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Cheyenne Canyon Tussock Moth Control Project

Soils and Hydrology Report

May 16, 2016

Jamie Krezelok

PSICC-San Isabel Zone Hydrologist

Purpose and Need The purpose of this project is to minimize the spread and intensity of the Douglas-fir Tussock Moth

outbreak in the Colorado Springs area. The project is needed to complement state and local agency

and landowner efforts to control the moth. The greater Colorado Springs area is mosaic of private,

city, state, and federal lands. The juxtaposition of different landownership, as well as divergent

management objectives among local, state, and federal agencies, requires a high level of

collaboration and communication to control the current outbreak. The Tussock Moth causes

defoliation and kills Douglas-fir and other coniferous trees. These trees are a valued component of

the scenic backdrop for the communities, enhance recreation values, and provide watershed

protection and wildlife habitat.

On National Forest lands, the Tussock Moth outbreak is immediately adjacent to private, municipal,

and state lands; lies within the Wildland Urban Interface; and is occurring within a heavily-used

recreation area. There are concerns that the outbreak may continue to spread on National Forest

lands and onto adjacent private, city, and state lands. The project is intended to minimize additional

Douglas-fir mortality on the Pike National Forest adjacent to current infestations.

The Tussock Moth is a native defoliator with well documented outbreaks occurring in Colorado

since at least the 1930’s. These outbreaks typically last for two to four years. On the Pike National

Forest, the 1993 to 1996 outbreak resulted in 30 to 40 percent Douglas-fir mortality, affecting

18,000 acres. Other outbreaks have been smaller and more isolated. The current outbreak was first

noticed in 2014 on Cheyenne Mountain State Park and Cheyenne Mountain Air Force Station land.

The current Cheyenne Canyon Tussock Moth infestation covers approximately 1,000 acres across

private, city, state, and federal land ownership. In the Cheyenne Canyon area, there are

approximately 50 acres of infestation on National Forest lands. There are mixed stands of

ponderosa pine, Douglas-fir, and white fir adjacent to existing infestations that could potentially be

affected by spread of the Tussock Moth. Within the project area there are old growth Douglas-fir

and Douglas-fir plantations that are now 80 to 110 years old. Treatments within the project area

would maintain desired forest structure by protecting high-value trees, including old growth and

large diameter Douglas-fir adjacent to current infestations, and complement moth control actions on

nearby lands under state, local and private ownership.

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Proposed Action The Pike & San Isabel National Forests and Cimarron & Comanche National Grasslands propose to

implement control measures to minimize the spread and intensity of the Douglas-fir Tussock Moth

outbreak on National Forest System Lands within the Wildland Urban Interface near Colorado

Springs.

The Project Area encompasses 408 acres near Cheyenne Canyon in El Paso County, Colorado. The

affected areas are in portions of T14S, R67W, Sections 28, 29, 32, and 33; and T15S, R67W,

Sections 4, 5, 9, and 10. The attached map below shows the current outbreak and the areas on

National Forest System Land that are proposed for treatment.

In separate actions, treatments are scheduled to occur on private, city, and state lands adjacent to the

National Forest. Those treatments are separate from this proposal and are not part of the Forest

Service proposed action.

Control of the moth would be accomplished using Foray 48B Biological Insecticide. The

insecticide would be applied from the air by helicopter. A single treatment would occur during the

period when treatment would be most effective, which is most likely to happen during the month of

June 2016. No application would occur in areas where surface water is present, including ponds,

lakes, and wetlands and perennial, intermittent, and ephemeral streams. A 100 foot no spray buffer

on either side of all perennial and ephemeral streams will be applied. Best management practices

and all EPA label directions will be strictly followed.

The treatment area would be closed to the public during the period of aerial application.

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Figure 1. Cheyenne Canyon Tussock Moth Control Project Map.

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Extraordinary Circumstances Discussion Resource conditions within the project area that could lead to an extraordinary circumstance include

floodplains, wetlands, and the 1913 and 1924 Congressional Watershed Reserve Lands.

Floodplains and Wetlands—to protect these resources, no application would occur in areas where

surface water is present, including ponds, lakes, and wetlands and perennial, intermittent, and

ephemeral streams. A 100 foot no spray buffer will be applied to either side of all streams.

1913 and 1924 Congressional Watershed Reserve Lands (The Reserve)—The Reserve covers the

northern half of the proposed treatment area. These Acts define the authorities and responsibilities

for the City of Colorado Springs and the Department of Agriculture:

“Now therefore, for the purpose of conserving and protecting the water supply of the said city, the

Secretary of Agriculture agrees:

First. That the use of said lands will not be permitted without the approval of the proper city

authorities, except for the following purposes, to wit: Measures necessary for the proper protection

and care of the forests…”

Second. …to observe any sanitary regulations as may be proposed by the said city…

Third. That, so far as practicable with the means at his disposal, the Secretary of Agriculture will

extend and improve the forests upon these lands…by the most approved methods of silviculture and

forest management.”

