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HomeMy WebLinkAbout5.a. Rosemount Storm Damage ReportCITY OF ROSEMOUNT EXECUTIVE SUMMARY FOR ACTION CITY COUNCIL MEETING DATE: JULY 18, 2000 t AGENDA: ROSEMOUNT STORM DAMAGE REPORT AGENDA SECTION: DEPT. HEADS REPORT PREPARED BY: THOMAS D. BURT, CITY ADMINISTRATOR AGENDA NO: 5.A. ATTACHMENTS: MEMOS, EVERMOOR STORMWATER APPROVED BY: REVIEW Attached are the current reports from each department concerning storm damage in the City of Rosemount. FEMA requests separate claim reports for each site, including labor. McAndrews Road has been open to traffic since Sunday. Hawkins Pond pumping will probably be completed by Tuesday, July 18. Fahey Avenue will remain closed for about ten days. WSB & Associates, Inc. reviewed the Evermoor Development Area Stormwater System as it relates to the design in view of the recent 11 inches of rain received in a few hours. WSB reviewed the Comprehensive Stormwater Management Plan and the Westwood Professional Services Evermoor analysis for conformance with reasonable engineering design methods. They were found to be acceptable from the City's stormwater management philosophy, as well as sound engineering principles. Rosemount is uniquely challenged because of the number of landlocked basins it has. The City has started to implement the stormwater plan to develop outlets from some of the landlocked basins, and plans to continue that process as development occurs. The City is currently requiring positive overland overflows and adequate separation for basement floors above the pond high water levels to minimize the potential of residential and commercial flooding. RECOMMENDED ACTION: Informational only. COUNCIL ACTION: MEMORANDUM DATE: JULY 17, 2000 TO: TOM BURT, CITY ADMINISTRATOR FROM: DAN FICK, CITY ENGINEER/PUBLIC WORKS DIRECTOR SUBJECT: STORM CLEAN -UP While the major storm related work is nearing completion, significant minor work remains to be done. Summarized below is the status of the major storm damage sites. FAHEY AVENUE — Contracted repair work is scheduled to begin this week and cost about $15,000 to complete. Fahey Avenue will remain closed for approximately ten days. HAWKINS POND — Repair of the sanitary lift station and pumping of the pond are anticipated to be completed on Tuesday, July 18, 2000. CSAH 38/McANDREWS ROAD — McAndrews Road was opened to traffic on Sunday, July 16, 2000. Pumping started on Thursday, July 13, 2000 and is now complete. Pumping of the pond near the Marcotte residence started on Monday, July 17, 2000 and is anticipated to last for two days. With completion of the major repair projects, the focus now changes to the minor areas. A complete damage assessment survey has yet to be completed and we are aware of erosion damage to the Erickson Pond area. To -date, the total storm damage born by the City has been estimated at $500,000. Dakota County, however, will attempt to use State Aid disaster funds to pay for the pumping of McAndrews Road. TO: Tom Burt, City Admin. FROM: Scott Aker, Fire Chief RE: Storm Impact on Fire Department DATE: 7112/2000 During the weekend storm the Fire Department responded to six(6) calls. Three(3) of those calls could be attributed directly to the storm. Power Lines Down - - -(2 Calls) 17 Firefighters 35.75 Hours Sand Bagging - - -(1 Call) 15 Firefighters 107.5 Hours Lakeville Fire - - -- Mutual Aid MEMORANDUM TO: Tom Burt, City Administrator FROM: Dan Schultz, Parks and Recreation Director DATE: June 12, 2000 RE: Impact of storms and high water from July 7 and 8 of 2000 The storms and high water did not have a significant impact on the parks and trails system throughout the city. The visible damage in the parks includes a few downed trees, minor wash out areas of gravel, ag -lime and new sod. Also due to the water being pumped from Hawkins Pond into Twin Puddles Park, the park will be temporarily taken offline and scheduled activities will be relocated to another park. The Community Center had some water enter the building with no permanent damage. The electronic reader sign has been out of commission since approximately 10:00 am on Saturday, July 8, 2000. It will take one week before a repair crew can come out and determine if the problems are related to the weekend storms. MEMORANDUM TO: Dan Fick, Public Works Director Cindy Dorniden, Public Works Secretary FROM: Gary D. Kalstabakken Chief of Police/Emergency Manager DATE: July 11, 2000 SUBJECT: Documentation of Storm Work It appears that there will be a presidential declaration of Dakota County as a disaster area