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HomeMy WebLinkAboutWater Board - Minutes - 03/23/2000FORT COLLINS WATER BOARD MINUTES March 23, 2000 3:15 — 5:35 p.m. Fort Collins Utilities Training Room 700 Wood Street COUNCIL LIAISON WATER BOARD CHAIR WATER BOARD VICE CHAIR Chuck Wanner Tom Sanders — 491-5448 John Morris — 491-0185 (not present) STAFF LIAISON Molly Nortier—221-6681 ROLL CALL Members Present: Tom Sanders, Chair; John Morris, Vice Chair, David Lauer, Joe Bergquist, Robert Ward, Paul Clopper, George Reed, Bill Fischer, Dave Frick, Dave Rau, Tom Brown Members Absent: None STAFF Mike Smith, Wendy Williams, Dennis Bode, Jim Hibbard, Bob Smith, Kevin Gertig, Marsha Hilmes-Robinson, Beth Molenaar, Paul Weiss, Dennis Sumner, Sue Paquette, Molly Nortier GUESTS Gene Schlieger, Northern Colorado Water Conservancy District (NCWCD) Timothy Wilder, City Planner Scott Hogan, Ayres & Associates MEETING OPENED Chairman Tom Sanders opened the meeting at 3:15 p.m. The following items were discussed: MINUTES Paul Clopper moved that the minutes of February 24, 2000 be approved as distributed. Bill Fischer seconded the motion. Molly Nortier pointed out that Beth Molenaar's name was omitted from the staff present list. Tom Sanders referred the Board to p. 6, 5a' paragraph. Sentence one should read:... to protect these areas from the 100-year floods, most of the trees along the ditches "will have to be removed." The minutes were approved unanimously with these corrections. Water Board Minutes March 23, 2000 Page 2 UPDATE: NORTHERN COLORADO WATER CONSERVANCY DISTRICT Gene Schlieger distributed the latest snow pack - precipitation update from the NRCS SNOTEL sites as of March 23, 2000. Because of the full agenda, Mr. Schleiger said he would touch on just a few items and then allow the Board to ask questions. He began by saying that over the last 10 days, the snow pack hasn't changed much. "We are holding at 95% - 100%, so we are in pretty good shape." He announced the District's Spring Water Users Meeting on Tuesday, April 11, 2000 at the University Park Holiday Inn. He encouraged Board members to attend. There will be a great deal of discussion regarding the Horsetooth modernization project. The District is contemplating the best ways to proceed with the project. Mr. Schleiger acknowledged that it is going to present some problems. At the District's April board meeting the Board will be asked to issue some non -charge water so water can be removed from Horsetooth. "Currently, we are at about 140,000 acre feet of storage. By the end of September, we need to be down to about 30,000 ac-ft," he said. At this time, what the District is anticipating, is to have an operational range of between 30,000 and 50,000 ac-ft. Initially they were hoping for a time frame of about 2 years for completion of the project, but the Bureau believes it will probably be more like 3-5 years. That could create some additional problems. With the reduced ability to store water over here during the summer months, the District is looking at probably having to spill 60-70,000 ac-ft on the west slope. At this point, Granby is about 9 ft. from being full. He said timing becomes an issue over there. "If we start releasing at this time, we cause ice jams in Burns Canyon, and it backs up water in Hot Sulfur. If we wait another 30 days, we have the problem of evacuating enough space without flooding some of the floors of houses along the river," he explained. Mr. Schleiger then asked for questions and comments. "When you were talking about taking non -charge water, were you saying that you would be subtracting 30,000 ac-ft from the 140,000 ac-ft that we currently have, or going down to 30,000 ac-ft?" George Reed asked. "We have to get down to 30,000 in September," Mr. Schleiger replied. "What we are trying to do is to work with a number of local ditch companies to see if we can re -regulate how some of the ditch companies and reservoir companies have been operating their reservoirs. Part of the problem is, between the full elevation of Horsetooth, and down to the 30,000 storage, we are looking at 95- 100 vertical feet. When we get to the 30,000 range, we are going to be well below the level for any recreational programs, etc. We would like to keep it as near the 50,000 ac-ft as we can for recreational uses up until Labor Day. But if we get a week's rain in August and we don't have any demand in September, we will probably have to dump water down the River. In addition, we are asking local ditch companies and reservoirs to operate theirs differently and pull their reservoirs a little harder in the summer, so we can hold more water here. However, most of the reservoir companies have recreational leases as well," he pointed out. He emphasized that there are a number of major problems that need to be solved or alleviated. Water Board Minutes • March 23, 2000 Page 3 "It sounds like the District is going to be walking a tight rope with some of these issues," Paul Clopper remarked. He asked a technical question out of curiosity. "Has it been ascertained for certain that the seepage is coming through limestone dissolution; in other words, it's not a theory?" "It's been proven," Mr. Schleiger replied. The west side of Horsetooth Dam is where the seepage is occurring, and it is coming down through the limestone formations. He explained that the back side of the dams will be stripped of all the riprap and protective coverings. Then they will build filter zones on the back side. There will probably be a couple of zones with material that will be 10 feet thick, from a very fine sand to gravel, where they can get the drainage down through a given spot. "The one thing we are trying to eliminate is any movement of soils through the center core of the dam," he stressed. "When the dams were built in the late 1940s to early 1950s, this type of technology that I just described wasn't incorporated." He emphasized that there is no fear of the safety of the dams; they are sound. He explained that back when these dams were built, Fort Collins had about 10,000 people below the dams. Now, when the BOR runs through the dam hazard ratings, if one of the dams fails, there are now 110,000 people to think about. There is also a need to address earthquake situations, and determine at what level we would be able to withstand those. He continued by saying that once the back side of the dam is stripped and a couple of filler layers are put in, they will