As part of the planning process, the Forest Service collaborated with Colorado Springs Utilities

(Utilities) to determine appropriate protections for The Reserve. The record of those

communications is included in Attachment A and is available in the project record. The response to

Utilities comments and refinements made to the initial proposed action based upon those comments

are included in Attachment B.

One design criteria was added in response to a Utilities’ requirement: “in the event that the USFS

does implement a spraying project and that any spraying near open water, relative to perennial or

ephemeral streams, will require a minimum 100 foot buffer for the protection of Utilities’ source

waters in these specified drainages…” Based upon this requirement, a 100 foot no spray buffer on

either side of all perennial and ephemeral streams will be applied. “Perennial and ephemeral” was

the language used in Utilities’ request, but the project will apply the buffer to all

streams…perennial, intermittent, and ephemeral, regardless of whether there is water visible.

Utilities also requested the following: “Acknowledging how buffers will bisect the analysis area

into numerous, but smaller polygons, the USFS should be considering the feasibility of an effective

and accurate application to such small areas near water resources…” Based upon this request, a

portion of the southeast treatment polygon was removed. A smaller southwest treatment polygon

was also removed from the proposed action. The 100 foot buffer and removal of some treatment

areas reduced the proposed treatment area to 408 acres (from 511 acres).

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The proposed insecticide, Btk, is a bacterium that occurs naturally on dead or decaying matter in

soil and has been widely used for treating insect pests. Its effects are very specific to caterpillars

and does not appear to pose any significant threat to human health, birds, animals, or aquatic life

(Richardson 1994, Tayabali and Seligy 2000). No spraying would occur where surface water is

present and a 100 foot no spray buffer would be applied on either side of all streams. There would

be no effect to surface or groundwater quality or quantity associated with the insecticide. The

amount of water used during the treatment would not increase runoff or cause increased erosion.

There would be no impact to floodplains and the water quality of The Reserve would be protected.

The proposed treatment would not affect these resources.

Affected Environment The project area is within the Cheyenne Creek (110200030301) 6

th level watershed. Streams from

this watershed flow into Fountain Creek, which is tributary to the Arkansas River. In the watershed

condition assessment (USDA 2010) this watershed was determined to be in condition class II,

functioning at risk, mainly due to degraded aquatic habitat and the presence of aquatic invasive

species. The soils in the area are generally gravelly to sandy loams derived from Pikes Peak

granite. These soils have rapid runoff potential and a high erosion hazard.

State water quality classified uses in the analysis area include aquatic life cold 1, recreation E, water

supply, and agriculture. These designations require that streams and water bodies be: (1) capable

of sustaining a wide range of coldwater biota including sensitive species, (2) suitable for recreation

on or about water bodies where ingestion of small quantities of water is probable, (3) suitable for

drinking following standard treatment procedures, and (4) suitable for irrigation and livestock

consumption. Minimum state water quality standards have been established by the Colorado

Department of Health and Environment (CDPHE) in accordance with these designated beneficial

uses. There are many streams within the watershed that are listed as not meeting these water quality

standards for E. coli (CDPHE 2016).

As mentioned above, approximately 2,060 acres (13%) of the watershed was designated as a

municipal supply watershed by Congress (The Reserve). There are many reservoirs, ditches, wells,

and springs with decreed water rights within the watershed. None of these are within the proposed

treatment area.

Effects Analysis Water Quality

Up to 408 acres of treatment would occur near North Cheyenne Creek, Buffalo Gulch, and other

unnamed tributaries. The total treatment area is less than 3 percent of the total watershed and

approximately 4 percent of the National Forest System lands within the watershed. Treatment

would be done by air and no soil disturbance would occur. The proposed treatment is very specific

to caterpillars and would not affect surface or groundwater quality. There would be no effect to the

beneficial uses associated with the streams and water rights in the area.

This project is consistent with Forest Plan direction for soil and water resources.

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Statement of Effects There would be no effects to floodplain or wetland resources. Water quality would be protected and

no impacts to the 1913 and 1924 Congressional Watershed Reserve Lands would occur.

Literature Cited (CDPHE) Colorado Department of Public Health and Environment. (2016) [Colorado’s Section

303(d) List of Impaired Waters and Monitoring and Evaluation List], [online]. Available:

https://www.colorado.gov/pacific/sites/default/files/93_2016%2803%29.pdf

Richardson, John S. 1994. Effects of the Bacterial Insecticide Bacillus thuringiensis var. kurstaki

(Btk) on a Stream Benthic Community. Canadian Journal of Fish and Aquatic Science

51:1037-1045.