as a result of the rains and flooding of July 7 and 8. In order to ensure reimbursement for eligible expenses, it is important that all storm related costs are tracked from the start. Attached are forms from Federal Emergency Management that were used following the 1998 storms. Please utilize these forms to document expenses as they occur for this storm, too. A meeting for eligible cities will be held in the next week or two, if the forms have changed I will get you the new forms to use. When tracking expenses each separate job site requires its own paper work. FEMA recommends that a separate file be started immediately for each job site. Then the appropriate forms are completed for each site separately. The sites that I am aware of include: 1. Hawkins Pond/Lift Station 2. Fahey Avenue 3. McAndrews Road and Shannon Parkway 4. Rural Residential - Gravel Roadways (Although this encompasses several roads throughout the city I suggest this be tracked as one project at this time pending FEMA approval) 5. Debris Clearance When completing the paperwork, each worker's time must be attributed to a specific project. For example, if AJ worked 6 hours at Hawkins Pond and 2 hours at McAndrews/Shannon, he must be listed in the file for both sites' Labor Record. In order to track expenses other than labor costs more easily, the code for all purchase orders related to the storm should be coded under line item 101 4XXXX 01 439. If you have any questions, please check with me. Cc Tom Burt Jeff May JUL -18 -2000 14 18 WSB & Associates, Inc. WSB 8 ASSOCIATES INC. 8441 Wayzata Boulevard, Suite 350 Minneapolis, MN 55426 tel: 763 -541 -4800 fax: 763 - 541 -1700 To: Ms. Alysox Morris, Water Resource Engineer City of Rosemount From: Bret A. Weiss, P.E. WSB & Associates, Inc. Date: July 18, 2000 Re: Evermoor Development Area Stormwater System WSB Project No. 1005-140 7635411700 P.02i08 B.A. Miaelueedt. P.E Bret A. Weiss, P.B. Peter R. Wilknbtin& P.B. Donald W. Sterna. RE Ronald B. Stay, P.E. Memerandum I am writing this memorandum to address the public comments regarding stormwater issues from the recent heavy rainfall that were presented to the City at the July 11 Planning Commission meeting. Many of the comments were directed to the Evermoor area, however, some were general in nature. Backeround The Evermoor development area and Birger Pond drainage district encompasses approximately 500 and 1,000 acres, respectively. The Evermoor subdivision is completely contained within the Birger Pond drainage boundary. A hydrologic analysis of the Birger Pond drainage district has been undertaken over the past years by the City and other consultants, and has most recently been studied as a part of the development of the Rosemount Comprehensive Stormwater Plan. This Comprehensive Stormwater Management Plan was prepared by Bonestroo, Rosene, Anderlik and Associates, a consulting firm hired by the City of Rosemount. During the review of the preliminary plat for the Evermoor subdivision, the developer's engineer, Westwood Professional Services, re- analyzed the actual stormwater conditions in this area with regard to ponding and storm sewer construction as they related to their development. WSB & Associates, as a reviewing agent for the City ofRosemount, reviewed both the Bonestroo Comprehensive Stormwater Management Plan and the Westwood Professional Services Evermoor analysis for conformance with reasonable engineering design methods. Many comments were addressed back and forth between Westwood and WSB to arrive at a system which we perceive to be acceptable from the City's stormwater management philosophy, as well as sound engineering principles. Simultaneous to the development of the Evermoor preliminary plat, the Birger Pond lift station and forcemain project was initiated. This project incorporated the development of a five cubic foot per second (cfs) pump outlet from Birger Pond along Diamond Path to Wensmann Pond. From that point, Wensmann Pond would discharge into Shannon Pond which is located at the corner of 160" Street and Shannon Parkway through an existing outlet. Shannon Pond is currently a large sand bottom, Iandlocked basin with no outlet. In the future, it is anticipated that this pond will discharge to Apple Valley or Minneapolis 9 St. Cloud 14fra0metum Engineers Plannerr P,iwrwnYv"54"nm&*. nw EQUAL OPPORTUNITY EMPLOYER JIJL -18 -2000 14:1e WSB & ASSOCIATES INC. ?635411 ?00 P.03/o8- Ms. Alyson Morris Water Resource Engineer City of Rosemount July 18, 2000 Page 2 possibly, easterly to the Mississippi River, however, at this