bring in a mass of material and buttress up against the back sides of the dams. That will probably vary from an additional 50 to maybe 100 feet in width. "So their strategy is let it seep, and buttress against the seepage, rather than trying to block it?" Mr. Clopper asked. "The other thing that will occur on Horsetooth Dam, is to start from the west side of the dam, at least half to 2/3 of the way across, and construct a grout curtain. The curtain would go down somewhere between 450-500 feet," Mr. Schleiger responded. They are trying to detemine how that can be done. He described one method of how they hope to accomplish it, which is to virtually cut the center core out of the dam, and come up with a zone. Or, there has been some discussion of coming down with caissons and basically drilling down to 475 feet (to bedrock beyond the limestone seep) and filling it with concrete. "What is the point of having the grout curtain come up higher than water level?" David Lauer asked. "I can't tell you that they are going to do that," Mr. Schleiger answered. He said he would guess that it would come up to that level, but he hadn't looked at it closely. He added that you are only talking about another 25 ft. He mentioned that the inside of that dam is saturated. Before you can get in and start doing what has to be done, you must get the pressure off the front side, so it will be stabilized inside. He reiterated that it's going to be a long process. Tom Sanders wondered how long it took to build all of the dams in the first place. Mr. Schleiger didn't recall how long it took, but said, "It's probably going to cost more to repair the dams than it cost to build the project." Dr. Sanders urged staff and Board members to attend the District's spring water users meeting on April 11`h to learn more about this project. Water Board Minutes March 23, 2000 Page 4 WATER SUPPLY PRESENTATION Dennis Bode, Water Resources Manager, began the presentation by saying that Water Resources staff has been looking at the City's water supply for the last couple of years. Today is an update on what they have looked at. He said this is good background information as we get into some issues in the next several months. The areas he and Water Resources Engineer Paul Weiss will cover are: 1. Historic Water Demand 2. Historic and Existing Water Supplies 3. Water Demand Projections 4. Supply and Demand Modeling 5. Potential Water Supply Issues 6. What's Next Historic Water Demand There were graphs that showed the historic treated water demand for the Utility Service Area from 1960 — 2000 and the historic water supply and demand from 1970 — 1995. Mr. Bode pointed out that in 1960 the population was 27,500. Today we serve about 118,000 people. The second column in the first graph showed the treated water that has actually been used and the third column was an adjusted number which showed the average annual treated water based on an average year. They also added in column 4 the estimated additional raw water sources that have been used over the years. He explained that this is the water the Utility sends to the Parks Dept. for the irrigation of parks, golf courses and cemeteries. In the last column the estimated total water supplies used have gone from less than 10,000 ac-ft in 1960 to about 35,000 ac-ft in 2000. The second graph showed the average annual yields based on conversion factors the Utility uses when it accepts water from developers, the firm yield for a 1 in 50 drought and the average annual treated water demand. At this point the focus was on treated water supplies. Historic and Existing Water Supplies The primary sources of water are Poudre River direct flow, Joe Wright -Michigan Ditch, NCWCD (CBT), North Poudre Imgation Co. and the Reuse Plan with PRPA. Some of the other supplies are primarily the Southside Ditches. Another graph depicted the historic average annual yield from these sources. The next graphic showed the percentage of ownership the City has in local irrigation companies. Mr. Bode pointed out that the City owns 18,800 units of CBT water out of the 310,000; that's about 6% of the CBT system. The other important number was the North Poudre Irrigation Co. shares, of which the City owns 35%. Each share contains 4 units of CBT water, which represents about 14,000 units of CBT. If you add both CBT and North Poudre shares, there are about 33,000 units of CBT water that the City has available for its use. Water Demand Projections Mr. Bode said this is a "crystal ball" kind of area. The challenge is trying to predict what are reasonable population projections for the future. He displayed a map of the Urban Growth Area Water Board Minutes • March 23, 2000 Page 5 (UGA). Within that area the blue color in the middle represents the current Utility Service Area. To the northeast is the East Larimer County Water District (ELCO), and on the southern end is the Fort Collins -Loveland Water District service area. He also mentioned that the City has areas outside the City that we serve, and part of that is in the West Fort Collins Water District. The arrangement the City has with them, is that they provide the City with raw water (CBT water); we treat it and return it them. Next Mr. Bode showed a table with population projections for Utility/City service areas from 1998 — 2040. The first and second columns - Utility service area, inside and outside City; third column — Total Utility service area population; fourth column — Water District service area population inside UGA; fifth column — total Utility/City population; and the final column — Total less Water District existing population in UGA. The projected populations were also shown in a graph. From there, staff converted population into water demand numbers; again, these are the treated water demand numbers. Basically, under the Utility Service Area, by 2040, we project the use of about 41,000 ac-ft, whereas, for the total area, about 54,000 ac-ft. If you subtract just the existing water district service area, it would be about 50,000 ac-ft. Our firm yield, as compared to these numbers, is presently about 35,000 ac-ft. The next graphic showed the historic demands from 1960 to the present and the projected demands for the three service areas. Robert Ward asked if there are records that show what kinds of projections we were using in 1960 to plan for the future, and how well we actually did with those projections. There are various reports that show those