for runoff, not equivalent to the percentage increase in rainfall. Basically, all the increased rain is just pure runoff. We were seeing anywhere from a 30% increase in runoff to 2 or 3 times the increase in runoff depending on where we are in a particular basin, the type of basin it is or whether it's highly urbanized." The next step was to look at hydraulics and at some of our systems to determine how they might respond to increased flows. "Of course with Spring Creek, we know how that can function with a large amount of increase in flows." She said they took some models that are up and running and started incrementally increasing flows by 30%, 50% and then doubling the flows. "As you might expect, a lot of the open channel sections along parks function pretty well. We can handle that kind of increase in flow in our freeboard." The restrictions are mainly at road crossings. "With the types of improvements we have already done, like Stuart and Stover, we might have problems with increasing water surface elevation and not being able to put it in the channel. We have a lot of investment in property that we have already built that could be impacted. However, it's gratifying that Stuart and Stover can take quite a bit of extra flow." The next step, along with finishing the task force reports on the rainfall analysis, is to hire a local consultant that does a lot of land development, and have them take a standard single family development and actually apply our criteria to it using increased rainfall. That might give us a feel for how it may increase development costs. We have criteria for how much water you are allowed to have in the street, how big your inlets need to be, how big your pond needs to be and how much freeboard you need. The consultants would be able to tell us, for example, that developers need to raise lots or have to lose 10 lots to have a bigger pond or put in a far more extensive storm sewer system. "So you are going to go back to existing development and rebuild for a higher standard, or is it for new development?" Mike Smith asked. "There are a lot of developments that we could justify for higher rainfall too that are already set out in storm models and are pretty well self contained," Susan Hayes replied. "Keep in mind that it's going to be unique to one site, but I think the development community will certainly step up and be able to answer our questions about how this might affect them. They will be the next group of people involved in the process before we make any decisions." she said. Ms. Hayes then asked for questions and comments. "In your runoff analysis, how much did you increase the short duration intensities?" Dave Frick asked. "That is a problem and we are seeing really 11 Water Board Minutes June 25, 1998 Page 5 high flows because of it," Ms. Hayes answered. She added that staff has just proportionately increased the distribution, so you get really high short term durations. Distribution is something that we will look at. We would never arbitrarily take our current distribution and proportionately increase it by 28%, for example. We would have to look again at our distribution and how we would modify it. "Did you say your draft report will be coming out sometime next week?" Mr. Clopper asked. "Yes, and we will be giving it to the task force members," she reiterated. She added that she doesn't think staff is in a position to ask the Board to make a decision on this in July, "because you won't have all the facts." Dave Rau asked if staff was going to look at a range of rainfall increases. "We picked two rainfalls," Ms. Hayes responded. They have come out of the preliminary results of the task force; they are 3 �/2 in. and 4 1/2in.," she said. "That represents a total of 55% increase from the current 2.9" to 4.5 in." "Isn't it going to be in the interest of the development company to minimize the effects of rainfall on a development?" David Lauer asked. "Yes," Ms. Hayes replied. "This is not a development company, it's an engineer that typically does land development. They are going to take a design that has already been applied and has already been approved, or close to being approved. We will pay them to go back and redesign the system on a conceptual level with higher rainfall rates," she explained. She reiterated they would determine, for example, how much bigger a pond would have to be and how much more they would have to invest in storm sewers to meet the street criteria. Conservation and Public Education and Engineering David Lauer reported that the joint Committee is attempting to prepare a white paper for looking at the possibility of recommending to the City Council that they reassess policies with regard to development in the 100-year floodplain. He said the Committee was doing fine until they ran into a couple of complications such as determining what the Committees' goals are and defining what we are going to allow in terms of development. There were also some questions about how we were defining the kinds of things that we would allow in the 100-year floodplain and how we were defining the 100-year floodplain; whether we were talking about the Tinge or the entire floodplain itself. "Basically, we are going to have to go back to square one," he remarked. He said Ms. Hayes suggested they look at master plans basin by basin and use some of the language in those to determine what the goals should be. "Our primary goal is health and safety," he emphasized. Some of the secondary goals are minimizing damage in the floodplains and making sure that we maintain the integrity of the ecological systems and wetlands. "Some people on the joint committee thought that was a little too vague," he related. They think the Committee should make it clearer what they mean by health and safety. Water Board Minutes June 25, 1998 Page 6 Tom Sanders, chair of the Engineering Committee, said he has an easy solution for all this, and that is "just don't build in the floodplain." "I think we need to look at it realistically, but we tend to slide back and start granting variances," he stressed. Dave Rau commented if you build in the floodplain, you should expect that "you will get your feet wet from time to time. It is a decision that people make. If they willingly build in the floodplain and get wet, I don't have much sympathy for them," he said. Dr. Sanders thinks 90% of the homeowners don't know they are in a floodplain. He contends if you are in the floodplain, it should be on the deed. "The real estate community hides that from them too," he said. Joe Bergquist said he would like to see an environmental/watershed type of concept that places a wide ban on development through some of the areas. Mr. Lauer said the joint Committee will come back next month and see what progress they can make in producing a position paper, after having looked at some of the basin by basin master plans. Mr. Clopper suggested that perhaps the two Committee chairs and he could get together with Bob Smith, Susan Hayes and Marsha Hdmes and try to get a sense of direction by looking at some of the master plans. They can also develop an organization process that might be helpful for the next joint Committee meeting. None of the rest of the standing committees had reports. OTHER BUSINESS There was no other business. Since there was no further business, the meeting was adjourned at 3:45 p.m. John Bigham was honored at a reception following the meeting. The Board and Staff sincerely appreciated his dedication to the Board by attending Water Board meetings for ten years to update the Board on activities of the Northern Colorado Water Conservancy District. Mr. Bigham will be retiring from the District as of next week. During his tenure as a liaison from the District, Mr. Bigham provided timely information, and answered many difficult questions graciously. His reports to the Board were always thorough and to the point, often injected with a touch of humor. The Staff and Board will miss his warmth and friendly greetings. Water Board Seqfetary