City Council (View All)
Monday, March 14, 2011
MINUTES FOR THE STUDY SESSION
ASHLAND CITY COUNCIL
Monday, March 14, 2011
Siskiyou Room, 51 Winburn Way
Mayor Stromberg called the meeting to order at 5:32 p.m. in the Siskiyou Room.
Councilor Chapman, Silbiger, Lemhouse, Morris, and Voisin were present. Councilor Slattery was absent.
The Look Ahead agenda item was moved to number 2. on the agenda.
1. Does Council have questions or feedback on the proposed effluent water temperature solution alternatives?
Engineering Technician II Scott Fleury introduced James Bledsoe, Project Manager for Keller Associates, Dick Pedersen Director of the Oregon Department of Environmental Quality (DEQ), Jon Gasik, Permit Writer and Ranei Nomura also from DEQ and from The Freshwater Trust, Alan Horton, Managing Director and David Primozich, Director of Ecosystem Services, and David Laurence, Board of Directors member.
Mr. Fleury provided background on Keller Associates winning the bid for the Water Master Plan and status of completed items since June 2010. The primary focus was effluent temperature and that the City will not meet new permit requirements. DEQ was expecting a solution from the City September 2011 in order to draft a new permit by the end of the year.
Mr. Bledsoe gave a presentation on options to modify effluent temperatures that included:
Wastewater Treatment Requirements - Regulatory Requirements
· 1992 Bear Creek Total Maximum Daily loads (TMDLs) phosphorus, ammonia, chlorine
· 2007 Bear Creek TMDLs – temperature, bacteria, and sediment
· Oregon Administrative Rule 340045-0053 – address thermal plume or “near field” concerns
· Ashland NPDES Permit
Spawning Season Thermal Limits graph
· Worst condition late October where the limit is 5 and the City is close to 45
· Based on 1 million kilocalories added to Ashland Creek or Bear Creek daily calculated by flow rate and what the temperature of the flow is based on specific criteria
Reuse Options – Full Reuse on Imperatrice Property
· Irrigates 433 + acres
· Large storage volume requires to address should season
· Benefits – Imperatrice property water rights can be transferred, lowers O&M cost, reuse can be phased into community over time with additional piping
· Drawbacks – Water is removed from Ashland/Bear creeks, highest cost option
· NPV - $10.1 M
Mr. Bledsoe and Mr. Gasik clarified during a shoulder period the ground cannot absorb the effluent and that potentially creates groundwater contamination because of nitrates. The cost increase for this estimate versus the one prior was the inclusion of storage and shoulder periods.
Currently, the City of Silverton was running effluent through a series of terraced ponds to decrease temperatures but it was not as successful due to fewer surfaces and the sun.
Partial Reuse to Offset Existing Imperatrice Property Water Right
· Benefits – lower capital cost, water rights can be transferred, some discharge can remain in creeks during critical periods
· Drawbacks – Higher O&M, additional cooling required options required
· NPV = $5.8M - $9.4M
Partial Reuse water was acceptable for agriculture. Without membranes, it would provide Class B effluent and with membranes produced Class A effluent.
Effluent Discharge Options
· Discharge to Talent Irrigation District
o Too many real and perceived obstacles – chemicals, public acceptance, shoulder seasons
o Additional cooling improvements still required
· Blending / Flow Augmentation
o Temperature data gathered shows that this is not a viable option
o Concerns about water quality of water source
· Hyporheic (Shallow Groundwater)
o Previously recommended by Carollo
o Additional investigation of soil data suggests that this will be land intensive, availability of suitable soils is questionable
o Significant additional effort required to determine if feasible
This was not a solution for the Imperatrice property because the soil would not allow the water to drain quickly enough. It would also require the City to own and maintain the entire downstream water path and there could be no wells. Additionally TID water was too warm in August based on samples taken from the Gresham outfall.
· Cooling Town / Chiller
o Cooling tower alone not sufficient – Chiller required
o Pre and post cooling storage required
o Benefits – Compliance can be achieved quickly and with certainty, eliminates “near field” temperature concerns
o Drawbacks – Expensive, high O&M costs, not very “green”
o NPV = $8.6M - $11.6M
A concern was when the flow in a specific section of Ashland Creek was predominantly treated with effluent it could strand fish on the banks when water levels lowered.
· Trading (Shading) – Recommended
o Not considered by Carollo in recent evaluation of options – new DEQ protocols make it more feasible
o Involves planting native trees along 8+ miles of Bear Creek
o Relocate outfall to Bear Creek, small constructed wetlands (modifications to Glendower Pond)
o Benefits – natural approach to achieve compliance, provides other ecological benefits
o Drawbacks – more uncertainty than cooling, potential minor additional local cooling in future
o NPV = $2.7M
The City could provide maintenance of the riparian structure or hire The Freshwater Trust. Mr. Horton and Mr. Primozich explained how The Freshwater Trust would purchase the property, secure easements to plant the trees then care for them for 25 years for an annual fee. The trees would reduce the solar load onto the river and the Trust would use a 2-1 ratio to provide 100-million-kilocalorie instead of the required 50-million-kilocalorie impact.
Mr. Pedersen explained predictive modeling at DEQ in terms of temperature impacts on a watershed scale based on what vegetation could exist in a riparian area and the amount of shade produced translated to thermal load into a stream. Ms. Nomura further explained The Freshwater Trust would conduct site visits to the property to determine shade potential and regular scheduled revisits to monitor success.
Mr. Pedersen noted climate change models were not sophisticated enough at this point. Building a riparian structure in the watershed would allow the City to manage and hold water during times of drought. The Tualatin River has been successful putting in a riparian structure instead of a Chiller. Trading was innovative and new at this point with very few municipalities involved. DEQ was in the process of drafting the permit and determining a compliance schedule for the City. Compliance used a “soon as possible” basis that could extend over several years.
The Freshwater Trust would manage implementation that included the cost details on planting 1600 stems per acre, developing 20-25 year stewardship agreements with each landowner, and working with local non-profit groups on planting and maintenance. The Freshwater Trust would assume the initial risk of securing the landowner, acquiring the trees, and hiring groups to plant the trees to meet DEQ standards. A third party would certify the project met the standards and the City would then start paying for the program annually over 20-25 years.
Council was interested in exploring the Trading option further but had some concerns regarding regulatory certainty. Mr. Gasik clarified the calculations were based on worse case scenarios of the lowest flow conditions over a ten year period and reiterated the project doubled the required 50-million-kilocalorie.
2. Look Ahead Review
City Administrator Martha Bennett reviewed items on the Look Ahead.
Meeting adjourned at 7:15 p.m.
Assistant to the City Recorder