projections; some of them are fairly close and some are quite a bit off. Mr. Ward had been to a meeting recently where there was discussion about the lack of our science and technology to do projections like this. The person who was discussing this criticized what we had done in the past. "I think the difficulty is primarily in the area of population projection," Mr. Bode responded. "If you look at an earlier graph where we looked at a population increase of 4.35 times the 1960 population, our water demand was almost the same proportion. We have seen some decrease in per capita use, primarily in the last 10 years, but up until that time it was fairly constant on a per person basis. The closer you can predict the density of the population, the closer the water demand." "I assume that probably the old projections didn't recognize the fact that we would have metering," Mr. Ward pointed out, "and that might have overestimated the demand." "I think it might have been overestimated," Mr. Bode said. "Most of the difference would be in the population projections." Safe Average Annual Demand Paul Weiss continued by saying that there has been an ongoing effort to try to quantify the safe average annual demand numbers by looking at different hydrological periods, as well as different scenarios with different facilities in place, such as enlarged pipelines and storage capacity. He began with a system analysis flowchart. Staff has been using two primary data sources: one is the time series data using virgin flows generated for the 1985 drought studies, for 1-in-50 and 1- in-100 year droughts. The other source is historic data with a time frame of 1951 — 1980. Some of the input data that they are using is ditch company ownership, storage capacities such as an Water Board Minutes March 23, 2000 Page 6 enlarged Halligan and possible gravel pit ownership. They are also looking at population numbers and contractual obligations. Taking that input data, they used some regression equations that are estimated from an earlier drought study, and they are applying those to come up with system yields. The system yields represent the yields from all the different sources of water that we might own. We also come up with treated demands. These are plugged into a simulation model, which is run for a 30-year period on a monthly timestep. They then do some queries on the output and come up with the results, the key numbers being safe average annual demand. They came up with the following definition of the Safe Average Annual Demand: The maximum average annual demand that can be satisfied with the given supplies and facilities. A 30-year hydrologic computer simulation containing a representative drought was used to determine the "Safe Average Annual Demand". Then they will look at the maximum demand that we are able to meet; they will take the average of the annual demands, and that will be the Safe Average Annual Demand. Mr. Weiss admitted that it was rather confusing, but he said he would get into some graphical representations a little later in the presentation. David Lauer asked if it was average over annual or average through time. "It's the annual average," Mr. Weiss replied. "If we have 30 years, we will take the annual for each of those 30 years and average over the period. "And is that different than firm yield?" Dave Rau asked "It's used synonymously with firm yield," Mr. Weiss replied. "It's really out of that total that we have to treat." "Is it part of our raw water supply?" Mr. Rau asked. "It's what we can make available to meet our treated water demands," Mr. Bode explained. "That's the key driver in all of this. We need to determine how many people we can serve with our existing supply system." "Does that take into account our ability to store water," Mr. Rau continued. "That's right, storage is a big factor in safe average annual demand, because you can carry it over from year to year," Mr. Weiss answered. Modeling Assumptions Mr. Weiss listed some of the assumptions they use when modeling: • Population and water rights held constant for each 30 year run • CBT quota used for the critical year is 50% - He commented that this is rather conservative, but that's what an earlier modeling effort used, so staff stayed with it. • Only CBT portions of the North Poudre shares are used. • No Water Supply & Storage shares are used. They consider all of that to be rental water since it hasn't been changed for domestic use. • They are taking shares out of the various irrigation companies and dedicating some portion of that for raw water demands. David Lauer asked about the CBT portion of the North Poudre shares. Does that mean that you are cutting in half what we actually use at this time? Mr. Weiss explained that with each share of North Poudre, there are different types of water. A portion of that is CBT water and another Water Board Minutes • March 23, 2000 Page 7 portion is direct flow rights. At this point the direct flow water is only for ag. use. That hasn't been changed yet. "We are just using the CBT portion for treatment." Mr. Bode added that there are raw water sources that are being taken out for the raw water needs of the City. The next slide provided examples of supply variables: shares for treatment, total company shares, Fort Collins shares, raw water shares, rental water, shrink factor, number of CBT units per share, unavailable water, APOD prorata yield, RAW prorata yield and rental prorata yield. He then pointed out an example of the demand variables. He said they are basing it on population, and using gallon per capita day demands to generate our total demand. "We also have some contractual demands such as Anheuser-Busch (AB). We realized there were going to be some variations in some of those annual demands based on the type of water year we were having. We saw from the historical look, that there was a pretty strong correlation with increased demands with low virgin flow years. We developed a regression equation so we could get some kind of variation in our annual demands." Once all the input data was created, they imported it into the network simulation model. He next showed a graphical representation of what they have come up with for the City's safe average annual demand. The graph showed the demand in acre feet that we are able to treat. "We are looking at a future scenario in this model run. There is some annual variation, about plus or minus 8 or 9%. The dark blue portion on the