Outline The Watershed Association Reservoirs and Watershed The - - PowerPoint PPT Presentation

Colorado Watershed Assembly, October 12th, 2016 Laurie Rink, BMW Chair

 The Watershed Association  Reservoirs and Watershed  The Nexus  The Issues  Watershed Management  Benefits of Collaboration

Outline

• Entities that utilize or have an effect on water quantity and quality in

contributing watershed

• Wastewater agencies, drinking water providers, raw water providers,

cities/counties, regulatory agencies, recreational interests Stakeholders

• Identifying water quality issues
• Developing mutually agreeable, sustainable solutions
• Focus on meeting water quality standards that protect all uses –

irrigation, livestock watering, municipal drinking water, recreation, fisheries/aquatic life Collaboration

• Owned by FRICO (Farmer’s Reservoir and Irrigation

Company)

• Uses – Drinking Water, Irrigation, Recreation, Aquatic Life
• Recreation Lease to Colorado Parks and Wildlife – Barr Lake

State Park

• Filled during the winter and early spring
• Releases during irrigation season (May – Sept)
• Source water S. Platte at Burlington headgate
• 30,071 AF volume
• 1,833 surface acres

Barr Lake

• Owned by FRICO
• Uses – Drinking Water, Irrigation, Recreation, Aquatic
• Filled winter/early spring, releases during irrigation season
• Source water S. Platte at Platte Valley headgate and Beebe

Canal

• 24,029 AF volume
• 2,082 surface acres

Milton Reservoir

• Population of 2.5 million

(1 in 2 Coloradoans)

• 850 sq. miles including 6

Front Range counties

• 90% privately owned
• 35% residential, industrial,

and commercial

• 49% agricultural
• 500 miles of streams
• 550 miles of canals

Watershed

Barr rr Lake Milt lton

• n Res.

s. Cherry rry Cr. Res. es. Bear ar Cr. Res. s. Stand ndley ey Res. es. Chatfi tfield Res. s. Mars rsto ton Lake

Creeks, Streams, and Reservoirs

• S. Platte

e River

Bear Creek Cher erry ry Cree eek Clear r Creek Big Dry Creek Sand Creek 1st

st, 2nd nd, & 3rd Creek

Auror rora Res. s.

• South Platte River watershed forms the source

water for Barr and Milton Reservoirs

• Senior water rights can sweep the river
• Meeting water quality standards in the

reservoirs requires watershed management

Symptoms

Excessive Nutrients

(Phosphorus Nitrogen)

Algae Blooms

Low Oxygen High pH Fish Kills Poor Clarity Taste/Odor Aesthetics

Problem

Barr and Milton are classified as hypereutrophic

Cultural Eutrophication

 2002 State 303(d) listing for pH impairment (both Barr

and Milton) – exceedences above 9.0 pH units

 2010 listing for dissolved oxygen  Require development of a Total Maximum Daily Load

A TMDL is a calculation of the maximum amount of a pollutant that a water body can receive and still meet water quality standards, and an allocation of that amount to the pollutant's sources.

Nonpoint/ Background Loads Margin of Safety Point Source Loads

Total Allowable Load

 pH and DO

O TM TMDL L

• Addresses hypereutrophic conditions
• Based on watershed and in-lake modeling
• Phased based upon number of uncertainties

 Establi

blishe shed d Wate ter r Qu Quality ity Goals ls

• Total phosphorus in-lake 100 µg/L
• Chlorophyll of 25 µg/L
• Alkalinity of 95 mg/L

• External Sources (Watershed)
• Wastewater Point Sources
• Storm Water Point Sources
• Urban Non-Permitted Storm Water
• Agricultural Nonpoint Sources
• Internal Sources
• In-Reservoir Recycled Nutrients

>90% reduction in P needed to meet pH standard

Source of Phosphorus to Barr Lake Current Load (kg/yr) % of Total Current Load Load Reduction Rationale Target Load Reduction (%) Target Load (kg/yr) Target In-Lake Concentration (ug/L) Burlington Pump Works 26,075 37.1% Treatment upgrade: 2,800 ug/L to 100 ug/L 96.5% 913 100 Littleton-Englewood WWTP 33,893 48.2% Treatment upgrade: 2,900 ug/L to 100 ug/L 96.5% 1,186 100 Centennial WWTP 1,194 1.7% Treatment upgrade: 700 ug/L to 100 ug/L 85.5% 173 100 MS4 Regulated Areas 2,189 3.1% Some activity over last decade, plus more BMPs 20.0% 1,751 100 Wasteload Total 63,351 90.0% 93.6% 4,023 100 Upstream background 3,025 4.3% Background load is targeted for a 75% reduction through in-canal treatment 75.0% 756 100 Benthic P Load from Barr 4,000 5.7% In-lake treatment to inactivate P in upper 10 cm of sediment 75.0% 1,000 100 Load Total 7,025 10.0% 75.0% 1,756 100 Total Load (all sources) 70,376 100.0% Calculated loading limit to achieve maximum target load of 5,900 kg/yr and target in- lake maximum concentration of 100 ug/L 91.8% 5,779 100 Wasteloads Loads

 WWTP

TP Point int Sources urces (reduc

duce 58,89 ,890 0 kg/yr yr)

• Regulation 85 for nutrient controls (1.0 mg/L)
• Further reductions addressed in discharge permits

 MS4 Poi

• int

nt Sou

• urc

rces es (reduce

duce 438 38 kg/yr yr)

• Individual and General Permits

 Background

kground (reduce

duce 2,2 ,269 69 kg/yr yr)

• In-canal phosphorus treatment

 Alum

• Been around for 3,000+ years
• Used in U.S. lakes since 1970
• Common Drinking Water Technology
• Not a Herbicide, inactivates P
• Liquid Alum readily available

Inlet Treatment

Amount of P Removed before Barr Lake

• 2,500 kg/yr (upstream background)
• 14,500 kg/yr (background plus PS)
• 53,250 kg/yr (75% reduction of annual load)
• 68,160 kg/yr (96% reduction of annual load)

Technique to Remove P

• Alum (coagulant)

Where the P goes

• Settling pond
• Barr Lake
• Combination

 Off-line channel  Internal & External  Predictable  Reliable (90% removal)  Cost effective  Collaboration  Innovative

 Inter

ternal nal Load ading ing (reduc

duce 3,000 000 kg/yr yr)

• Dredging
• Oxygenation
• Artificial Circulation
• Phosphorus Inactivation (Alum)
• If watershed management continues and a phosphorus

inactivation system is built no action may be needed

• Hybrid Circulation and Inactivation System
• least expensive way to meet water quality goals
• can substitute for more expensive watershed

management techniques

• Biomanipulation



Goal was to reduce bioturbation and internal loading of phosphorus



1,180 – Carp removed



9,800 – Pounds composted



28.2 – Pounds of phosphorus removed

 Comprehensive plan for nutrient control  Outside of normal point source control solutions  Incorporates adaptive management principles  Innovations may prove transferrable to other

Colorado lakes systems

 Selection of most effective solutions that meet

regulatory requirements and consider both cost and the environment