time, the pond is able to utilize evaporation and infiltration. The City of Rosemount is uniquely challenged in the development of stormwater ponding facilities and corresponding outlets due to the presence of pothole ponding areas intermixed with flat topography. The development area is located on the west side of town with the Minnesota River located on the far eastern border. The development ofpositive gravity outfalls for the development area is very difficult to achieve and results in the creation of many landlocked basins. The City has started to implement the stormwater plan to develop outlets from some of the landlocked basins, and plans to continue that process as development occurs. The City is currently requiring positive overland overflows and adequate separation for basement floors above the pond high water levels to minimi the potential of residential and commercial flooding. Response to Questions We would offer the following responses to questions that were addressed at the July 11, 2000 Planning Commission meeting: 1. Question: Are the stormwater ponds for the project adequate? The common concern was that the undeveloped site was flooded and creating problems for the Marcottes. Response: The Evermoor site is currently undergoing grading operations along the west side of Shannon Parkway and is in the initial stages of that grading operation. Many of the proposed ponding areas have not been created to date due to the early stage of the grading operation. The completion of grading and development ofthe site will actually reduce the number of acres draining to the Marcotte Pond. The grading that has been completed to date actually reduced the amount of storm water discharging to the Marootte Pond through the creation of a new pond, which further accentuates how much storm water actually fell on the site during this storm. 2. Question: Why can't the lift station at Mamotte Pond be installed during the Phase 1 improvements? There is a problem there now, and future development will further the problem. Response: Originally, the forcemain piping system from the proposed lift station was intended to be extended through the northern portion of the Evermoor development site. Since that area will not be developed in the year 2000, (only grading operations occurring), it did not make sense to design the pipe to be placed in that location. Further, it is not anticipated with the minimal amount of development that will be able to occur in the year 2000, that any significant FitWPW M1W5-.r M77JW -& .wpf JUL -18 -2000 14:19 Ms. Atyson Morris Water Resource Engineer City of Rosemount July 18, 2000 Page 3 WSB 8 ASSOCIATES INC. ?635411 ?00 P.04i08 increase in drainage to the Marcotte Pond would occur. Because of the significant rainfall event, we are in the process of evaluating the installation of the forcemain and the design of the lift Station to install those improvements yet this year. 3. Question: Is the Birger Pond Lift Station adequate to accommodate the inflows to the pond? The pumps were turned offon Saturday because Wensmann Pond, a downstream outlet was very high. Response: As was discussed earlier, the Birger Pond lift station was designed to pump directly into Wensmann Pond without creating issues for the Wensmann Pond residents. However, it is the City's discretion to shut down the lift station if the Wensmann Pond elevation is high and the maj ority of the water has been pumped out of Birger Pond. The storage volume within Birger Pond is extensive and is not likely to be fully utilized until the entire drainage district area is developed, including the installation of additional storm sewer connections from areas southeast and. north of Birger Pond The installed outlet of 5 cfs is so small compared to the amount of water discharging to Birger Pond that shutting down the pump for a short period of time will not have a significant affect on the high water elevation. We do not anticipate that the pond will reach the high water elevation for many years into the future. 4. Question: Why aren't storm sewer systems designed to handle events as large as last weekend? In the past thirteen years we have had several storms that exceed the 100 -year design flood. Response: As can be seen from the attached information, this storm in the Rosemount area was extremely large and uncharacteristic of even the anticipated 1 % chance of occurrence rainfall events. There has been much effort put into the cost effectiveness of designing a storm sewer system for different rainfall events. Typically, the storm sewer systems in streets are designed to accommodate a 10- year retum frequency event storm, which is necessary in order to allow for safe passage on our roads and highways. It was further determined that ponds and storage facilities could be constructed within a reasonable cost to accommodate runoff from the 100 -year critical event storm without a structural inundation. This design storm is the design standard for almost all cities in Minnesota. F:iwrwmuo�sano�l�ea....