graph was the water that comes from Horsetooth that we are able to treat. The light blue was the water they were able to take off the River. The surplus water from direct flow rights was shown in yellow. That is water that they were unable to store or there wasn't a demand for at that point. The demand just gets to the level of our total supplies in the critical year. The bars at the bottom represent our end of year storage contents. In this example, we were using a 10,000 ac-ft pool to store Southside Ditch water. That pool could possibly be in Halligan, gravel pit storage or some other spot. That stays pretty steady, and then we get to the critical year and we pull out water in storage to meet the demand. This takes into account, the 1-in-50 drought. The drought begins in the year `19 and runs through the year `24. In year `24, we only have a 50% quota. That's why in that year, we have to take all the water out of storage. "In light of all the new information coming out about Horsetooth Reservoir," Tom Sanders asked, "how is it going to affect us in those first 5 years. Is it going to be dramatic?" "It is our understanding that the Northern District expects to meet all the demands that are out there. We hope that doesn't change a lot," Mr. Bode responded. MY. Lauer asked Gene Schleiger if the water will just be flowing through the reservoir rather than being stored. "Right, we'll try to dedicate the full capacity to come in during the summer and try to keep it there," Mr. Schleiger explained. "We won't have the ability to bring in as much as we have going out." Mr. Weiss went on to describe the scenarios they looked at. For the service area and water rights descriptor they looked at two scenarios, one for the existing service area which was "A" and an enlarged service area that includes new growth in the urban growth area, which is `B". Water Board Minutes March 23, 2000 Page 8 They also looked at five facility descriptors: Existing facilities, pipeline capacity of 20.9 MGD New Pleasant Valley Pipeline (PVP), total capacity from Poudre River of 80 MGD. New PVP plus local active storage capacity of 2,000 ac-ft to store Southside Ditches water (SSD) New PVP plus 10,000 ac-ft of active storage capacity in Halligan Reservoir or other regional reservoirs to store Southside Ditches water New PVP plus 30,000 ac-ft of active storage capacity in an enlargement of Halligan Reservoir to store additional Poudre River water with only junior storage decrees. When you consider all of the different scenarios, we generated 100 different safe average annual demands. For the hydrologic periods, we looked at the 1-in-50 year and 1-in-100 year droughts. For population and water rights scenarios, we started in 1998 and jumped up in 10-year increments. With each increase from 1998 to the year 2030, we had new water rights coming in with new development. The next table showed the projected demands for the Utility service area versus safe average annual demands for various supply and facility scenarios for a 1-in-50 drought. The values on the left are projected populations and projected demands. The first column of values on the right side are safe average annual demands for each scenario. For example, the value in the year 2040, indicates that we would just be able to satisfy the demand for a 1-in-50 year drought for what the population would be at that point. With the 10,000 ac-ft of storage and an enlarged Halligan, there will be a good buffer for future years. With existing facilities, we would probably have a deficit in drought years. "Are you saying that we have to expand Halligan to have that buffer?" Dr. Sanders asked. "We either have to expand Halligan or find storage in some other location," Mr. Weiss replied. "In either case, it looks like we are going to need storage." Mr. Bode said that when you look at A-1, which is existing facilities, even though we are getting additional water rights, that yield does not increase very much. "If you look across 1998, you can see the effect those new facilities would have on the yield, and without any additional water rights." Paul Weiss continued by showing a slide with a graphical representation of the preceding table. Looking at the top line, although there is an increase in water rights and shares from different ditch companies, the actual yield doesn't increase that much. If you look on the vertical axis, all the scenarios are using the same number of shares of water rights, you can see, with the different facilities in place, the total increases are in safe average annual demand. The dark blue line is the projected treated water demand. He next showed the same hydrologic scenario, but this time including an increased service area. "We pick up the new growth in the Urban Growth Area." With new water rights coming in, the safe average annual demand has been increased by 2000 ac-ft. Once again, it becomes evident that we are going to need storage in future years. Water Board Minutes • • March 23, 2000 Page 9 You can see that the 2,000 ac-ft storage no longer satisfies our future demands at the year 2020. The next slide highlights the extremes for the year 1998 and the future year 2040. Using our conversion factors, that's what we expect our annual yield to be. With existing facilities the actual firm yield for treated demand is quite a lot less. The increased firm yield with the PVP and 10,000 ac-ft of storage vessel scenarios were also highlighted. The preceding set of slides was for a 1-in-50 drought. The next set of slides provided projections for a 1-in-100 year drought. Mr. Weiss noted, looking at the results, that typically with a 100- year drought, there is a decrease of about 4,000 ac-ft. for the safe average annual demand for almost all of the scenarios. With the 1-in-50 year drought, supplies for the 2,000, ac-ft storage scenario are good through the year 2020, but with the 1-in-100 year drought, it is 2016. "With an increased service area in the future, we need 10,000 ac-ft of storage somewhere to handle an extreme drought," he stressed. David Lauer pointed out that the estimate mentioned earlier for increased storage for Halligan was 30,000 ac-ft. Mr. Weiss pointed out the top line in a graph that called for 30,000, He also indicated another line for 10,000 ac-ft of storage. The next slide pointed out clearly that our existing facilities are inadequate in the future. Another graphic just showed the results of the scenario with the new PVP