Leyden Creek Community

LEYDEN LAKE MEETING UPDATE

Apr 10, 1999

April 6, 1999 Community Meeting on Leyden Lake Reservoir

Short presentations were made by:
?¨ Jeanne Rossillon, Design and Review Engineer, Jefferson County
?¨ Dave Lloyd, Chief of Design and Construction, Urban Drainage and Flood Control District
?¨ Jack Byers, Assistant State Engineer, Division of Water Resources
State Engineer
The presentation and discussion with Jack Byers clarified the following points:
?¨ breaching the day will allow flows in an area that has been developing for the past 80 years
?¨ development currently exists in the spillway of the dam
?¨ State Engineer's position is that rainfall will not create as catastrophic event as allowing the dam to remain in an unsafe condition
?¨ breach plans for the dam have been approved by the State Engineer
?¨ State Engineer made a determination in 1988 that the dam had an inadequate spillway, and nothing was done until 1998 when the State Engineer decreed that the dam had to be repaired or breached
?¨ State Engineer has granted a one year extension to December 1999 with understanding that if the State Engineer does not see substantial progress in the next six months towards resolving the issues, the dam will be breached according to the approved breach plan
?¨ State Engineer's analysis is that the improvements needed include a substantial increase in the spillway (unless the dam height is lowered); repair of cracks and erosion; removal of trees growing in the dam; improving problems associated with seepage and maintenance
?¨ a 24" pipe is being installed to allow water flow to occur now

Urban Drainage and Flood Control District
The presentation and discussion with Dave Lloyd of Urban Drainage and Flood Control District (UDFCD) clarified the following points:
?¨ the dam is an irrigation and storm water detention facility
?¨ UDFCD and City of Arvada conducted studies in the 90's to identify alternatives for the dam
?¨ UDFCD and City of Arvada explored lowering the dam to maintain a permanent pool of water and use the dam for storm water storage only
?¨ an appraisal of the 93 acres of land as it currently exists resulted in an estimated value of $300,000
?¨ UDFCD and the City of Arvada asked Farmers Highline to donate 56 of the 93 acres to allow the City and Urban Drainage to repair the dam. Farmers Highline never responded
?¨ City of Arvada and Jefferson County rely on volunteers to implement their emergency preparedness plans and residents are concerned about the ability to respond to emergencies swiftly with volunteers
?¨ the master drainage plan recommends six 6x10 culverts be installed under Alkire and residents expressed concern with nothing being planned for east of Alkire because flooding water will not stop flowing at Alkire
?¨ preference is to work with the existing land conditions rather than dig out the silt because it is extremely difficult to work with
?¨ all options for saving the dam involve lowering the dam to take the reservoir out of the state jurisdiction (state jurisdiction includes all dams over 10' in height or holding more than 100 acre feet of water
?¨ UDFCD will involve residents in the design phase of the dam and requested names and addresses of everyone in attendance

Jefferson County
The presentation and discussion with Jeanne Rossillon, Design and Review Engineer, Jefferson County clarified the following points:
?¨ negotiations have been and continue to be conducted by County Administrator Ron Holliday with the City Manager of Westminster (Jeanne could not report on the status of the negotiations because it had been two weeks since she last talked with Ron Holliday
?¨ Jefferson County's priorities are to acquire the full 93 acres of property with the remainder not used for the dam to be used for open space purposes

Community Comment
Carol O'Dowd, facilitated the discussion with the 40 residents who own property either below or adjacent to the dam. During the discussion, the residents developed the comments outlined below.

Poor Communication with Jefferson County
An important point that residents want addressed is the current lack of responsiveness by Jefferson County Commissioners. Several residents have placed calls to Commissioners and have never received a response. Others noted concern that Jefferson County sent an employee who could not report on the status of negotiations. Some general observations were:
?¨ Jefferson County Commissioners should represent County residents interests
?¨ Jefferson County could condemn the land to acquire the reservoir, but Jefferson County wants to avoid that option
?¨ Jefferson County will respond to breaching because it will enlarge the flood plain area and permits such as 404 and FEMA are required
Property Damage Anticipated with Pipe Installation
?¨ installation of the 24" pipe will be completed in next 3 or 4 weeks and water will then flow into what was Ledyen Creek drainage; the pipe will transmit water and sediment
?¨ wells have gone dry after the water was released from the Reservoir (State Engineer explained that wells dependent upon seepage will go dry and well going dry is not responsibility of reservoir owner or operator
?¨ Jefferson County should take legal action to stop release of water into drainage area

Assessment and Data Needed Prior to Pipe Installation
?¨ Jefferson County should conduct some kind of legal assessment on what the results will be when returning water flow to a stream that has not been used in for 90 years and has development encroachment in the former drainage basin
?¨ no testing of the water quality has been done
?¨ study of how new water flows will impact water table, septic systems, current development, etc. should be done prior to completing the installation of the 24" pipe
?¨ residents requested other dams and spillways that were constructed in close proximity to existing homes; examples given included Lena Gulch on Youngfield between 15th and 16th, Greenwood Gulch south of Ken Karyl between Carr and Allison
?¨ What happens if Jefferson County does not act and water with sediment is released? How fast will water flow through pipe in a storm and pressure is added to regular water flow?

Preserve Community Character
?¨ no interest by anyone in seeing concrete channel improvements in the Leyden Creek Community area
?¨ residents expressed interest in maintaining existing wetlands