Tayabali, A.F. and V.L. Seligy. 2000. Human cell exposure assays of Baccillus thuringiensis

commercial insecticides: Production of Bacillus cereus-like cytolytic effects from outgrowth

of spores. Environmental Health Persectives 108:919-930.

(USDA) United States Department of Agriculture, Forest Service. 2010. Watershed Condition

Classification Technical Guide. Primary Authors J. P. Potyondy and T.W. Geier. 70 pp.

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Attachment A. Communication history between Colorado Springs Utilities and the Forest Service,

regarding the Cheyenne Tussock Moth Control Project.

4/13: Email “seeking input from individual members of the EPCRWC (El Paso County Regional

Watershed Collaborative) on the initial proposed action” – Utilities is a member of EPCRWC.

4/13: Initial conversation about the project between Mike Welker, Forest Service Project Team

Leader, and Eric Howell, Utilities, at City of Colorado Springs Public Meeting.

4/20: Conversation (regarding the project proposal) between Howell and Welker at the Forest

Service Public Open House.

4/21: Email from Mike Welker to Eric Howell requesting Utilities’ “input on potential impacts to

the water supply reserve and also any additional protection that we should consider for our final

proposed action.”

4/29: Initial comments received from Utilities.

4/30: Email from Mike Welker to Eric Howell requesting additional clarification on “additional

protections that need to be incorporated into our proposed action to ensure there are no impacts to

the ‘reserve’ and water quality.”

5/4: Amended comments received from Utilities.

5/16: Email from Welker to Howell with new proposed action and response to Utilities’ comments

(Attachment B).

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Attachment B. Contents of email sent to Colorado Springs Utilities on May 16, 2016 – response to

comments and changes made to the initial proposed action.

From: Welker, Michael -FS

Sent: Monday, May 16, 2016 11:41 AM

To: 'Eric Howell' <ehowell@csu.org>

Subject: U.S. Forest Service Cheyenne Canyon Tussock Moth Control Project Proposed Action

Hello Eric: Attached is our proposed action for the Cheyenne Canyon Tussock Moth Control Project. Based

upon Colorado Springs Utilities’ (Utilities) concerns and requirements for the 1913 and 1924 Congressional

Watershed Reserve Lands, the new proposed action will include the following design criteria:

“No application would occur in areas where surface water is present, including ponds, lakes, and wetlands

and perennial, intermittent, and ephemeral streams. A 100 foot no spray buffer on either side of all perennial

and ephemeral streams will be applied.” “Perennial and ephemeral” was the language used in your request,

but for the project we will apply the buffer to all streams…perennial, intermittent, and ephemeral, regardless

of whether there is water visible. The design criteria was added in response to Utilities’ requirement: in the

event that the USFS does implement a spraying project and that any spraying near open water, relative to

perennial or ephemeral streams, will require a minimum 100 foot buffer for the protection of Utilities’

source waters in these specified drainages…”

After modeling the design criteria, we removed a portion of the southeast polygon, because there was little

area left to spray (see map in attached Proposed Action). The smaller southwest polygon was also removed

from the proposed action. The 100 foot buffer and removal of some treatment areas reduced the proposed

treatment area to 408 acres (from 511 acres). The change is directly related and responsive to another

Utilities’ request: “Acknowledging how buffers will bisect the analysis area into numerous, but smaller

polygons, the USFS should be considering the feasibility of an effective and accurate application to such

small areas near water resources…”

Also, recognizing the costs identified by Utilities that is associated with water quality monitoring and water

loss, we are coordinating with the City of Colorado Springs (City) to complete treatments in the North and

South Cheyenne Canyon Drainages at the same time. Utilities’ comment was…“it is very much a necessity

that the USFS and City coordinate the complete spraying of the North and South Cheyenne Canyon

drainages at the same time. Utilities has agreed to turn out its diversions on these creeks during the City’s

project, and will require an process of water quality sampling and verification before these sources can be

turned back into operation. Therefore, it is essential that any spraying by the USFS be coordinated with the

City to avoid duplication of efforts and water loss costs…” We do plan to treat on the same days as the

City’s treatments to limit associated costs.

A decision on implementing the project has not yet been made. We anticipate a decision by our Forest

Supervisor on or before June 1.

Please give me a call if you have any questions. I will be attending the Stakeholder meeting next week

(5/24) at The Broadmoor. This meeting will be the final polygon progression planning, at which we will

work to ensure that our treatments are occurring on the same days as the City’s. Aside from this meeting,

do you see the need for any additional coordination? Please let me know and I will make myself

available for that.

Thank you for the comments and for the guidance needed to protect the 1913 and 1924 Congressional

Watershed Reserve Lands.