and 10,000 ac-ft of storage for the 1-in-50 and 1-in-100 year droughts for the existing service area. "If our service area never increases, that 10,000 ac-ft pool should service all our needs and still give us some protection," he concluded. However, if we take on an enlarged service area, we can see that the 10,000 ac-ft pool, in a 1-in-100 year drought, may not be enough. Effects of SSD Storage Mr. Weiss continued by saying that he wanted to emphasize the effects of Southside Ditch storage. The first slide compares 2 scenarios representing the year 2030. For one scenario he used no storage and the other he used 10,000 ac-ft of storage. "You can see that the safe average annual demand increases almost one-to-one with the storage that you provide. In the scenario without any storage we have a lot of surplus Southside ditch water that we are unable to treat because of timing of the SSD yields. Typically the largest yield comes in the month of June, and we're not able to use most of the water." The next graph highlighted the City's yields off the River. Mr. Weiss pointed out that there was a substantial yield in the month of June, yet our demands weren't that high. The light blue portion shows the usable amount off the River. He indicated a gap showing that the City has certain obligations for treated water that must come from Horsetooth. "What this shows is that we need to find some way to better utilize our June water." "How much is that?" Dr. Sanders asked. "About 5,000 ac-ft.," Mr. Weiss replied. Potential Water Supply Issues Dennis Bode presented this segment of the presentation. He said that the rising prices of CBT water have raised new issues regarding raw water requirements. There are also some storage questions we need to grapple with, in particular, the existing Halligan agreement. There are questions on existing supplies, such as the agricultural part of the North Poudre shares. We also Water Board Minutes March 23, 2000 Page 10 need to look at some options for our Water Supply & Storage Co. shares. An issue we may want to revisit, as part of an update of our Water Supply Policy, is the drought criteria. Mr. Bode briefly went over an outline of potential water supply issues: Water Supply for Municipal Use a. Raw Water Requirements (RWR) policy Changes in type of water we accept? Proportion of cash to water? How do we determine cash in -lieu -of rate? What do we buy with cash (water rights, infrastructure)? b. Storage How much storage do we need to manage our water? Halligan, Seaman, Gravel Pits, Horsetooth (SSD) other? Who do we cooperate with? What do we do with the Halligan Agreement? C. Use of existing supplies NPIC agriculture water — change of use, agricultural lease? WSSC — change of use, agricultural lease, exchange with W.D.? d. Drought criteria e. Water Conservation Regional Cooperation a. Tri-Districts (SCFP) b. WFCWD C. Greeley d. NCWCD — (PVP, NISP, SPWCP) e. Northern Regional Water Coalition f. Larimer-Weld Water Issues Group 3. Agricultural Economy and Open Space a. Do we promote, accommodate, discourage irrigated agriculture? b. WSSC shares — agricultural lease, change of use, trade for SSD supplies? C. NPIC shares — leases to agricultural users, change of use? d. Long-term water leases? Water Board Minutes • • March 23, 2000 Page 11 4. Quality of Water Sources Effect on water supply quantities 5. Minimum Flow and Ecosystem Protection Where? Who? Why? Alternatives? Cost? Effect on supplies? Recreational/Aesthetic Flows Where? Who? Why? Alternatives? Cost? Effect on supplies? What's Neat? Mr. Bode said that staff plans to do some additional evaluation, focusing more on some of the main issues. They will look at some of the alternatives and develop some pros and cons for each. Staff would also like to have some meetings with the Water Supply Committee to discuss the next steps. The Water Supply Committee needs to decide if this will be a joint effort with the Liaison Issues Committee. Tom Sanders thanked Mr. Bode and Mr. Weiss for the excellent presentation. "It's exactly what we need as a planning document," he said. He mentioned that the Engineering Committee would be interested in discussing the Halligan aspect, and perhaps some other technical aspects. Dr. Sanders asked if there were any further comments or questions. Mike Smith said one of the first items that has to be addressed is the Raw Water Requirements (RWR), not because of water supply issues, but because of their relationship with the surrounding districts. "There is currently a fairly serious problem occurring with CBT water. Most districts take mainly CBT water and the price of CBT has gone from $3-4000 to $16,000. They continue to raise their RWR for their cash -in -lieu -of. This has put a bind between the districts and the City," he stressed. Development is occurring on the City's boundary where the developers are concerned about the high RWR's for CBT water. The City's very modest RWR with our focus on SSD water is becoming a problem for the Districts. "Somehow we need to arrive at a unified position so we don't have this wide range," he contends. "Do you think the Water Supply Committee should be the one to work with on that issue?" Dr. Sanders asked. "It would be good to have either the Water Supply Committee or the Liaison Issues Committee, or the two committees combined," Mr. Smith responded. He added that he would request that they meet within the next 3-4 weeks. "Didn't we just raise the cash -in -lieu -of rate?" Dr. Sanders asked. "It is $3500 and went into effect January 1, 2000," Mr. Bode related. Water Board Minutes March 23, 2000 Page 12 Bill Fischer asked what CBT is going for now. "It goes for about $15-16,000," Mr. Bode replied. Mr. Fischer has heard of an asking price of $18,080. "Is that tending to draw development to the City?" Robert Ward asked. "Yes, it has a tendency to do that and they are trying to say that they want the City to serve the District which creates quite a contentious atmosphere." Mike Smith replied. Dr. Sanders asked staff to set up a committee meeting within the next couple of weeks, and bring the topic up for discussion at the April meeting. Paul Clopper asked if staff knows of any community in the Front Range that plans for a greater than 1-in-50 drought. "I think most of them are 1-in-50," Mr. Bode replied. Tom Brown asked what the effect of assuming that the portion of North Poudre and Water Supply & Storage water not used in the analysis was