� JUL -18 -2000 14 =19 WSB & ASSOCIATES INC. ?635411 ?00 P.05i08 M& Alyson Morris Water Resource Engineer City of Rosemount July 18, 2000 Page 4 S. Question: Does the removal of the vegetation generate more runoff to the Marcotte property? Response: It is true that removal of vegetation can increase the runoff rate to ponding areas due to reducing the amount of wetting and absorption from the plant materials. However, other factors such as soil compaction, roughness of the soil surface, time since it last rained and other factors would likely play a greater role. It is unlikely the removal of vegetation was a significant factor in exacerbating the problems experienced. bbalnm F.iWr!/7Ml NS.J�I071 wr/ JUL -18 -2000 14 :19 WSB & ASSOCIATES INC. ?635411 ?00 P.06/08 RAINFALL IN MINNEAPOLIS -ST. PAUL METROPOLffAN AREA FOR DURATIONS FROM 30 MINUTES TO 24 HOURS AND CHANCES OF OCCURRENCE PER YEAR RANGING FROM I% TO 99% Data Taken from U.S. Department of Commerce - Weather Bureau Technical Paper No. 40 - Dated May, 1961 Chance of 24-;Hour 12 -Hour 6-Hour > 3 -Hour 2 -Hour 1 -Hour 30 Minutes Occurrence 99+% 2.3 2.0 1.7 1.5 1.4 1.2 0.9 50% 2.8 2.4 2.1 1.9 1.7 1.4 1.1 20 °/u 3.6 3.1 2.7 2.3 2.2 1.8 1 A 10 % 4.2 3.7 3.1 2.6 2.5 2.1 1.7 4 % 4.6 4.2 3.5 3.0 2.8 2.3 1.9 2% 5.3 4.6 4.0 3.4 3.1 2.7 2.1 1 %0 5.9 5.0 4.4 3.8 3.5 2.9 2.4. Cky of & ringholty WSB Project No. 106S.11 Page 9 O O .R I 7L m rm z OT 2� m co O (7) ' z I Y� cn cn N OD :0 A� �D r D= r 0 m 0 ch T O z c m < m .m m 0 n C- 0 M N. �A BOILS ' d Ok, I T PSM S31U I DCSSU '8 HSM 6 T : t? T 000e -t3 T -int JUL -18 -2000 14:19 WSB B ASSOCIATES INC. Torrential Rains Douse South Metro - July 7-10, 2000 7635411700 P.08i08 rage i ui c Torrential Rains Douse South Metro July 7 -10, 2000 Torrential rains fell upon the Twinc Cities metropolitan area during the wakend of July 7 10. The spate of severe weather begin during the morning of Friday, July 7 when severe storms rumbled through the east metro. tigh winds, hail, and possible tornadoes led to significant property damage. The south metro, specifically fl a city of Eagan, received an extraordinary amount of precipitation later on the 7th, and during the ealdymorning hours of Saturday, July 8. Over eight inches of rain fell in a three to five hour span amss a small area of northern Dakota county. The climatological probability of receiving eight inches of rain in a five hour period for a given location in the metropolitan area, in a givenyM is far less than 9 s 7 6 a 4 Z s 1 0 inches Prepared by: Stale Climatology Ot6ce. DNR• Waters Data provided by: Dakota Sol and Water Conservation District Metmpol'aan Mosquho Control District An additional two to three inches of rain drenched National Weather S ervice already sodden neighborhoods during the evening of July 8 and the early morning of Sunday, July 9. Light rainfall fell again late in the late evening of July 9 and the early morning hours of Monday, July 10. The highest reported weekend rainfall total was 11.33 inches in soutl>tean,Eagan. The heavy rains led to extensive damage in some south metro communities. Serious urban flooding was commonplace, and severe erosion was reported in many areas. One life was lost in a flood - related incident. W SI radar- based-_R i JLita emo -Jul 3 WSI .bra based precipitation estimate - July. 9 WSl r b.StS.qd...Prc?.pata#io� ._ July, 10 (revised 7 111/00) Y Return to the Climate Journal m4wb;soils.uttm.edu URL: hnp: / /elinwc =u.cftId odownslifflub . Last modified: July 11. 2000 n1­6_ — i1 « «.i.1CM A^f1A UA.