available for treatment. "Are the results the same because of lack of storage, or would making that water available in this simulation make a difference?" "It would make a difference," Mr. Bode replied. The estimate for using both of them might be an increase of 4,000 to 5,000 ac-ft, if all of those shares were changed over to municipal use. DOWNTOWN RIVER CORRIDOR IMPLEMENTATION PROGRAM Timothy Wilder, from the City's Advanced Planning Dept, said the purpose of the Downtown River Corridor Implementation Program is to coordinate existing projects and identify new projects for implementation in the area north of Riverside between North College and East Mulberry. He pointed out the boundaries of the project on a map. City staff has been working towards that end by holding meetings with property owners, organizations, and other interested citizens. Projects on the south side of the Poudre River were ranked according to the extensive feedback gained during the meetings. Some of what Mr. Wilder will be discussing relates to the Floodplains Regulations subject that Bob Smith will present today. Mr. Wilder explained that there are a number of reasons we are discussing this River Corridor plan, and one of those is that the City's Comprehensive Plan expressed a vision for this area. "We would like to try to implement that," he said. Coordinating existing projects down the Poudre corridor is very important, as well as addressing some of the issues such as street and stormwater deficiencies, etc. He said there has been a lot of interest from the community in this project, and that has been evident in some of the public meetings that have been held. The vision for this area is a mix of land uses, protecting the history where possible, enhancing the natural elements of the River, protecting the floodplain and permitting redevelopment in appropriate areas. The land uses have changed over time from the location of the old fort to present uses, including industrial and residential. However, the land use code allows some new uses, recognizing that uses may change over time. In contacts with the public there have been questions raised about how the City protects the River. The Land Use Code establishes natural resource buffers along the River. The City owns considerable open space adjacent to the River (about 1/3 of the area). Water Board Minutes . March 23, 2000 Page 13 There have also been questions about where development is allowed. "We are not talking about changing the possible land uses. What we are discussing are the various projects that can occur along the River corridor," he said. He displayed a map that showed the existing developed area. In some areas re -development could occur, primarily through private investment. He pointed out buffer areas along the River and floodplain areas. He also pointed out the Oxbow area, which the City is in negotiations to purchase. He stressed that there is not much opportunity for new development. He reiterated that, essentially, what the process has involved for the last couple of years is not to develop a new vision for this area, but to identify and try to implement the projects in the Downtown River Corridor, recognizing that we have many plans that have been adopted throughout the years. "We are trying to address the sense of frustration often expressed of "why aren't we ever doing anything about the existing problems and preparing for the future?" Mr. Wilder was brought in to try to provide guidance through the first stage of the process, which is to identify and prioritize projects in the corridor. The process began with a huge list of projects coming from various plans that were initiated through community feedback through the years. They first went through a filtering process that involved the community, City Council and other non -governmental organizations. Hundreds of people attended each of two meetings held last year in May and October. This allowed staff to filter down the projects to a reasonable number and start the prioritization process. Mr. Wilder included those projects, listed under first, second and third priority designations, in information he distributed to the Water Board. He emphasized that all the projects on the list are important. He then described some of the projects on the list. Mr. Wilder pointed out three areas that are in the floodway or floodplain. Decisions need to be made about what should be done with them. For the N. College/Vine Dr. area, the recommended option is to purchase properties from willing sellers, but without construction of a levy. He listed some pros and cons of the option. He pointed out that part of this was identified in the Drainageway Master Plan as well. Option two is the purchase option as well as the construction of a levy. "We are not recommending that at this time because of some of the costs associated with it," he explained. He said that stormwater could address some of the major issues related to this option. The third option is really a "do nothing" option. He pointed out that there are limited opportunities for redevelopment and remodeling, etc. He noted that all the areas he is talking about are consistent with the Stormwater Master Plan. In the "Triangle" area, south of Lincoln Ave., there are 6 or so privately owned properties which are in the 100-year floodplain. This project was not listed in the Stormwater Master Plan. Some of the properties are on the edge of the floodway. The first option, as before, was to purchase from willing sellers, which is currently the recommended option. Pros and cons are much the same as before. Option two was the "do nothing" option. He went on to another item, recently added. A red flag was raised at the Air Park that the Stormwater Master Plan contains a structural alternative for Lemay. "We need to add this project into the discussion, and it is something the Board needs to keep in mind," he said. Water Board Minutes March 23, 2000 Page 14 Mr. Wilder said that staff will be presenting recommendations to the City Council at a study session on April 1 la'. A final recommendation will be presented at a regular meeting of the Council on May 10h. After this phase of the project is completed, staff will continue coordination of existing projects to the area, and form an interdepartmental lead team to implement the projects. "We also need to do more project analysis, identify sources of funding, determine how much these projects will cost, and identify