— T ^ '7111If%A Rainfall Totals n(5( M 4 .. If You Suffered Damage From The June -July Floods You May Be Eligible For State, and Federal Disaster Assistance You may be eligible to receive FEMA and State benefits if you live in Dakota,. Fillmore, Houston, and Mower Counties which received a Presidential disaster declaration. If you have insurance coverage, but still have unmet disaster - related needs, you may also be eligible. Assistance that may be available includes: * Disaster Housing Grants to cover temporary rent or make essential repairs to your home. * U.S. Small Business Administration loans to repair homes, replace personal property and assist businesses. * Grants for serious needs not met by other programs. To receive assistance available under the Presidential Disaster Declaration, you need to apply. This may be done by calling: Toll-Free Teleregistration .1(800) 462 -9029 For those who use TDD:1(800) 462 -7585 These numbers are open from 8 a.m. to 6 p.m. daily. Before you register, it is helpful to have the following information ready: * Your current phone number and address * Your address at the time of the disaster * Your Social Security number * A list of damages and losses you suffered * Good directions to the location of the damaged property * The name of your insurance company and your policy number If you have insurance, please call your agent prior to maldng application. (Please see reverse side for information about disaster assistance programs) DISASTER ASSISTANCE PROGRAM INFORMATION S .. Individuals and small businesses who suffered damages may be eligible for as_ sistance from:- °FEMA, .y other federal 'agencies,' State of Minnesota, and voluntary agencies. The assistance` programs are available to those located in Dakota; Fillmore, Huston and Mower Counties which have been "designated as major disaster areas by President Clinton. Federal Emergency Management Agency Programs DISASTER HOUSING ASSISTANCE: Housing assistance to individuals and families whose permanent homes were damaged or destroyed by the storm or flood. Types of aid include grants for: (1) alternate rental housing; (2) emergency repairs needed to make a residence habitable; and (3) mortgage or rental assistance in cases where the disaster has caused extreme economic hardship. Funds are also available for mitigation measures to minimize the effects of future disasters. INDIVIDUAL AND FAMILY GRANT PROGRAM: Provides grants to individuals and. families to meet serious disaster- related needs and necessary expenses not covered by insurance or other federal, state or voluntary agency disaster assistance programs. DISASTER UNEMPLOYMENT ASSISTANCE: Provides weekly benefits to those individuals out of work due to the disaster, including self - employed persons, farm owners, and others not covered under regular unemployment benefits. Small Business Administration Programs HOME/PERSONAL PROPERTY DISASTER LOANS: Disaster loans to homeowners and renters for restoring or replacing underinsured or uninsured disaster - damaged real and personal property are available in the declared county. Funds are also available for mitigation measures to minimize the effects of future disasters. BUSINESS DISASTER LOANS: Disaster loans to repair or replace destroyed or damaged business facilities, inventory, machinery, equipment, etc., not covered by insurance. These loans are available to large and small businesses in the declared county. Loans also may be available only to small businesses for working capital to assist them during the disaster recovery period. These loans are available in declared and contiguous counties. Other Agency Programs TAX ASSISTANCE: Federal: The Internal Revenue Service (IRS) allows underinsured or uninsured casualty losses that were suffered on home, personal property and household goods to be deducted on income tax returns. Amended returns may be filed for a previous year's filing so that disaster victims can receive a tax refund. Call the IRS at 1 800 829 -1040. FARM ASSISTANCE: Emergency loans or grants to farmers who were operating and managing a farm at the time of the disaster. Loans are limited to the amount necessary to compensate for actual losses to essential property and/or production capacity. i July 18, 2000 Mayor Busho and City Council Members City of Rosemount 2875 145` St W Rosemount, MN 55068 Dear Mayor Busho and City Council Members, In view of the recent rains and the damage and expenses that homeowners and the city had to endure because of the storm sewer run off and the flooding of holding ponds, we are asking the city and their consulting engineers from WSB to review the studies and ensure that there is sufficient capacity to hold the water, or in the case of our pond, that the lift station pump gets put in before any further development occurs on the Kelley Trust property. We also want to be sure that there is sufficient capacity in these ponds to hold the water without causing damage to homes, trees, and surrounding property. We would like to be assured that sufficient study has been completed to understand the volume and capacity of the locations that