a timeline," he concluded. He then asked for comments and questions. He urged Board members to express their concerns and offer suggestions by letter or directly. Robert Ward commented that a lot of what has been presented about other issues, Mr. Wilder has just presented in a very graphic way. He assumes that out of Mr. Wilder's work with others, will come a quantification of some of the issues that are listed in the City's Water Supply plan. There will also be other things to consider. For example, if kayaking becomes an issue, it must be determined what flow will be needed in the Poudre, where that water will come from and what the timing will be. Of course the other element is floodplain issues. "There needs to be a constant connection," he stressed. "As you move toward quantification, there is going to have to be a tight dialogue over what your plans are relative to the ability to supply water, and the timing of that has some interesting implications," he concluded. David Lauer asked, "given the attention being given to the Oxbow Site, the 20 acres between Lincoln and Linden on the east bank of the River, why is it there is just one option?" The citizens of that area are not looking very favorably on an amphitheater, gardens and open space at this point. "Why aren't other options being considered for that area?" "There should be two options," Mr. Wilder replied. "The options for the owners are somewhat limited given the floodplain," he added. Mr. Wilder's understanding of the public purchase, is that the owners want to sell the property only for certain uses. "It will be up to the community and City Council to decide if those uses are acceptable," he stated. Dr. Sanders thanked Mr. Wilder for the presentation. He regretted that there wasn't more time to discuss some of the issues due to a lengthy agenda. POUDRE RIVER FLOODPLAIN REGULATIONS Bob Smith updated the Board on new information with regard to the floodplain regulations for the Poudre River. Staff met with City Council during a study session on March 14, 2000 and was scheduled to meet with them at another study session on April l la'. Between these meetings, staff will be conducting outreach on the issue, soliciting comments, recommendations, etc. from various boards, commissions, agencies, organizations and individuals. This feedback will be reported to City Council on April I Vh. This item is currently scheduled for formal City Council consideration on May 2, 2000, where it is anticipated they will take action on the matter. Staff emphasized that this issue will define the current and future levels of risk that we, as a community, are willing to live with. Staff believes the health and safety of our citizens is an important community value, and weighing that value with the rights and values of owners of Water Board Minutes March 23, 2000 Page 15 property located in the floodplain, is not an easy balance. This is not an issue where there is a clear right or wrong answer. Possible Conflict of Interest Paul Clopper and Dave Frick declared a possible conflict because they are both employed by Ayres & Associates, the firm that supplied some of the graphics in the presentation. Mr. Clopper didn't think there was any conflict, but he thought it was prudent to state it for the record. Chair Sanders agreed that there didn't appear to be a conflict. Background After the Flood of 1997, questions were raised concerning the adequacy of floodplain regulations in the City. A study was initiated to review the floodplain regulations for the Poudre River. The purpose of the study was to review the existing regulations and make recommendations as to whether those regulations should be revised. Bob Smith said the fundamental question is the level of protection the community is willing to live with concerning the hazards of flooding along the Poudre River corridor. Should regulations be tailored for the protection of property and the safety of residents for the 100-year flood which has a 1% chance of being exceeded in any given year, or for the 500-year flood which has a 0.2% chance of being exceeded in any given year? He then went through a summary of information that has been generated on this issue: When Mr. Smith talks to groups about flood protection, an important piece of the presentation is that for every dollar we spend on pre -disaster mitigation, we save $2.00 in the long run. History of Floods on the Poudre River The history of floods on the River and the comparison of those flows with the100-year design discharge of 13,300 cfs, was provided in the attachments. There have been three floods (1864, 1891 and 1904) that were greater than the 100-year discharge. Mr. Smith showed pictures of what occurred during those events. 100-Year F000dplain and F000dway Options Several criteria relating to the floodplain regulations for the Poudre River have been developed. These criteria were assembled into the following four options for changing the floodplain regulations. A matrix of the options was in Board packets with the attachments. The floodplain regulation options include various floodway widths and regulations criteria. The floodway options include the 0.5-foot rise floodway (existing regulations), the 0.1-foot rise floodway, and the option that the floodway equals the floodplain. In addition, the 500-year Product Corridor is combined with a 0.1-foot rise floodway to create another regulation option. Option A — Existing Regulations This option represents existing floodplain regulations for the Poudre River. Water Board Minutes March 23, 2000 Page 16 Option B — More restrictive than Existing Regulations This option represents criteria that are more restrictive than the existing floodplain regulations in Option A. The floodway width is determined by a rise in water surface elevation of 0.1-foot which creates a wider floodway compared to Option A. Option B-1— More restrictive than Option B Mr. Smith said the 4a' option called B-1 is new after the last Council study session. It is a combination of B and C. Many of Option B's criteria are combined with criteria for the 500-year Product Corridor as well as a few additional criteria. Similar to Option B, the floodway width is determined by a rise in water surface elevations of 0.1-foot; the floodway cannot be modified to allow development; capital projects are allowed to protect existing properties; the finished floor of structures must be 24 inches above the 100-year water surface elevation; access to a structures during flooding by emergency vehicles must be dry; residential developments, re -developments, and/or additions are not allowed in the floodway or in the floodplain; fill is not allowed in the floodway; mobile home parks are not allowed in the floodway or the floodplain; commercial developments, re -developments, and/or additions are allowed in the floodplain but not in the floodway; and facilities associated with public infrastructure, recreation, and natural resource uses are allowed in the floodway. 