these ponds are being "lifted to" so we are assured that during a heavy rainfall, the pumps will remain on and not be shut down. We understand that the Birger Pond pumping was shut down during the rains on July 8 -9, 2000 and much of the Kelley property, plus our pond's lift station are scheduled to go to the Birger Pond. Who has the authority to shut these pumps down during a heavy rain? What is the documented process they use to make the decision to shut a pump down? We think you should reexamine the hydrologist report so you fully understand the amount of water that will run off into ponds from any new development. Are these holding ponds really designed to hold the necessary runoff that comes with homes, driveways, roads, etc? This should not be based on old hundred - year -old flood statistics. It seems to rain like this every few years. We had the "Super Flood" in 1987 and that was just 13 years ago. There should be a cushion of capacity in the ponds for the unusual rains that seem to be coming more often. The design diverts water and then assumes lift stations can take the water and move it to a "safer" area. There is the potential for loss of electricity during these storms and lift stations not functioning during this period. What arrangements does the city have to get back up generators to these ponds? The nine -inch rain from July 7, 2000 and the flooding of the homes around Hawkins pond shows how quickly water can rise when the area all around it has been developed. We need to insure that this does not happen to anyone else. Let's take the time right now to learn from some of our flooding and that of our neighbors in Eagan. We need to look at the density issue very closely and how it relates to runoff. If the reports look flawed, let's fix things before we go any further. We are enclosing a copy of a letter that we gave to the city and developer on Monday, July 10, 2000 to try to get resolution to our already existing problem and a copy of the letter that we gave to the members of the Planning Commission on July 11, 2000. Thank you for your careful consideration on this. Sincerely, Ken and Faye Marcotte 12931 Shannon Parkway Rosemount, MN 55068 651 -423 -5024 fax: 651- 322 -5584 email: kmarcotte@auswest.net July 4, 2000 Homer Tompkins Tom Burt Contractor Property Developers Company City Administrator 7100 Northland Circle Ste 108 City of Rosemount Minneapolis, MN 55428 Rosemount, MN 55068 This is a formal notice that we have an eminent problem relating to the run off from the Evermoor (Kelley Trust) Development directly south of our home. We are expecting an immediate resolution to this problem and you will be held accountable for any damages that we are receiving. We believe a lift station should have been put in our pond before the earth was disturbed and the grading started on the property. We had this discussion with the city on many occasions because of our concerns that our pond would not accommodate any additional water and they assured us that a lift station was going in. Homer Tompkins' excavator advised him that they had not disturbed anything that should cause run off to our land. He advised him incorrectly. We have video showing the run off and wash outs coming down the hill to our property and it is coming directly from the new basins that were created that are overflowing and flowing down the hill directly into our pond. You can see all the brown sand and dirt in the water of our pond all along the back third of it. It has washed right through the silt fence. It has also caused our pond to go well beyond the water easement and it has flooded our yard and also the protected wetland behind our home. The storm drain had water rushing through it fifteen hours - after the rains had stopped. tonig e h I expect Nwe help gandbagging on f our h and it is raining agar Monday to keep it out of our home. We were advised that you could get a pump but did not have enough hose to divert the water. We suggest using PVC and pumping it up over the hill to flow towards Berger Pond. We need immediate pumping to save irreplaceable one hundred year old oak trees that are under water, plus extensive landscaping, and hopefully keep the water from getting into our home and ruining things. We also request that you immediately check t h e new basins to make sure they are not weakened; because if they give way, we will have an immediate wall of water and we wont have time to� sand ho back the runoff from the city to block the storm drain and sandbag it by th that area. We would also like both the developer and the city to get the lift station in before any further grading is done. We also suggest looking at the design to make sure it is engineered correctly so the retention ponds hold the water on the property and that they can accommodate rains like we had the last few days without flooding the homes that will be built around them or the surrounding properties. The city should not have to spend the weekend sandbagging and pumping out homes. Thank you for your immediate response to this problem. A L , Mfait c:v f fC_ Ken and Faye Marcotte 07 11-- OOA11 :23 RCVD July 11, 2000 Planning Commission City of Rosemount 2875 145' St W Rosemount, MN 55058 07- 11- 00A11 :23 RCVD 07- 11 -00A11 3 Dear Commissioners, We are sending this letter because Ken is out of town on business and Faye has a business meeting that may make her late for the public hearing on the proposed design changes to the Evermoor (Kelley Trust) Development. Before an agreement is entered into to separate units, increase units, and build a larger association building, we think you should reexamine the hydrologist report so you fully understand the amount of water that will run off into ponds from this development. Are these holding ponds really designed to hold the necessary runoff that comes with homes, driveways, roads, etc? This should not be based on old hundred - year -old flood statistics. It seems to rain like this every few years. We had the "Super Flood" in 1987 and that was just 13 years ago. There should be a cushion of capacity in the ponds for the unusual rains that seem to be coming more often. The design diverts water and then assumes lift stations can take the water and move it to a "safer" area. There is the potential for loss of electricity during these storms and lift stations not functioning during this period. What arrangements does the city have to get back up generators to these ponds? The nine -inch rain from July 7, 2000 and the flooding of the homes around Hawkins pond shows how quickly water can rise when the area all around it has been developed. We need to insure that this does not happen to anyone else. We have a water retention pond on our property that also is an example of more run off than these ponds were designed to hold. We have water corning into the pond from the storm sewers and also coming down the hill from the Kelly property. It has gone well beyond the city easement and has flooded extensive landscaping and irreplaceable one - hundred- year -old oak trees. This is before any homes, driveways, and streets have been built. We have been told that the ponds over by Shannon Park Elementary flow into our pond. This appears to be close to the area that is requesting additional units and a larger building. How will this retention pond handle that runoff? Right now the city is trying to find a pump and hose large enough to get the water out of our back yard and back into the easement. In the meantime, we have lost landscaping and we risk losing these valuable trees and further rains will result in damage to our home. We thought much foresight and planning went into these developments to protect our valuable environment. Let's take the time right now to learn from some of our flooding and that of our neighbors in Eagan. We need to look at the density issue very closely and how it relates to runoff. Don't approve more units until we are certain we can adequately handle what already is planned. If the reports look flawed, let's fix things before we go any further. e We are enclosing a copy of a letter that we gave to the city and developer earlier on Monday, July 10, 2000 to try to get resolution to our already existing problem. Even though the city knew about our flooding as early as Saturday morning, they have been unable to get a pump and hose to our property yet to start the pumping operation. This shows that it is not a quick fix to even locate pumps during times like this. We need to do very careful planning so we learn from these situations and prevent them in the future. We should cease all activity until we have done a reevaluation of the size of the ponds so that everyone is assured that the Kelley property will hold all its runoff on its property without damaging existing homes and property or future homes to be built. We're certain you don't want another Hawkin's pond issue. Thank you for your careful consideration on this. Sincerely, 1�e /a i2n e jCZz l� Ga Ken and Faye Marcotte 12931 Shannon Parkway Rosemount, MN 55068 651- 423 -5024 fax: 651 - 3225584 email: kmarcotte(�rt�uswest.net 0 - ODA11:23 RCVD