500-year Product Number Corridor Bill Fischer asked for a definition of the product corridor. Mr. Smith said you basically take the velocity times depth, and if you come up with a number 6 or larger, it will equal unsafe flow characteristics, which means that a person can't stand up in the flow. "It's really kind of a general rule of thumb," he acknowledged. "A lot of variables go into it." Attachment C delineates the corridor for the 500-year floodplain where the product number is equal to or greater than six. The 500-year floodplain is based on a discharge of 24,100 cfs. The 500-year Product Corridor is incorporated into the criteria in Option B-1. Option C — Most Restrictive This option represents criteria, which are more restrictive than the other options. Mr. Smith took the Board through several slides with maps showing where the floodways and floodplains are located, including the 500-year floodplain and floodway and the 500-year Product Corridor. He said the bottom line is going from a 6 inch to a 1/10th inch. You are adding 8 existing structures that are part of the regulations that must be dealt with as far as the impact to additional structures. Ratings The City is currently at a 6 rating which means that people who pay flood insurance get a 20% discount. With Option A, which we currently have, with the audit we will go to a 5 based on what we have in place. Water Board Minutes • March 23, 2000 Page 17 "The greatest potential for points is if you go to a B-1 or a C, where there is an actual acquisition program," Mr. Smith explained. Mr. Lauer asked what the rating would change to with Option B-1. "Gradually, the more property you buy, the more you progress up the rating curve chart. The idea is to remove structures and acquire more open space," Mr. Smith answered. "If you just stay as we are today, and don't have an acquisition program, you don't get any points, but by buying properties in the floodplain, you have a better chance for points. It depends on where you want to go," he added. Freeboard We add a couple of options there. FEMA doesn't recognize the 6 inches above the one -foot level. They round it to the nearest foot. This is with Option A. With Option B, we basically cut the cost in half. Regulations in Other Parts of the Country Mr. Smith presented some examples of regulations from several areas across the country. He pointed out that there is not a national database that provides regulations from all parts of the country. Recommendations from Water Board Due to a lack of time for a thorough discussion and recommendation, the Board decided to state some general recommendations for staff to put in the form of a memo, which they will include in City Council packets for the April 11`h study session. The Board will take formal action at their April 27, 2000 meeting. Below are some of the items that the Board authorized Bob Smith to convey to the Council: 500-Year Product Corridor vs. 100-year 0.1-Foot F000dway Using the 500-year design storm in the hazard definition and regulatory standard along with the 100-year regulatory 0.1-foot floodway for the Poudre River, is confusing. The Board would recommend that the City use consistent criteria. In addition, the "product corridor" concept is a rule of thumb criterion and will change as encroachments take place along the River corridor. On the other hand, the regulatory "floodway" criterion is a nationally accepted standard and is readily understood and universally used. In this particular case, however, because the 500-year product corridor and the 100-year regulatory 0.1-foot floodway are virtually identical, the same end result of option B-1 can be obtained without reference to the 500-year product corridor. This could be accomplished by using the "land use" criteria Council likes in Option B-1 along with the floodway definition of Option B. The Water Board strongly supports not considering further the product corridor concept in the regulations. Water Board Minutes March 23, 2000 Page 18 Technical Issues Concerning the Product Corridor Concept Should Council decide to use a product corridor method as a regulatory standard, the Water Board would recommend that staff and their consultant use a more accurate modeling technique. In simple terms, staff has used a one-dimensional model, which only provides approximate boundaries. To accurately define the product corridor for use in a regulatory manner, the Board would recommend staff use a two-dimensional model due to the complexity of the velocity distribution along the stream cross-section. Floodplain Vegetation As more and more of the open space along the River corridor is purchased as open lands, the Board is concerned about the vegetation in these areas. The Board would like to make the Council aware that vegetation, if left to grow naturally, or is planted unabated, can have the same effects as urbanization on flood elevations in the floodplain. Vegetation will restrict channel capacity, causing floodwaters to spread out over larger areas; thus, creating wider areas of flooding. Also, large vegetation can become floatable and plug bridges. Long-term maintenance programs should be undertaken to ensure the desired degree of vegetation along the River corridor. Bridge CapacitX Many people are injured and killed during floods when they try to navigate flooded streets and highways. Design criteria for bridges and roads along the River corridor should be enacted to ensure adequate capacity of these bridges and roads for the safe passage of flood flows from the 100-year event. The Water Board will take formal action on the Floodplain Regulations at their April 26, 2000 meeting. ADJOURNMENT The meeting was adjourned at 5:35 p.m. Due to the lateness of the hour, one agenda item, items under staff reports, committee reports and other business were not discussed. Some of the items will be discussed at the April meeting. Water Board S cretary